Merge branch 'worktree-agent-a549a3d1a8812e372'

# Conflicts:
#	apps/effectcraft-cli/src/main.rs
#	crates/host/src/lib.rs
#	crates/render/src/lib.rs

apps/effectcraft/src/main.rs

@@ -54,10 +54,10 @@ fn main() -> eframe::Result {
                 let _ = session.execute("file.openDemoProject", json!({}));
             }
             let media: Vec<String> = files.iter().filter(|f| !f.ends_with(".ecproj")).cloned().collect();
-            if !media.is_empty() {
-                if let Err(e) = session.execute("file.import", json!({"paths": media})) {
-                    eprintln!("effectcraft: {e}");
-                }
+            if !media.is_empty()
+                && let Err(e) = session.execute("file.import", json!({"paths": media}))
+            {
+                eprintln!("effectcraft: {e}");
             }
             let mut app = EffectcraftApp::new(session);
             app.ui.start_screen = home;

crates/engine/src/commands/anim.rs

@@ -0,0 +1,414 @@
+//! Keyframe clipboard, selection, nudging, direct key/ease edits (Graph Editor handles) and key
+//! inspection for the Keyframe Velocity / Keyframe Interpolation dialogs.
+
+use effectcraft_keyframe::{Ease, Interp, Keyframe, key_at, retime_roving, side_ease};
+use effectcraft_project::{LayerId, Property, Uid};
+use effectcraft_time::Tick;
+use serde_json::{Value, json};
+
+use super::prop::{edit_keys, prop_ref};
+use super::{CommandSpec, bad, comp_id, f_p, has_comp, has_keys, layers_p, merge_p, str_p, time_p};
+use crate::{EngineError, KeyClip, KeyRef, Result, Session, cmd, query};
+
+fn has_key_clip(s: &Session) -> std::result::Result<(), String> {
+    has_comp(s)?;
+    if s.state.key_clipboard.is_empty() { Err("no keyframes have been copied".into()) } else { Ok(()) }
+}
+
+/// Copy the selected keyframes (Edit ▸ Copy with keys selected).
+fn copy(s: &mut Session, _: &Value) -> Result<Value> {
+    let comp = s.active_comp().ok_or(EngineError::NoComp)?;
+    let mut groups: std::collections::BTreeMap<(LayerId, Uid), Vec<Tick>> = Default::default();
+    for k in &s.state.selected_keys {
+        groups.entry((k.layer, k.prop)).or_default().push(k.time);
+    }
+    // Earliest selected key in comp time: pasted keys keep their offsets from it.
+    let mut earliest: Option<Tick> = None;
+    for ((lid, _), times) in &groups {
+        if let Some(l) = comp.layer(*lid) {
+            for t in times {
+                let ct = l.comp_time(*t);
+                earliest = Some(earliest.map_or(ct, |e: Tick| e.min(ct)));
+            }
+        }
+    }
+    let earliest = earliest.ok_or_else(|| bad("keys.copy", "select keyframes first"))?;
+    let mut clip = vec![];
+    for ((lid, uid), times) in groups {
+        let Some(l) = comp.layer(lid) else { continue };
+        let Some(pr) = l.props.find(uid) else { continue };
+        let Some(path) = l.props.match_path_of(uid) else { continue };
+        let mut keys: Vec<Keyframe> = pr.keys.iter().filter(|k| times.contains(&k.time)).cloned().collect();
+        for k in &mut keys {
+            k.time = l.comp_time(k.time) - earliest;
+        }
+        clip.push(KeyClip { layer: lid, path, keys });
+    }
+    let n: usize = clip.iter().map(|c| c.keys.len()).sum();
+    s.state.key_clipboard = clip;
+    s.state.clip_is_keys = true;
+    Ok(json!(n))
+}
+
+/// Values of the same kind (and dimensionality) can receive each other's keys.
+fn compatible(a: &Property, b: &effectcraft_keyframe::Value) -> bool {
+    a.value.kind_name() == b.kind_name() && a.value.components().len() == b.components().len()
+}
+
+/// Paste copied keyframes at the current time into the target layers' properties.
+fn paste(s: &mut Session, p: &Value) -> Result<Value> {
+    let clip = s.state.key_clipboard.clone();
+    if clip.is_empty() {
+        return Err(bad("keys.paste", "no keyframes have been copied"));
+    }
+    let cid = comp_id(s, p)?;
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let t = time_p(s, p, Some(comp));
+    let (_, mut targets) = layers_p(s, p)?;
+    if targets.is_empty() {
+        targets = clip.iter().map(|c| c.layer).collect();
+        targets.dedup();
+    }
+    let explicit = p.get("prop").and_then(Value::as_u64).or_else(|| {
+        let path = str_p(p, "path")?;
+        comp.layer(*targets.first()?)?.props.prop(path).map(|pr| pr.uid)
+    });
+    // (layer, prop uid, clip index)
+    let mut plan: Vec<(LayerId, Uid, usize)> = vec![];
+    for lid in &targets {
+        let Some(l) = comp.layer(*lid) else { continue };
+        for (ci, c) in clip.iter().enumerate() {
+            let Some(sample) = c.keys.first().map(|k| &k.value) else { continue };
+            let target = if clip.len() == 1 {
+                explicit
+                    .and_then(|u| l.props.find(u))
+                    .or_else(|| {
+                        s.state.selected_props.iter().filter(|(sl, _)| sl == lid).filter_map(|(_, u)| l.props.find(*u)).find(|pr| compatible(pr, sample))
+                    })
+                    .or_else(|| l.props.prop(&c.path))
+            } else {
+                l.props.prop(&c.path)
+            };
+            if let Some(pr) = target.filter(|pr| compatible(pr, sample) && !pr.static_only) {
+                plan.push((*lid, pr.uid, ci));
+            }
+        }
+    }
+    if plan.is_empty() {
+        return Err(bad("keys.paste", "no compatible property to paste into (select a property of the same type)"));
+    }
+    s.edit("Paste Keyframes", None, |proj, st| {
+        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        let mut sel = vec![];
+        for (lid, uid, ci) in &plan {
+            let Some(l) = comp.layer_mut(*lid) else { continue };
+            let times: Vec<Tick> = clip[*ci].keys.iter().map(|k| l.layer_time(t + k.time)).collect();
+            let Some(pr) = l.props.find_mut(*uid) else { continue };
+            for (k, lt) in clip[*ci].keys.iter().zip(times) {
+                let mut k = k.clone();
+                k.time = lt;
+                if let Some(v) = pr.value.coerce_json(&k.value.to_json()) {
+                    k.value = v;
+                }
+                if pr.hold_only {
+                    k = k.hold();
+                }
+                match pr.keys.binary_search_by(|x| x.time.cmp(&k.time)) {
+                    Ok(i) => pr.keys[i] = k,
+                    Err(i) => pr.keys.insert(i, k),
+                }
+                sel.push(KeyRef { layer: *lid, prop: *uid, time: lt });
+            }
+            retime_roving(&mut pr.keys, pr.spatial);
+        }
+        st.selected_keys = sel;
+        Ok(json!(st.selected_keys.len()))
+    })
+}
+
+/// Select every keyframe of the selected properties, or of the given / selected layers.
+fn select_all(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, mut layers) = layers_p(s, p)?;
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let mut sel = vec![];
+    if p.get("layers").is_none() && p.get("layer").is_none() && !s.state.selected_props.is_empty() {
+        for (lid, uid) in &s.state.selected_props {
+            if let Some(pr) = comp.layer(*lid).and_then(|l| l.props.find(*uid)) {
+                sel.extend(pr.keys.iter().map(|k| KeyRef { layer: *lid, prop: *uid, time: k.time }));
+            }
+        }
+    } else {
+        if layers.is_empty() {
+            layers = comp.layers.iter().map(|l| l.id).collect();
+        }
+        for l in comp.layers.iter().filter(|l| layers.contains(&l.id)) {
+            l.props.walk("", &mut |_, pr| sel.extend(pr.keys.iter().map(|k| KeyRef { layer: l.id, prop: pr.uid, time: k.time })));
+        }
+    }
+    s.state.selected_keys = sel;
+    Ok(json!(s.state.selected_keys.len()))
+}
+
+/// Move the selected keys by whole frames (Alt+→ / Alt+←, Shift for 10 frames).
+fn nudge(s: &mut Session, p: &Value) -> Result<Value> {
+    let frames = p.get("frames").and_then(Value::as_i64).ok_or_else(|| bad("keys.nudge", "missing `frames`"))?;
+    let comp = s.active_comp().ok_or(EngineError::NoComp)?;
+    let d = Tick(comp.frame_duration().0 * frames);
+    edit_keys(s, "Nudge Keyframes", merge_p(p), move |_, _, t| {
+        *t += d;
+        true
+    })
+}
+
+/// Edit one key directly: move it in time and/or set its value (Graph Editor drags).
+fn set_key(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, lid, uid) = prop_ref(s, p, "keys.set")?;
+    let t = Tick::from_seconds_f64(f_p(p, "time").ok_or_else(|| bad("keys.set", "missing `time` (layer time of the key)"))?);
+    let new_t = f_p(p, "newTime").map(Tick::from_seconds_f64);
+    let value = p.get("value").cloned();
+    let fr = s.project.comp(cid).map(|c| c.frame_rate);
+    s.edit("Edit Keyframe", merge_p(p), |proj, st| {
+        let l = super::layer_mut(proj, cid, lid)?;
+        let pr = l.props.find_mut(uid).ok_or_else(|| bad("keys.set", "no property"))?;
+        let i = nearest_key(&pr.keys, t).ok_or_else(|| bad("keys.set", "the property has no keyframes"))?;
+        let old_t = pr.keys[i].time;
+        if let Some(v) = &value {
+            let nv = pr.keys[i].value.coerce_json(v).ok_or_else(|| bad("keys.set", format!("can't use {v} here")))?;
+            pr.keys[i].value = nv;
+        }
+        let mut nt = old_t;
+        if let Some(n) = new_t {
+            nt = fr.map(|r| r.snap_nearest(n)).unwrap_or(n);
+            // Keys can't pass their neighbours or share a time.
+            let lo = if i > 0 { pr.keys[i - 1].time.0 + 1 } else { i64::MIN };
+            let hi = if i + 1 < pr.keys.len() { pr.keys[i + 1].time.0 - 1 } else { i64::MAX };
+            nt = Tick(nt.0.clamp(lo, hi));
+            pr.keys[i].time = nt;
+        }
+        retime_roving(&mut pr.keys, pr.spatial);
+        let nt = pr.keys.get(i).map(|k| k.time).unwrap_or(nt);
+        for k in st.selected_keys.iter_mut().filter(|k| k.layer == lid && k.prop == uid && k.time == old_t) {
+            k.time = nt;
+        }
+        Ok(json!({"time": nt.seconds()}))
+    })
+}
+
+fn nearest_key(keys: &[Keyframe], t: Tick) -> Option<usize> {
+    if let Some(i) = key_at(keys, t) {
+        return Some(i);
+    }
+    keys.iter().enumerate().min_by_key(|(_, k)| (k.time.0 - t.0).abs()).map(|(i, _)| i)
+}
+
+/// Set one side's temporal ease of a key (Graph Editor handle drags, scripting).
+fn set_ease(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, lid, uid) = prop_ref(s, p, "keys.setEase")?;
+    let t = Tick::from_seconds_f64(f_p(p, "time").ok_or_else(|| bad("keys.setEase", "missing `time`"))?);
+    let out = match str_p(p, "side") {
+        Some("in") => false,
+        Some("out") => true,
+        _ => return Err(bad("keys.setEase", "`side` must be in or out")),
+    };
+    let dim = p.get("dim").and_then(Value::as_u64).map(|d| d as usize);
+    let speed = f_p(p, "speed");
+    let influence = f_p(p, "influence").map(|v| (v / 100.0).clamp(0.001, 1.0));
+    s.edit("Keyframe Velocity", merge_p(p), |proj, _| {
+        let l = super::layer_mut(proj, cid, lid)?;
+        let pr = l.props.find_mut(uid).ok_or_else(|| bad("keys.setEase", "no property"))?;
+        let i = nearest_key(&pr.keys, t).ok_or_else(|| bad("keys.setEase", "no keyframes"))?;
+        let spatial = pr.spatial;
+        let n = if spatial && matches!(pr.keys[i].value, effectcraft_keyframe::Value::Vec2(_) | effectcraft_keyframe::Value::Vec3(_)) {
+            1
+        } else {
+            pr.keys[i].value.dims().max(1)
+        };
+        // Start from what the side presents now so untouched dimensions keep their shape.
+        let cur: Vec<Ease> = (0..n).map(|d| side_ease(&pr.keys, i, d, spatial, out).unwrap_or_default()).collect();
+        let k = &mut pr.keys[i];
+        let list = if out { &mut k.out_ease } else { &mut k.in_ease };
+        if list.len() != n {
+            *list = cur.clone();
+        }
+        for (d, e) in list.iter_mut().enumerate() {
+            if dim.is_some_and(|x| x != d) && n > 1 {
+                continue;
+            }
+            if let Some(v) = speed {
+                e.speed = v;
+            }
+            if let Some(v) = influence {
+                e.influence = v;
+            }
+        }
+        if out {
+            k.out_interp = Interp::Bezier;
+        } else {
+            k.in_interp = Interp::Bezier;
+        }
+        k.auto_bezier = false;
+        // Continuous Bezier keys keep matching speeds on both sides.
+        if k.continuous {
+            let src = if out { k.out_ease.clone() } else { k.in_ease.clone() };
+            let other = if out { &mut k.in_ease } else { &mut k.out_ease };
+            if other.len() != src.len() {
+                *other = src.clone();
+            }
+            for (o, sv) in other.iter_mut().zip(&src) {
+                o.speed = sv.speed;
+            }
+            k.in_interp = Interp::Bezier;
+            k.out_interp = Interp::Bezier;
+        }
+        Ok(Value::Null)
+    })
+}
+
+/// Speed units for a property (Keyframe Velocity dialog).
+fn units(pr: &Property) -> &'static str {
+    use effectcraft_project::ParamUi;
+    if pr.spatial {
+        return "pixels/sec";
+    }
+    match pr.ui {
+        ParamUi::Angle => "degrees/sec",
+        ParamUi::Percent => "%/sec",
+        ParamUi::Slider { .. } if pr.match_id == "opacity" => "%/sec",
+        _ if pr.match_id == "opacity" => "%/sec",
+        ParamUi::Pixels => "pixels/sec",
+        _ => "units/sec",
+    }
+}
+
+fn interp_name(i: Interp) -> &'static str {
+    match i {
+        Interp::Linear => "linear",
+        Interp::Bezier => "bezier",
+        Interp::Hold => "hold",
+    }
+}
+
+/// Describe the selected (or given) keys: interpolation, eases per side and dimension, units.
+fn info(s: &mut Session, p: &Value) -> Result<Value> {
+    let comp = s.active_comp().ok_or(EngineError::NoComp)?;
+    let refs: Vec<KeyRef> = match p.get("keys") {
+        Some(Value::Array(a)) => a
+            .iter()
+            .filter_map(|k| {
+                let l = super::resolve_layer(comp, k.get("layer")?)?;
+                Some(KeyRef { layer: l, prop: k.get("prop")?.as_u64()?, time: Tick::from_seconds_f64(k.get("time")?.as_f64()?) })
+            })
+            .collect(),
+        _ => s.state.selected_keys.clone(),
+    };
+    let mut out = vec![];
+    for r in refs {
+        let Some(l) = comp.layer(r.layer) else { continue };
+        let Some(pr) = l.props.find(r.prop) else { continue };
+        let Some(i) = nearest_key(&pr.keys, r.time) else { continue };
+        let k = &pr.keys[i];
+        let spatial = pr.spatial && matches!(k.value, effectcraft_keyframe::Value::Vec2(_) | effectcraft_keyframe::Value::Vec3(_));
+        let dims = if spatial { 1 } else { k.value.dims().max(1).min(if pr.shown_dims > 0 && !l.is_3d() { pr.shown_dims as usize } else { 4 }) };
+        let side = |out: bool| -> Value {
+            json!(
+                (0..dims)
+                    .map(|d| side_ease(&pr.keys, i, d, pr.spatial, out)
+                        .map(|e| json!({"speed": e.speed, "influence": e.influence * 100.0}))
+                        .unwrap_or(Value::Null))
+                    .collect::<Vec<_>>()
+            )
+        };
+        let temporal = if k.auto_bezier {
+            "autoBezier"
+        } else if k.continuous {
+            "continuousBezier"
+        } else if k.in_interp == k.out_interp {
+            interp_name(k.in_interp)
+        } else {
+            "mixed"
+        };
+        let spatial_kind = if !spatial {
+            Value::Null
+        } else if k.spatial_auto {
+            json!("autoBezier")
+        } else if k.spatial_continuous {
+            json!("continuousBezier")
+        } else if k.spatial_in == [0.0; 3] && k.spatial_out == [0.0; 3] {
+            json!("linear")
+        } else {
+            json!("bezier")
+        };
+        out.push(json!({
+            "layer": l.id.0, "prop": pr.uid, "name": pr.name, "path": l.props.match_path_of(pr.uid),
+            "time": k.time.seconds(), "compTime": l.comp_time(k.time).seconds(), "value": k.value.to_json(),
+            "in": interp_name(k.in_interp), "out": interp_name(k.out_interp), "temporal": temporal,
+            "autoBezier": k.auto_bezier, "continuous": k.continuous, "roving": k.roving, "spatial": spatial_kind,
+            "dims": dims, "units": units(pr), "inEase": side(false), "outEase": side(true),
+        }));
+    }
+    Ok(json!(out))
+}
+
+/// Keyframe Assistant ▸ Time-Reverse Keyframes: mirror the selected keys of each property.
+fn time_reverse(s: &mut Session, _: &Value) -> Result<Value> {
+    let cid = s.active_comp_id().ok_or(EngineError::NoComp)?;
+    let sel = s.state.selected_keys.clone();
+    s.edit("Time-Reverse Keyframes", None, |proj, st| {
+        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        let mut groups: std::collections::BTreeMap<(LayerId, Uid), Vec<Tick>> = Default::default();
+        for k in &sel {
+            groups.entry((k.layer, k.prop)).or_default().push(k.time);
+        }
+        let mut new_sel = vec![];
+        for ((lid, uid), times) in groups {
+            let Some(pr) = comp.layer_mut(lid).and_then(|l| l.props.find_mut(uid)) else { continue };
+            let (mut picked, rest): (Vec<Keyframe>, Vec<Keyframe>) = pr.keys.drain(..).partition(|k| times.contains(&k.time));
+            effectcraft_keyframe::time_reverse(&mut picked);
+            new_sel.extend(picked.iter().map(|k| KeyRef { layer: lid, prop: uid, time: k.time }));
+            pr.keys = rest;
+            for k in picked {
+                match pr.keys.binary_search_by(|x| x.time.cmp(&k.time)) {
+                    Ok(i) => pr.keys[i] = k,
+                    Err(i) => pr.keys.insert(i, k),
+                }
+            }
+        }
+        st.selected_keys = new_sel;
+        Ok(json!(st.selected_keys.len()))
+    })
+}
+
+fn keys_or_layers(s: &Session) -> std::result::Result<(), String> {
+    has_comp(s)
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        cmd!("keys.copy", "Copy Keyframes", [], None, "{}", has_keys, copy),
+        cmd!("keys.paste", "Paste Keyframes", [], None, "{layers?, prop?|path?, time?}", has_key_clip, paste),
+        cmd!("keys.selectAll", "Select All Keyframes", ["Edit"], Some("Cmd+Alt+A"), "{layers?}", keys_or_layers, select_all),
+        cmd!("keys.nudge", "Nudge Keyframes", [], None, "{frames, merge?}", has_keys, nudge),
+        cmd!("keys.nudgeForward", "Move Keyframes 1 Frame Later", [], Some("Alt+ArrowRight"), "{}", has_keys, |s, _| nudge(s, &json!({"frames": 1}))),
+        cmd!("keys.nudgeBackward", "Move Keyframes 1 Frame Earlier", [], Some("Alt+ArrowLeft"), "{}", has_keys, |s, _| nudge(s, &json!({"frames": -1}))),
+        cmd!("keys.nudgeForward10", "Move Keyframes 10 Frames Later", [], Some("Alt+Shift+ArrowRight"), "{}", has_keys, |s, _| nudge(
+            s,
+            &json!({"frames": 10})
+        )),
+        cmd!("keys.nudgeBackward10", "Move Keyframes 10 Frames Earlier", [], Some("Alt+Shift+ArrowLeft"), "{}", has_keys, |s, _| nudge(
+            s,
+            &json!({"frames": -10})
+        )),
+        cmd!("keys.set", "Edit Keyframe", [], None, "{layer?, path|prop, time (layer s), newTime?, value?, merge?}", has_comp, set_key),
+        cmd!(
+            "keys.setEase",
+            "Set Keyframe Ease",
+            [],
+            None,
+            "{layer?, path|prop, time (layer s), side: in|out, dim?, speed?, influence? %, merge?}",
+            has_comp,
+            set_ease
+        ),
+        cmd!("keys.timeReverse", "Time-Reverse Keyframes", ["Animation", "Keyframe Assistant"], None, "{}", has_keys, time_reverse),
+        query!("keys.info", "Keyframe Info", "{keys?: [{layer, prop, time}]}", info),
+    ]
+}

crates/engine/src/commands/comp.rs

@@ -62,7 +62,8 @@ fn apply_settings(c: &mut Comp, p: &Value) {
     }
     if let Some(d) = f_p(p, "duration") {
         let old = c.duration;
-        c.duration = Tick::from_seconds_f64(d.max(c.frame_rate.frame_duration().seconds()));
+        // Whole frames, at least one.
+        c.duration = c.frame_rate.snap_nearest(Tick::from_seconds_f64(d)).max(c.frame_rate.frame_duration());
         if c.work_area.1 == old {
             c.work_area.1 = c.duration;
         }
@@ -91,7 +92,7 @@ fn apply_settings(c: &mut Comp, p: &Value) {
 fn new_comp(s: &mut Session, p: &Value) -> Result<Value> {
     let name = str_p(p, "name").unwrap_or("Comp 1").to_string();
     let rate = rate_p(p).unwrap_or(FrameRate::FPS_29_97);
-    let mut c = Comp::new(1920, 1080, rate, Tick::from_seconds_f64(10.0));
+    let mut c = Comp::new(1920, 1080, rate, rate.snap_nearest(Tick::from_seconds_f64(10.0)));
     apply_settings(&mut c, p);
     let id = s.edit("New Composition", None, |proj, st| {
         let mut name = name.clone();

crates/engine/src/commands/edit.rs

@@ -15,7 +15,7 @@ fn can_redo(s: &Session) -> std::result::Result<(), String> {
 }
 fn has_clip(s: &Session) -> std::result::Result<(), String> {
     has_comp(s)?;
-    if s.state.clipboard.is_empty() { Err("the clipboard is empty".into()) } else { Ok(()) }
+    if s.state.clipboard.is_empty() && s.state.key_clipboard.is_empty() { Err("the clipboard is empty".into()) } else { Ok(()) }
 }
 
 fn undo(s: &mut Session, _: &Value) -> Result<Value> {
@@ -39,6 +39,7 @@ fn deselect_all(s: &mut Session, _: &Value) -> Result<Value> {
     s.state.selected_layers.clear();
     s.state.selected_props.clear();
     s.state.selected_keys.clear();
+    s.state.selected_vertices.clear();
     Ok(Value::Null)
 }
 
@@ -72,10 +73,13 @@ fn duplicate(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn delete(s: &mut Session, p: &Value) -> Result<Value> {
-    // Keyframes selected → delete keys; else layers.
+    // Keyframes selected → delete keys; mask vertices → delete them; else layers.
     if !s.state.selected_keys.is_empty() && p.get("layers").is_none() {
         return s.execute("keys.delete", json!({}));
     }
+    if !s.state.selected_vertices.is_empty() && p.get("layers").is_none() {
+        return s.execute("mask.deleteVertices", json!({}));
+    }
     let (cid, ids) = layers_p(s, p)?;
     s.edit("Clear", None, |proj, st| {
         let comp = proj.comp_mut(cid).ok_or(crate::EngineError::NoComp)?;
@@ -97,18 +101,30 @@ fn delete(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 fn copy(s: &mut Session, p: &Value) -> Result<Value> {
+    // Keyframes selected → copy keys (pasted at the CTI).
+    if !s.state.selected_keys.is_empty() && p.get("layers").is_none() {
+        return s.execute("keys.copy", json!({}));
+    }
     let (cid, ids) = layers_p(s, p)?;
+    s.state.clip_is_keys = false;
     let comp = s.project.comp(cid).ok_or(crate::EngineError::NoComp)?;
     s.state.clipboard = comp.layers.iter().filter(|l| ids.contains(&l.id)).cloned().collect();
     Ok(json!(s.state.clipboard.len()))
 }
 
 fn cut(s: &mut Session, p: &Value) -> Result<Value> {
+    if !s.state.selected_keys.is_empty() && p.get("layers").is_none() {
+        s.execute("keys.copy", json!({}))?;
+        return s.execute("keys.delete", json!({}));
+    }
     copy(s, p)?;
     delete(s, p)
 }
 
 fn paste(s: &mut Session, p: &Value) -> Result<Value> {
+    if s.state.clip_is_keys && !s.state.key_clipboard.is_empty() {
+        return s.execute("keys.paste", p.clone());
+    }
     let cid = super::comp_id(s, p)?;
     let clip = s.state.clipboard.clone();
     let new = s.edit("Paste", None, |proj, st| {
@@ -191,10 +207,10 @@ pub fn specs() -> Vec<CommandSpec> {
     vec![
         cmd!("edit.undo", "Undo", ["Edit"], Some("Cmd+Z"), "{}", can_undo, undo),
         cmd!("edit.redo", "Redo", ["Edit"], Some("Cmd+Shift+Z"), "{}", can_redo, redo),
-        cmd!("edit.cut", "Cut", ["Edit"], Some("Cmd+X"), "{layers?}", has_layers, cut),
-        cmd!("edit.copy", "Copy", ["Edit"], Some("Cmd+C"), "{layers?}", has_layers, copy),
+        cmd!("edit.cut", "Cut", ["Edit"], Some("Cmd+X"), "{layers?} (keyframes when keys are selected)", layers_or_keys, cut),
+        cmd!("edit.copy", "Copy", ["Edit"], Some("Cmd+C"), "{layers?} (keyframes when keys are selected)", layers_or_keys, copy),
         cmd!("edit.paste", "Paste", ["Edit"], Some("Cmd+V"), "{}", has_clip, paste),
-        cmd!("edit.clear", "Clear", ["Edit"], Some("Delete"), "{layers?}", has_layers, delete),
+        cmd!("edit.clear", "Clear", ["Edit"], Some("Delete"), "{layers?}", layers_or_keys, delete),
         cmd!("edit.duplicate", "Duplicate", ["Edit"], Some("Cmd+D"), "{layers?}", has_layers, duplicate),
         cmd!("edit.splitLayer", "Split Layer", ["Edit"], Some("Cmd+Shift+D"), "{layers?}", has_layers, split),
         cmd!("edit.selectAll", "Select All", ["Edit"], Some("Cmd+A"), "{}", has_comp, select_all),
@@ -204,6 +220,10 @@ pub fn specs() -> Vec<CommandSpec> {
     ]
 }
 
+fn layers_or_keys(s: &Session) -> std::result::Result<(), String> {
+    if !s.state.selected_keys.is_empty() || !s.state.selected_vertices.is_empty() { super::has_comp(s) } else { has_layers(s) }
+}
+
 fn always_ok(_: &Session) -> std::result::Result<(), String> {
     Ok(())
 }

crates/engine/src/commands/layer.rs

@@ -263,12 +263,13 @@ fn add_item(s: &mut Session, p: &Value) -> Result<Value> {
         ItemKind::Solid(so) => (LayerSource::Solid { item }, (so.width, so.height), None),
         ItemKind::Folder => return Err(bad("layer.addItem", "folders can't be layers")),
     };
-    let start = f_p(p, "time").map(Tick::from_seconds_f64).unwrap_or(Tick::ZERO);
+    let fr = comp.frame_rate;
+    let start = fr.snap_nearest(f_p(p, "time").map(Tick::from_seconds_f64).unwrap_or(Tick::ZERO));
     let id = s.edit("Add Footage to Comp", None, |proj, st| {
         let mut l = build::layer(proj, &comp, &it.name, src, size, dur);
         l.start_time = start;
         l.in_point = start;
-        l.out_point = (start + dur.unwrap_or(comp.duration)).min(comp.duration);
+        l.out_point = fr.snap_nearest((start + dur.unwrap_or(comp.duration)).min(comp.duration)).max(start + fr.frame_duration());
         insert_layer(proj, st, cid, l)
     })?;
     Ok(json!({"layer": id.0}))
@@ -302,6 +303,8 @@ fn select(s: &mut Session, p: &Value) -> Result<Value> {
         s.state.selected_layers = ids;
         s.state.selected_props.clear();
         s.state.selected_keys.clear();
+        let keep = s.state.selected_layers.clone();
+        s.state.selected_vertices.retain(|v| keep.contains(&v.layer));
     }
     Ok(json!(s.state.selected_layers.iter().map(|l| l.0).collect::<Vec<_>>()))
 }
@@ -484,10 +487,62 @@ fn set_parent(s: &mut Session, p: &Value) -> Result<Value> {
             cur = comp.layer(c).and_then(|l| l.parent);
         }
     }
+    // Like AE's pick-whip, parenting keeps the layer where it is: its transform is re-expressed
+    // in the new parent's space (Position, Rotation, Scale), unless `compensate: false`.
+    let compensate = b_p(p, "compensate").unwrap_or(true);
+    let ectx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: s.time(), expr: s.expr.as_deref() };
+    let space = |id: Option<LayerId>| -> effectcraft_geom::Mat3 {
+        id.and_then(|i| comp.layer(i)).filter(|l| !l.is_3d()).map(|l| ectx.layer_to_comp(l).0).unwrap_or(effectcraft_geom::Mat3::IDENTITY)
+    };
+    let decompose = |m: &effectcraft_geom::Mat3| {
+        let a = m.0;
+        let sx = (a[0][0] * a[0][0] + a[1][0] * a[1][0]).sqrt();
+        let det = a[0][0] * a[1][1] - a[0][1] * a[1][0];
+        (a[1][0].atan2(a[0][0]).to_degrees(), sx, if sx > 1e-12 { det / sx } else { 0.0 })
+    };
+    // Per layer: (id, position transform, rotation delta, scale factors).
+    let mut fixes: Vec<(LayerId, effectcraft_geom::Mat3, f64, [f64; 2])> = vec![];
+    if compensate {
+        let new_m = space(parent);
+        for l in comp.layers.iter().filter(|l| ids.contains(&l.id) && !l.is_3d() && l.parent != parent) {
+            let old_m = space(l.parent);
+            let Some(inv) = new_m.inverse() else { continue };
+            let (ro, sxo, syo) = decompose(&old_m);
+            let (rn, sxn, syn) = decompose(&new_m);
+            let k = [if sxn.abs() > 1e-12 { sxo / sxn } else { 1.0 }, if syn.abs() > 1e-12 { syo / syn } else { 1.0 }];
+            fixes.push((l.id, inv * old_m, ro - rn, k));
+        }
+    }
     s.edit("Parent", None, |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
             l.parent = parent;
+            let Some((_, m, dr, k)) = fixes.iter().find(|f| f.0 == l.id) else { continue };
+            let Some(tr) = l.props.sub_mut("transform") else { continue };
+            let map = |pr: &mut effectcraft_project::Property, f: &dyn Fn(&KV) -> KV| {
+                pr.value = f(&pr.value);
+                for key in &mut pr.keys {
+                    key.value = f(&key.value);
+                }
+            };
+            if tr.get("positionX").is_none()
+                && let Some(pr) = tr.get_mut("position")
+            {
+                map(pr, &|v| {
+                    let c = v.as_vec3();
+                    let q = m.apply(effectcraft_geom::vec2(c[0], c[1]));
+                    KV::Vec3([q.x, q.y, c[2]])
+                });
+            }
+            if let Some(pr) = tr.get_mut("rotation") {
+                map(pr, &|v| KV::Scalar(v.as_f64() + dr));
+            }
+            if let Some(pr) = tr.get_mut("scale") {
+                map(pr, &|v| {
+                    let c = v.as_vec3();
+                    KV::Vec3([c[0] * k[0], c[1] * k[1], c[2]])
+                });
+            }
         }
         Ok(())
     })?;
@@ -498,10 +553,10 @@ fn timing(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, ids) = layers_p(s, p)?;
     let t = s.time();
     let op = str_p(p, "op").unwrap_or("set").to_string();
-    let delta = f_p(p, "delta").map(Tick::from_seconds_f64);
-    let start = f_p(p, "start").map(Tick::from_seconds_f64);
-    let inp = f_p(p, "in").map(Tick::from_seconds_f64);
-    let outp = f_p(p, "out").map(Tick::from_seconds_f64);
+    // Layer times stay on frame boundaries of the comp (as in AE).
+    let fr = s.project.comp(cid).ok_or(EngineError::NoComp)?.frame_rate;
+    let snap = |k: &str| f_p(p, k).map(|v| fr.snap_nearest(Tick::from_seconds_f64(v)));
+    let (delta, start, inp, outp) = (snap("delta"), snap("start"), snap("in"), snap("out"));
     s.edit("Layer Timing", merge_p(p), |proj, _| {
         let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
         let fd = comp.frame_duration();
@@ -818,34 +873,6 @@ fn transform_op(s: &mut Session, p: &Value) -> Result<Value> {
     Ok(Value::Null)
 }
 
-fn time_stretch(s: &mut Session, p: &Value) -> Result<Value> {
-    let (cid, ids) = layers_p(s, p)?;
-    let reverse = str_p(p, "op") == Some("reverse");
-    let pct = f_p(p, "percent");
-    s.edit(if reverse { "Time-Reverse Layer" } else { "Time Stretch" }, None, |proj, _| {
-        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
-        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
-            let old = l.stretch;
-            let new = if reverse { -old } else { pct.unwrap_or(old) };
-            if new.abs() < 1.0 {
-                continue;
-            }
-            // Keep the in point fixed: the layer's source span scales around it.
-            let lin = l.layer_time(l.in_point);
-            let lout = l.layer_time(l.out_point);
-            l.stretch = new;
-            if reverse {
-                l.start_time = l.in_point + Tick((lout.0 as f64 * new.abs() / 100.0) as i64);
-            } else {
-                l.start_time = l.in_point - Tick((lin.0 as f64 * new / 100.0) as i64);
-                l.out_point = l.comp_time(lout);
-            }
-        }
-        Ok(())
-    })?;
-    Ok(Value::Null)
-}
-
 fn layer_settings(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, lid) = layer_p(s, p, "layer.settings")?;
     let color = color_p(p, "color");
@@ -977,7 +1004,6 @@ pub fn specs() -> Vec<CommandSpec> {
             has_layers,
             transform_op
         ),
-        cmd!("layer.timeStretch", "Time Stretch…", ["Layer", "Time"], None, "{layers?, percent?, op?: reverse}", has_layers, time_stretch),
     ]
 }
 

crates/engine/src/commands/layer_time.rs

@@ -0,0 +1,188 @@
+//! Layer ▸ Time: Time Stretch, Time-Reverse Layer, Enable Time Remapping, Freeze Frame and
+//! Freeze on Last Frame.
+//!
+//! Time Remap is a `timeRemap` property at the top of the layer's tree whose value is the
+//! source time (seconds) to show; its keys live in layer time like every other property.
+
+use effectcraft_keyframe::{Keyframe, Value as KV};
+use effectcraft_project::build::Ids;
+use effectcraft_project::{Layer, LayerSource, Node, ParamUi, Property};
+use effectcraft_time::Tick;
+use serde_json::{Value, json};
+
+use super::{CommandSpec, b_p, bad, f_p, has_layers, layers_p, str_p};
+use crate::{EngineError, Result, Session, cmd};
+
+/// Layers whose source has its own time (precomps and footage) can be remapped.
+fn remappable(l: &Layer) -> bool {
+    matches!(l.source, LayerSource::Comp { .. } | LayerSource::Footage { .. })
+}
+
+fn time_stretch(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, ids) = layers_p(s, p)?;
+    let reverse = str_p(p, "op") == Some("reverse");
+    let pct = f_p(p, "percent");
+    let dur = f_p(p, "duration");
+    let hold = str_p(p, "hold").unwrap_or("in").to_string();
+    let cti = s.time();
+    let comp_rate = s.project.comp(cid).ok_or(EngineError::NoComp)?.frame_rate;
+    let fd = comp_rate.frame_duration();
+    s.edit(if reverse { "Time-Reverse Layer" } else { "Time Stretch" }, None, |proj, _| {
+        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id)) {
+            let old = l.stretch;
+            if reverse {
+                // Keep the in/out points; play the visible span backwards.
+                let last = l.layer_time(l.out_point - fd);
+                l.stretch = -old;
+                l.start_time = l.in_point - Tick((last.0 as f64 * l.stretch / 100.0).round() as i64);
+                continue;
+            }
+            let span = (l.out_point - l.in_point).seconds();
+            let new = match (pct, dur) {
+                (Some(v), _) => v,
+                (None, Some(d)) if span > 0.0 => old * d / span,
+                _ => old,
+            };
+            if new.abs() < 1.0 {
+                return Err(bad("layer.timeStretch", "the stretch factor must be at least 1 %"));
+            }
+            // The hold point keeps showing the same layer time.
+            let h = match hold.as_str() {
+                "current" => cti,
+                "out" => l.out_point,
+                _ => l.in_point,
+            };
+            let lt_h = l.layer_time(h);
+            let (lin, lout) = (l.layer_time(l.in_point), l.layer_time(l.out_point));
+            l.stretch = new;
+            l.start_time = h - Tick((lt_h.0 as f64 * new / 100.0).round() as i64);
+            let (a, b) = (l.comp_time(lin), l.comp_time(lout));
+            let fr = comp_rate;
+            l.in_point = fr.snap_nearest(a.min(b));
+            l.out_point = fr.snap_nearest(a.max(b)).max(l.in_point + fr.frame_duration());
+        }
+        Ok(())
+    })?;
+    Ok(Value::Null)
+}
+
+fn remap_prop(ids: &mut Ids) -> Property {
+    let mut p = ids.prop("timeRemap", "Time Remap", KV::Scalar(0.0)).with_ui(ParamUi::Number);
+    p.ui = ParamUi::Number;
+    p
+}
+
+/// Source time (seconds) a layer shows at comp time `t` without remapping.
+fn source_secs(l: &Layer, t: Tick) -> f64 {
+    l.layer_time(t).seconds()
+}
+
+fn enable_time_remap(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, ids) = layers_p(s, p)?;
+    let want = b_p(p, "value");
+    let fd = s.project.comp(cid).ok_or(EngineError::NoComp)?.frame_duration();
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    if !comp.layers.iter().filter(|l| ids.contains(&l.id)).any(remappable) {
+        return Err(bad("layer.enableTimeRemap", "time remapping needs a footage or composition layer"));
+    }
+    let on = s.edit("Enable Time Remapping", None, |proj, _| {
+        let mut next = proj.next_id;
+        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        let mut on = false;
+        for l in comp.layers.iter_mut().filter(|l| ids.contains(&l.id) && remappable(l)) {
+            let has = l.props.get("timeRemap").is_some();
+            let target = want.unwrap_or(!has);
+            on |= target;
+            if target && !has {
+                let mut pr = remap_prop(&mut Ids(&mut next));
+                let (lin, lout) = (l.layer_time(l.in_point), l.layer_time(l.out_point));
+                let (a, b) = (lin.min(lout), lin.max(lout));
+                pr.value = KV::Scalar(source_secs(l, l.in_point));
+                pr.keys = vec![Keyframe::new(a, KV::Scalar(a.seconds())), Keyframe::new(b, KV::Scalar(b.seconds()))];
+                if lin > lout {
+                    // Reversed layers keep showing what they showed.
+                    pr.keys[0].value = KV::Scalar(source_secs(l, l.out_point - fd));
+                    pr.keys[1].value = KV::Scalar(source_secs(l, l.in_point));
+                }
+                l.props.children.insert(0, Node::Prop(pr));
+            } else if !target && has {
+                l.props.children.retain(|c| c.match_id() != "timeRemap");
+            }
+        }
+        proj.next_id = next;
+        Ok(on)
+    })?;
+    Ok(json!(on))
+}
+
+/// Freeze Frame: time remapping holding the current source frame for the whole layer.
+fn freeze(s: &mut Session, p: &Value, last: bool) -> Result<Value> {
+    let (cid, ids) = layers_p(s, p)?;
+    let cti = s.time();
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let (fd, cdur) = (comp.frame_duration(), comp.duration);
+    if !comp.layers.iter().filter(|l| ids.contains(&l.id)).any(remappable) {
+        return Err(bad("layer.freezeFrame", "freezing needs a footage or composition layer"));
+    }
+    // What each layer shows now (honouring an existing remap) — evaluated before the edit.
+    let ectx = effectcraft_render::EvalCtx { project: &s.project, comp_id: cid, comp, time: cti, expr: s.expr.as_deref() };
+    let now: Vec<(effectcraft_project::LayerId, f64)> = comp
+        .layers
+        .iter()
+        .filter(|l| ids.contains(&l.id) && remappable(l))
+        .map(|l| {
+            let at = if last { ectx.at(l.out_point - fd) } else { ectx };
+            (l.id, at.source_time(l).seconds())
+        })
+        .collect();
+    s.edit(if last { "Freeze on Last Frame" } else { "Freeze Frame" }, None, |proj, _| {
+        let mut next = proj.next_id;
+        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        for (lid, src) in &now {
+            let Some(l) = comp.layer_mut(*lid) else { continue };
+            if l.props.get("timeRemap").is_none() {
+                l.props.children.insert(0, Node::Prop(remap_prop(&mut Ids(&mut next))));
+            }
+            let lt = if last { l.layer_time(l.out_point - fd) } else { l.layer_time(cti) };
+            let lin = l.layer_time(l.in_point);
+            let pr = l.props.get_mut("timeRemap").ok_or(EngineError::NoComp)?;
+            pr.value = KV::Scalar(*src);
+            if last {
+                // Play normally up to the last frame, then hold it to the end of the comp.
+                let mut end = Keyframe::new(lt.max(lin), KV::Scalar(*src));
+                end.out_interp = effectcraft_keyframe::Interp::Hold;
+                pr.keys = vec![Keyframe::new(lin.min(lt), KV::Scalar(lin.min(lt).seconds())), end];
+                pr.keys.dedup_by_key(|k| k.time);
+                l.out_point = cdur;
+            } else {
+                pr.keys = vec![Keyframe::new(lt, KV::Scalar(*src)).hold()];
+            }
+        }
+        proj.next_id = next;
+        Ok(())
+    })?;
+    Ok(Value::Null)
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        cmd!(
+            "layer.timeStretch",
+            "Time Stretch…",
+            ["Layer", "Time"],
+            None,
+            "{layers?, percent?|duration? (s), hold?: in|current|out, op?: reverse}",
+            has_layers,
+            time_stretch
+        ),
+        cmd!("layer.timeReverse", "Time-Reverse Layer", ["Layer", "Time"], Some("Cmd+Alt+R"), "{layers?}", has_layers, |s, p| {
+            let mut p = p.clone();
+            p["op"] = json!("reverse");
+            time_stretch(s, &p)
+        }),
+        cmd!("layer.enableTimeRemap", "Enable Time Remapping", ["Layer", "Time"], Some("Cmd+Alt+T"), "{layers?, value?}", has_layers, enable_time_remap),
+        cmd!("layer.freezeFrame", "Freeze Frame", ["Layer", "Time"], None, "{layers?}", has_layers, |s, p| freeze(s, p, false)),
+        cmd!("layer.freezeOnLastFrame", "Freeze on Last Frame", ["Layer", "Time"], None, "{layers?}", has_layers, |s, p| freeze(s, p, true)),
+    ]
+}

crates/engine/src/commands/link.rs

@@ -0,0 +1,182 @@
+//! Separate Dimensions and the property pick-whip (AE-style reference expressions).
+
+use effectcraft_keyframe::{Ease, Interp, Keyframe, Value as KV};
+use effectcraft_project::{Comp, Layer, Node, ParamUi, Property, Uid};
+use effectcraft_time::{TICKS_PER_SECOND, Tick};
+use serde_json::{Value, json};
+
+use super::prop::prop_ref;
+use super::{CommandSpec, b_p, bad, has_layers, layer_mut, layer_p};
+use crate::{EngineError, Result, Session, cmd};
+
+const AXES: [(&str, &str); 3] = [("positionX", "X Position"), ("positionY", "Y Position"), ("positionZ", "Z Position")];
+
+/// Per-dimension scalar keys from a (spatial) position key list: same times and interpolation;
+/// Bezier sides get the per-dimension velocity the combined property had at the key.
+fn split_keys(keys: &[Keyframe], spatial: bool, d: usize) -> Vec<Keyframe> {
+    let h = Tick(TICKS_PER_SECOND / 2000);
+    keys.iter()
+        .map(|k| {
+            let mut s = Keyframe::new(k.time, KV::Scalar(k.value.components().get(d).copied().unwrap_or(0.0)));
+            s.in_interp = k.in_interp;
+            s.out_interp = k.out_interp;
+            s.auto_bezier = k.auto_bezier;
+            s.continuous = k.continuous;
+            s.roving = false;
+            let vel = |t: Tick| effectcraft_keyframe::velocity(keys, t, spatial).get(d).copied().unwrap_or(0.0);
+            if k.in_interp == Interp::Bezier {
+                let inf = k.in_ease.first().map(|e| e.influence).unwrap_or(1.0 / 3.0);
+                s.in_ease = vec![Ease { speed: vel(k.time - h), influence: inf }];
+            }
+            if k.out_interp == Interp::Bezier {
+                let inf = k.out_ease.first().map(|e| e.influence).unwrap_or(1.0 / 3.0);
+                s.out_ease = vec![Ease { speed: vel(k.time + h), influence: inf }];
+            }
+            s
+        })
+        .collect()
+}
+
+fn separate(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, lid) = layer_p(s, p, "prop.separateDimensions")?;
+    let want = b_p(p, "value");
+    let on = s.edit("Separate Dimensions", None, |proj, _| {
+        let mut next = proj.next_id;
+        let l = layer_mut(proj, cid, lid)?;
+        let tr = l.props.sub_mut("transform").ok_or_else(|| bad("prop.separateDimensions", "this layer has no Transform"))?;
+        let has = tr.get("positionX").is_some();
+        let target = want.unwrap_or(!has);
+        if target && !has {
+            let pos = tr.get("position").ok_or_else(|| bad("prop.separateDimensions", "no Position"))?.clone();
+            let at = tr.children.iter().position(|c| c.uid() == pos.uid).map(|i| i + 1).unwrap_or(tr.children.len());
+            let comps = pos.value.components();
+            for (d, (m, name)) in AXES.iter().enumerate().rev() {
+                let mut pr = Property::new(next, m, name, KV::Scalar(comps.get(d).copied().unwrap_or(0.0))).with_ui(ParamUi::Number);
+                next += 1;
+                pr.three_d_only = d == 2;
+                pr.keys = split_keys(&pos.keys, pos.spatial, d);
+                tr.children.insert(at, Node::Prop(pr));
+            }
+        } else if !target && has {
+            let parts: Vec<Property> = AXES.iter().filter_map(|(m, _)| tr.get(m).cloned()).collect();
+            let mut times: Vec<Tick> = parts.iter().flat_map(|p| p.keys.iter().map(|k| k.time)).collect();
+            times.sort();
+            times.dedup();
+            let at = |t: Tick| KV::Vec3([0, 1, 2].map(|d| parts.get(d).map(|p| p.value_at(t).as_f64()).unwrap_or(0.0)));
+            let pos = tr.get_mut("position").ok_or_else(|| bad("prop.separateDimensions", "no Position"))?;
+            pos.value = at(Tick::ZERO);
+            pos.keys = times.iter().map(|t| Keyframe::new(*t, at(*t))).collect();
+            if pos.keys.is_empty() {
+                pos.value = KV::Vec3([0, 1, 2].map(|d| parts.get(d).map(|p| p.value.as_f64()).unwrap_or(0.0)));
+            }
+            tr.children.retain(|c| !AXES.iter().any(|(m, _)| c.match_id() == *m));
+        }
+        proj.next_id = next;
+        Ok(target)
+    })?;
+    Ok(json!(on))
+}
+
+// ---------------------------------------------------------------- pick-whip
+
+/// `X Position` → `xPosition`, `Mask Path` → `maskPath`.
+fn camel(name: &str) -> String {
+    let mut out = String::new();
+    for (i, w) in name.split(|c: char| !c.is_alphanumeric()).filter(|w| !w.is_empty()).enumerate() {
+        let mut cs = w.chars();
+        if let Some(f) = cs.next() {
+            if i == 0 {
+                out.extend(f.to_lowercase());
+            } else {
+                out.extend(f.to_uppercase());
+            }
+            out.push_str(cs.as_str());
+        }
+    }
+    out
+}
+
+fn quote(s: &str) -> String {
+    serde_json::to_string(s).unwrap_or_else(|_| format!("\"{s}\""))
+}
+
+/// The AE expression reference to property `uid` of `target` as seen from a property of `from`.
+pub(crate) fn reference(comp: &Comp, from: &Layer, target: &Layer, uid: Uid) -> Option<String> {
+    let chain = target.props.node_chain(uid)?;
+    let mut parts: Vec<String> = vec![];
+    let mut pending: Option<&str> = None;
+    let mut in_effect = false;
+    for n in chain {
+        if let Some(f) = pending.take() {
+            parts.push(format!("{f}({})", quote(n.name())));
+            in_effect |= f == "effect";
+            continue;
+        }
+        match (n, n.match_id()) {
+            (Node::Group(_), "masks") => pending = Some("mask"),
+            (Node::Group(_), "effects") => pending = Some("effect"),
+            (Node::Group(_), "contents") => pending = Some("content"),
+            (Node::Group(_), "transform") if !in_effect => parts.push("transform".into()),
+            (Node::Group(_), "text") if !in_effect => parts.push("text".into()),
+            (Node::Prop(_), "sourceText") => parts.push("sourceText".into()),
+            _ if in_effect => parts.push(format!("({})", quote(n.name()))),
+            _ => parts.push(camel(n.name())),
+        }
+    }
+    let mut out = if from.id == target.id { String::new() } else { format!("thisComp.layer({}).", quote(&target.name)) };
+    let _ = comp;
+    for (i, p) in parts.iter().enumerate() {
+        if i > 0 && !p.starts_with('(') {
+            out.push('.');
+        }
+        out.push_str(p);
+    }
+    Some(out)
+}
+
+/// Dimensions an expression sees (2D layers see 2D Position/Scale/Anchor).
+fn dims(l: &Layer, p: &Property) -> usize {
+    match &p.value {
+        KV::Vec3(_) if p.shown_dims == 2 && !l.is_3d() => 2,
+        v => v.components().len().max(1),
+    }
+}
+
+fn pick_whip(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, lid, uid) = prop_ref(s, p, "prop.pickWhip")?;
+    let t = p.get("target").ok_or_else(|| bad("prop.pickWhip", "missing `target` {layer, path|prop}"))?;
+    let (_, tl, tu) = prop_ref(s, t, "prop.pickWhip")?;
+    if (tl, tu) == (lid, uid) {
+        return Err(bad("prop.pickWhip", "a property can't reference itself"));
+    }
+    let comp = s.project.comp(cid).ok_or(EngineError::NoComp)?;
+    let from = comp.layer(lid).ok_or(EngineError::NoComp)?;
+    let target = comp.layer(tl).ok_or(EngineError::NoComp)?;
+    let r = reference(comp, from, target, tu).ok_or_else(|| bad("prop.pickWhip", "no such target property"))?;
+    let (me, them) = (from.props.find(uid).ok_or(EngineError::NoComp)?, target.props.find(tu).ok_or(EngineError::NoComp)?);
+    let (dm, dt) = (dims(from, me), dims(target, them));
+    let text = if dt == 1 && dm > 1 {
+        format!("temp = {r};\n[{}]", vec!["temp"; dm].join(", "))
+    } else if dt > 1 && dm == 1 {
+        format!("{r}[0]")
+    } else {
+        r
+    };
+    s.execute("prop.setExpression", json!({"layer": lid.0, "prop": uid, "expression": text}))?;
+    Ok(json!(text))
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        cmd!("prop.separateDimensions", "Separate Dimensions", ["Animation"], None, "{layer?, value?}", has_layers, separate),
+        cmd!(
+            "prop.pickWhip",
+            "Pick Whip (Link Property)",
+            [],
+            None,
+            "{layer?, path|prop, target: {layer, path|prop}} → sets an AE reference expression",
+            has_layers,
+            pick_whip
+        ),
+    ]
+}

crates/engine/src/commands/mask.rs

@@ -0,0 +1,260 @@
+//! Masks drawn and edited in the viewer: Pen tool (new mask, add vertex, Bezier tangents, close
+//! path), vertex selection, moving and deleting vertices, and Layer ▸ Mask ▸ Remove (All).
+//!
+//! Coordinates are in layer space. Edits of an animated Mask Path set a key at the current time.
+
+use effectcraft_keyframe::{ShapePath, Value as KV};
+use effectcraft_project::build::{self, Ids};
+use effectcraft_project::{Layer, MaskMode, PropGroup, Uid};
+use serde_json::{Value, json};
+
+use super::{CommandSpec, b_p, bad, has_comp, has_layers, layer_mut, layer_p, merge_p, resolve_layer, str_p};
+use crate::{EngineError, Result, Session, VertexRef, cmd};
+
+fn pt(v: Option<&Value>) -> Option<[f64; 2]> {
+    let a = v?.as_array()?;
+    Some([a.first()?.as_f64()?, a.get(1)?.as_f64()?])
+}
+
+fn pts(v: Option<&Value>) -> Vec<[f64; 2]> {
+    v.and_then(Value::as_array).map(|a| a.iter().filter_map(|p| pt(Some(p))).collect()).unwrap_or_default()
+}
+
+/// Find a mask group by uid, 1-based index or name.
+fn find_mask<'a>(masks: &'a mut PropGroup, key: &Value) -> Option<&'a mut PropGroup> {
+    let i = match key {
+        Value::Number(n) => {
+            let n = n.as_u64()?;
+            masks.children.iter().position(|c| c.uid() == n).or_else(|| (n as usize).checked_sub(1).filter(|i| *i < masks.children.len()))?
+        }
+        Value::String(s) => masks.children.iter().position(|c| c.name() == s)?,
+        _ => return None,
+    };
+    masks.children.get_mut(i)?.as_group_mut()
+}
+
+/// Edit the mask path of (layer, mask) at the current time.
+fn edit_path<T>(s: &mut Session, p: &Value, label: &str, f: impl FnOnce(&mut ShapePath) -> Result<T>) -> Result<(Uid, T)> {
+    let (cid, lid) = layer_p(s, p, label)?;
+    let key = p.get("mask").cloned().ok_or_else(|| bad(label, "missing `mask` (uid, index or name)"))?;
+    let t = s.time();
+    s.edit(label, merge_p(p), |proj, _| {
+        let l = layer_mut(proj, cid, lid)?;
+        let lt = l.layer_time(t);
+        let masks = l.props.sub_mut("masks").ok_or_else(|| bad(label, "this layer has no masks"))?;
+        let g = find_mask(masks, &key).ok_or_else(|| bad(label, "no such mask"))?;
+        let uid = g.uid;
+        let pr = g.get_mut("path").ok_or_else(|| bad(label, "mask has no path"))?;
+        let KV::Path(mut sp) = pr.value_at(lt) else { return Err(bad(label, "not a path")) };
+        let r = f(&mut sp)?;
+        pr.set_value_at(lt, KV::Path(sp));
+        Ok((uid, r))
+    })
+}
+
+/// Pen tool: a new (open by default) mask from points.
+fn new_mask(s: &mut Session, p: &Value) -> Result<Value> {
+    let (cid, lid) = layer_p(s, p, "mask.new")?;
+    let v = pts(p.get("vertices"));
+    if v.is_empty() {
+        return Err(bad("mask.new", "need `vertices` [[x,y], …] in layer space"));
+    }
+    let n = v.len();
+    let mut ins = pts(p.get("inTangents"));
+    let mut outs = pts(p.get("outTangents"));
+    ins.resize(n, [0.0; 2]);
+    outs.resize(n, [0.0; 2]);
+    let path = ShapePath { vertices: v, in_tangents: ins, out_tangents: outs, closed: b_p(p, "closed").unwrap_or(false) };
+    let mode = str_p(p, "mode").and_then(MaskMode::from_name).unwrap_or(MaskMode::Add);
+    let uid = s.edit("New Mask", None, |proj, st| {
+        let mut next = proj.next_id;
+        let l = layer_mut(proj, cid, lid)?;
+        let masks = l.props.sub_mut("masks").ok_or_else(|| bad("mask.new", "this layer can't have masks"))?;
+        let k = masks.children.len();
+        let g = build::mask(&mut Ids(&mut next), &format!("Mask {}", k + 1), path, mode, build::MASK_COLORS[k % build::MASK_COLORS.len()]);
+        let uid = g.uid;
+        masks.children.push(g.into());
+        proj.next_id = next;
+        st.selected_vertices = vec![VertexRef { layer: lid, mask: uid, index: n - 1 }];
+        Ok(uid)
+    })?;
+    Ok(json!({"mask": uid}))
+}
+
+fn add_vertex(s: &mut Session, p: &Value) -> Result<Value> {
+    let point = pt(p.get("point")).ok_or_else(|| bad("mask.addVertex", "missing `point` [x,y]"))?;
+    let tin = pt(p.get("in")).unwrap_or([0.0; 2]);
+    let tout = pt(p.get("out")).unwrap_or([0.0; 2]);
+    let at = p.get("index").and_then(Value::as_u64).map(|i| i as usize);
+    let (_, lid) = layer_p(s, p, "mask.addVertex")?;
+    let (uid, i) = edit_path(s, p, "mask.addVertex", |sp| {
+        let i = at.unwrap_or(sp.vertices.len()).min(sp.vertices.len());
+        sp.vertices.insert(i, point);
+        sp.in_tangents.insert(i, tin);
+        sp.out_tangents.insert(i, tout);
+        Ok(i)
+    })?;
+    s.state.selected_vertices = vec![VertexRef { layer: lid, mask: uid, index: i }];
+    Ok(json!(i))
+}
+
+fn set_vertex(s: &mut Session, p: &Value) -> Result<Value> {
+    let i = p.get("index").and_then(Value::as_u64).ok_or_else(|| bad("mask.setVertex", "missing `index`"))? as usize;
+    let (point, tin, tout) = (pt(p.get("point")), pt(p.get("in")), pt(p.get("out")));
+    edit_path(s, p, "mask.setVertex", |sp| {
+        if i >= sp.vertices.len() {
+            return Err(bad("mask.setVertex", "no such vertex"));
+        }
+        if let Some(v) = point {
+            sp.vertices[i] = v;
+        }
+        if let Some(v) = tin {
+            sp.in_tangents[i] = v;
+        }
+        if let Some(v) = tout {
+            sp.out_tangents[i] = v;
+        }
+        Ok(())
+    })?;
+    Ok(Value::Null)
+}
+
+fn set_closed(s: &mut Session, p: &Value) -> Result<Value> {
+    let c = b_p(p, "closed").unwrap_or(true);
+    edit_path(s, p, "mask.setClosed", |sp| {
+        sp.closed = c;
+        Ok(())
+    })?;
+    Ok(json!(c))
+}
+
+/// Selected (or given) vertices grouped per (layer, mask).
+fn vertex_groups(s: &Session, p: &Value) -> Result<std::collections::BTreeMap<(u64, Uid), Vec<usize>>> {
+    let comp = s.active_comp().ok_or(EngineError::NoComp)?;
+    let mut g: std::collections::BTreeMap<(u64, Uid), Vec<usize>> = Default::default();
+    if let Some(Value::Array(a)) = p.get("vertices") {
+        for v in a {
+            let l = v.get("layer").and_then(|x| resolve_layer(comp, x)).ok_or_else(|| bad("mask", "vertex needs `layer`"))?;
+            let m = v.get("mask").and_then(Value::as_u64).ok_or_else(|| bad("mask", "vertex needs `mask` uid"))?;
+            let i = v.get("index").and_then(Value::as_u64).ok_or_else(|| bad("mask", "vertex needs `index`"))?;
+            g.entry((l.0, m)).or_default().push(i as usize);
+        }
+    } else {
+        for v in &s.state.selected_vertices {
+            g.entry((v.layer.0, v.mask)).or_default().push(v.index);
+        }
+    }
+    Ok(g)
+}
+
+fn select_vertices(s: &mut Session, p: &Value) -> Result<Value> {
+    let g = vertex_groups(s, &json!({"vertices": p.get("vertices").cloned().unwrap_or(json!([]))}))?;
+    let sel: Vec<VertexRef> =
+        g.into_iter().flat_map(|((l, m), is)| is.into_iter().map(move |i| VertexRef { layer: effectcraft_project::LayerId(l), mask: m, index: i })).collect();
+    if b_p(p, "add").unwrap_or(false) {
+        for v in sel {
+            if let Some(i) = s.state.selected_vertices.iter().position(|x| *x == v) {
+                if b_p(p, "toggle").unwrap_or(false) {
+                    s.state.selected_vertices.remove(i);
+                }
+            } else {
+                s.state.selected_vertices.push(v);
+            }
+        }
+    } else {
+        s.state.selected_vertices = sel;
+    }
+    Ok(json!(s.state.selected_vertices.len()))
+}
+
+fn has_vertices(s: &Session) -> std::result::Result<(), String> {
+    has_comp(s)?;
+    if s.state.selected_vertices.is_empty() { Err("select mask vertices first".into()) } else { Ok(()) }
+}
+
+/// Apply `f` to the selected vertices' paths (each mask once).
+fn edit_vertices(s: &mut Session, p: &Value, label: &str, f: impl Fn(&mut ShapePath, &[usize])) -> Result<Value> {
+    let cid = s.active_comp_id().ok_or(EngineError::NoComp)?;
+    let groups = vertex_groups(s, p)?;
+    let t = s.time();
+    s.edit(label, merge_p(p), |proj, _| {
+        let comp = proj.comp_mut(cid).ok_or(EngineError::NoComp)?;
+        for ((l, m), idx) in &groups {
+            let Some(layer) = comp.layer_mut(effectcraft_project::LayerId(*l)) else { continue };
+            let lt = layer.layer_time(t);
+            let Some(pr) = layer.props.sub_mut("masks").and_then(|ms| ms.find_group_mut(*m)).and_then(|g| g.get_mut("path")) else { continue };
+            let KV::Path(mut sp) = pr.value_at(lt) else { continue };
+            f(&mut sp, idx);
+            pr.set_value_at(lt, KV::Path(sp));
+        }
+        Ok(())
+    })?;
+    Ok(json!(groups.values().map(Vec::len).sum::<usize>()))
+}
+
+fn move_vertices(s: &mut Session, p: &Value) -> Result<Value> {
+    let d = pt(p.get("delta")).ok_or_else(|| bad("mask.moveVertices", "missing `delta` [dx,dy] (layer space)"))?;
+    edit_vertices(s, p, "Move Mask Vertices", |sp, idx| {
+        for &i in idx {
+            if let Some(v) = sp.vertices.get_mut(i) {
+                v[0] += d[0];
+                v[1] += d[1];
+            }
+        }
+    })
+}
+
+fn delete_vertices(s: &mut Session, p: &Value) -> Result<Value> {
+    let n = edit_vertices(s, p, "Delete Mask Vertices", |sp, idx| {
+        let mut idx = idx.to_vec();
+        idx.sort_unstable();
+        idx.dedup();
+        for &i in idx.iter().rev() {
+            if i < sp.vertices.len() {
+                sp.vertices.remove(i);
+                sp.in_tangents.remove(i);
+                sp.out_tangents.remove(i);
+            }
+        }
+        if sp.vertices.len() < 3 {
+            sp.closed = false;
+        }
+    })?;
+    s.state.selected_vertices.clear();
+    Ok(n)
+}
+
+fn remove_masks(s: &mut Session, p: &Value, all: bool) -> Result<Value> {
+    let (cid, lid) = layer_p(s, p, "mask.remove")?;
+    let key = p.get("mask").cloned();
+    if !all && key.is_none() {
+        return Err(bad("mask.remove", "missing `mask`"));
+    }
+    s.edit(if all { "Remove All Masks" } else { "Remove Mask" }, None, |proj, st| {
+        let l: &mut Layer = layer_mut(proj, cid, lid)?;
+        let masks = l.props.sub_mut("masks").ok_or_else(|| bad("mask.remove", "this layer has no masks"))?;
+        if all {
+            masks.children.clear();
+        } else if let Some(k) = &key {
+            let uid = find_mask(masks, k).map(|g| g.uid).ok_or_else(|| bad("mask.remove", "no such mask"))?;
+            masks.children.retain(|c| c.uid() != uid);
+        }
+        st.selected_vertices.retain(|v| v.layer != lid);
+        Ok(())
+    })?;
+    Ok(Value::Null)
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        cmd!("mask.new", "New Mask from Points", [], None, "{layer?, vertices: [[x,y]…], inTangents?, outTangents?, closed?, mode?}", has_layers, new_mask),
+        cmd!("mask.addVertex", "Add Mask Vertex", [], None, "{layer?, mask, point: [x,y], in?, out?, index?}", has_layers, add_vertex),
+        cmd!("mask.setVertex", "Set Mask Vertex", [], None, "{layer?, mask, index, point?, in?, out?, merge?}", has_layers, set_vertex),
+        cmd!("mask.setClosed", "Closed", ["Layer", "Mask and Shape Path"], None, "{layer?, mask, closed?}", has_layers, set_closed),
+        cmd!("mask.selectVertices", "Select Mask Vertices", [], None, "{vertices: [{layer, mask, index}], add?, toggle?}", has_comp, select_vertices),
+        cmd!("mask.moveVertices", "Move Mask Vertices", [], None, "{vertices?: [{layer, mask, index}], delta: [dx,dy], merge?}", has_vertices, move_vertices),
+        cmd!("mask.deleteVertices", "Delete Mask Vertices", [], None, "{vertices?}", has_vertices, delete_vertices),
+        cmd!("mask.remove", "Remove Mask", ["Layer", "Mask"], None, "{layer?, mask}", has_layers, |s, p| remove_masks(s, p, false)),
+        cmd!("mask.removeAll", "Remove All Masks", ["Layer", "Mask"], None, "{layer?}", has_layers, |s, p| remove_masks(s, p, true)),
+    ]
+}

crates/engine/src/commands/mod.rs

@@ -1,12 +1,16 @@
 //! The command registry. Ids follow After Effects' menu structure; every menu item, panel button,
 //! shortcut and viewer/timeline gesture maps to one of these.
 
+mod anim;
 mod comp;
 mod edit;
 mod effect;
 mod file;
 mod help;
 mod layer;
+mod layer_time;
+mod link;
+mod mask;
 mod prop;
 mod query;
 mod render_queue;
@@ -69,7 +73,11 @@ pub fn command_specs() -> &'static [CommandSpec] {
         v.extend(edit::specs());
         v.extend(comp::specs());
         v.extend(layer::specs());
+        v.extend(layer_time::specs());
         v.extend(prop::specs());
+        v.extend(anim::specs());
+        v.extend(link::specs());
+        v.extend(mask::specs());
         v.extend(effect::specs());
         v.extend(time::specs());
         v.extend(render_queue::specs());

crates/engine/src/commands/prop.rs

@@ -9,7 +9,7 @@ use super::{CommandSpec, b_p, bad, f_p, has_comp, has_keys, has_layers, layer_mu
 use crate::{EngineError, KeyRef, Result, Session, cmd, query};
 
 /// Resolve `{layer, path}` (or `{layer, prop: uid}`) to (comp, layer, prop uid).
-fn prop_ref(s: &Session, p: &Value, cmd: &str) -> Result<(ItemId, LayerId, Uid)> {
+pub(crate) fn prop_ref(s: &Session, p: &Value, cmd: &str) -> Result<(ItemId, LayerId, Uid)> {
     let (cid, lid) = layer_p(s, p, cmd)?;
     let layer = s.project.comp(cid).and_then(|c| c.layer(lid)).ok_or(EngineError::NoComp)?;
     if let Some(u) = p.get("prop").and_then(Value::as_u64) {
@@ -38,10 +38,44 @@ fn with_prop<T>(
     })
 }
 
+/// An explicit key time (layer seconds) moved onto the nearest comp frame.
+fn snapped_key_time(s: &Session, cid: ItemId, lid: LayerId, p: &Value) -> Option<Tick> {
+    let t = Tick::from_seconds_f64(f_p(p, "time")?);
+    let comp = s.project.comp(cid)?;
+    let l = comp.layer(lid)?;
+    Some(l.layer_time(comp.frame_rate.snap_nearest(l.comp_time(t))))
+}
+
 fn set(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, lid, uid) = prop_ref(s, p, "prop.set")?;
+    // Position with Separate Dimensions: write the X/Y/Z Position properties instead.
+    if let Some(l) = s.project.comp(cid).and_then(|c| c.layer(lid))
+        && let Some(tr) = l.transform()
+        && tr.get("position").is_some_and(|pr| pr.uid == uid)
+        && tr.get("positionX").is_some()
+        && let Some(Value::Array(a)) = p.get("value")
+    {
+        let mut out = vec![];
+        let three = l.is_3d();
+        for (d, m) in ["positionX", "positionY", "positionZ"].iter().enumerate() {
+            if d == 2 && (!three || a.len() < 3) {
+                continue;
+            }
+            if let Some(v) = a.get(d) {
+                let mut q = p.clone();
+                q["path"] = json!(format!("transform/{m}"));
+                q["layer"] = json!(lid.0);
+                if let Some(o) = q.as_object_mut() {
+                    o.remove("prop");
+                }
+                q["value"] = v.clone();
+                out.push(set(s, &q)?);
+            }
+        }
+        return Ok(json!(out));
+    }
     let v = p.get("value").ok_or_else(|| bad("prop.set", "missing `value`"))?.clone();
-    let at = f_p(p, "time").map(Tick::from_seconds_f64);
+    let at = snapped_key_time(s, cid, lid, p);
     let out = with_prop(s, "Change Property", merge_p(p), cid, lid, uid, |pr, lt| {
         let cur = pr.value_at(lt);
         let mut nv = cur.coerce_json(&v).ok_or_else(|| bad("prop.set", format!("can't use {v} for a {} property", cur.kind_name())))?;
@@ -87,7 +121,7 @@ fn toggle_anim(s: &mut Session, p: &Value) -> Result<Value> {
 
 fn add_key(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, lid, uid) = prop_ref(s, p, "prop.addKey")?;
-    let at = f_p(p, "time").map(Tick::from_seconds_f64);
+    let at = snapped_key_time(s, cid, lid, p);
     let value = p.get("value").cloned();
     with_prop(s, "Add Keyframe", None, cid, lid, uid, |pr, lt| {
         let t = at.unwrap_or(lt);
@@ -128,8 +162,18 @@ fn toggle_key(s: &mut Session, p: &Value) -> Result<Value> {
 fn set_expr(s: &mut Session, p: &Value) -> Result<Value> {
     let (cid, lid, uid) = prop_ref(s, p, "prop.setExpression")?;
     let text = p.get("expression").and_then(Value::as_str).map(str::to_string);
-    let enabled = b_p(p, "enabled");
-    with_prop(s, "Expression", merge_p(p), cid, lid, uid, |pr, _| {
+    let mut enabled = b_p(p, "enabled");
+    // A syntax error keeps the text but disables the expression (AE shows the warning bar).
+    let error = match (&text, s.expr_check) {
+        (Some(t), Some(check)) if !t.trim().is_empty() => check(t).err(),
+        _ => None,
+    };
+    if error.is_some() {
+        enabled = Some(false);
+    }
+    // Alt-click on a stopwatch starts with the property's own reference (`transform.opacity`).
+    let def = s.project.comp(cid).and_then(|c| c.layer(lid).and_then(|l| super::link::reference(c, l, l, uid))).unwrap_or_else(|| "value".into());
+    let r = with_prop(s, "Expression", merge_p(p), cid, lid, uid, |pr, _| {
         match (&text, enabled) {
             (Some(t), _) if t.trim().is_empty() => pr.expr = None,
             (Some(t), e) => pr.expr = Some(effectcraft_project::Expression { text: t.clone(), enabled: e.unwrap_or(true) }),
@@ -137,20 +181,20 @@ fn set_expr(s: &mut Session, p: &Value) -> Result<Value> {
                 if let Some(x) = &mut pr.expr {
                     x.enabled = e;
                 } else if e {
-                    pr.expr = Some(effectcraft_project::Expression { text: default_expr(pr), enabled: true });
+                    pr.expr = Some(effectcraft_project::Expression { text: def.clone(), enabled: true });
                 }
             }
             (None, None) => {
-                pr.expr = if pr.expr.is_some() { None } else { Some(effectcraft_project::Expression { text: default_expr(pr), enabled: true }) };
+                pr.expr = if pr.expr.is_some() { None } else { Some(effectcraft_project::Expression { text: def.clone(), enabled: true }) };
             }
         }
         Ok(json!(pr.expr.as_ref().map(|e| e.text.clone())))
-    })
-}
-
-fn default_expr(pr: &Property) -> String {
-    let _ = pr;
-    "value".to_string()
+    })?;
+    if let Some(e) = error {
+        s.toast(format!("Expression disabled: {e}"));
+        return Ok(json!({"expression": r, "error": e}));
+    }
+    Ok(r)
 }
 
 fn reset(s: &mut Session, p: &Value) -> Result<Value> {
@@ -225,7 +269,7 @@ fn select_keys(s: &mut Session, p: &Value) -> Result<Value> {
 }
 
 /// Apply `f` to every selected key; keeps the selection pointing at moved keys.
-fn edit_keys(s: &mut Session, label: &str, merge: Option<&str>, f: impl Fn(&mut Vec<Keyframe>, usize, &mut Tick) -> bool) -> Result<Value> {
+pub(crate) fn edit_keys(s: &mut Session, label: &str, merge: Option<&str>, f: impl Fn(&mut Vec<Keyframe>, usize, &mut Tick) -> bool) -> Result<Value> {
     let cid = s.active_comp_id().ok_or(EngineError::NoComp)?;
     let sel = s.state.selected_keys.clone();
     s.edit(label, merge, |proj, st| {
@@ -262,8 +306,14 @@ fn edit_keys(s: &mut Session, label: &str, merge: Option<&str>, f: impl Fn(&mut
             for t in keep_times {
                 new_sel.push(KeyRef { layer: lid, prop: uid, time: t });
             }
-            if pr.keys.is_empty() {
-                // Deleting every key leaves the value at the last key.
+            // Roving keys follow their neighbours: re-time and keep the selection on them.
+            let before: Vec<Tick> = pr.keys.iter().map(|k| k.time).collect();
+            if effectcraft_keyframe::retime_roving(&mut pr.keys, pr.spatial) {
+                for r in new_sel.iter_mut().filter(|r| r.layer == lid && r.prop == uid) {
+                    if let Some(i) = before.iter().position(|t| *t == r.time) {
+                        r.time = pr.keys[i].time;
+                    }
+                }
             }
         }
         st.selected_keys = new_sel;
@@ -319,8 +369,56 @@ fn interpolation(s: &mut Session, p: &Value) -> Result<Value> {
     let both = parse("interpolation");
     let inn = parse("in").or(both);
     let out = parse("out").or(both);
-    let auto = b_p(p, "autoBezier");
+    // Temporal interpolation by dialog name: linear|bezier|continuousBezier|autoBezier|hold.
+    let temporal = str_p(p, "interpolation").map(|v| v.to_ascii_lowercase());
+    let mut auto = b_p(p, "autoBezier");
+    let mut continuous = b_p(p, "continuous");
+    match temporal.as_deref() {
+        Some("autobezier" | "auto") => auto = Some(true),
+        Some("continuousbezier" | "continuous") => {
+            continuous = Some(true);
+            auto = Some(false);
+        }
+        Some("linear" | "bezier" | "hold") => {
+            auto = auto.or(Some(false));
+            continuous = continuous.or(Some(false));
+        }
+        _ => {}
+    }
+    let inn = if matches!(temporal.as_deref(), Some("autobezier" | "auto" | "continuousbezier" | "continuous")) { inn.or(Some(Interp::Bezier)) } else { inn };
+    let out = if matches!(temporal.as_deref(), Some("autobezier" | "auto" | "continuousbezier" | "continuous")) { out.or(Some(Interp::Bezier)) } else { out };
+    let spatial = str_p(p, "spatial").map(|v| v.to_ascii_lowercase());
+    let roving = b_p(p, "roving");
     edit_keys(s, "Keyframe Interpolation", None, move |keys, i, _| {
+        if let Some(sp) = spatial.as_deref() {
+            let (tin, tout) = effectcraft_keyframe::spatial_tangents(keys, i);
+            let k = &mut keys[i];
+            match sp {
+                "linear" => {
+                    k.spatial_auto = false;
+                    k.spatial_continuous = false;
+                    k.spatial_in = [0.0; 3];
+                    k.spatial_out = [0.0; 3];
+                }
+                "bezier" | "continuous" | "continuousbezier" => {
+                    k.spatial_auto = false;
+                    k.spatial_in = tin;
+                    k.spatial_out = tout;
+                    k.spatial_continuous = sp != "bezier";
+                }
+                "auto" | "autobezier" => {
+                    k.spatial_auto = true;
+                    k.spatial_continuous = false;
+                }
+                _ => {}
+            }
+        }
+        if let Some(r) = roving {
+            keys[i].roving = r;
+        }
+        if let Some(c) = continuous {
+            keys[i].continuous = c;
+        }
         let n = keys[i].value.dims().max(1);
         if let Some(x) = inn {
             keys[i].in_interp = x;
@@ -339,6 +437,24 @@ fn interpolation(s: &mut Session, p: &Value) -> Result<Value> {
             if a {
                 keys[i].in_interp = Interp::Bezier;
                 keys[i].out_interp = Interp::Bezier;
+                keys[i].continuous = false;
+            }
+        }
+        if keys[i].continuous && !keys[i].auto_bezier {
+            // Continuous Bezier: one speed through the key (average of both sides).
+            let k = &mut keys[i];
+            k.in_interp = Interp::Bezier;
+            k.out_interp = Interp::Bezier;
+            if k.in_ease.len() != n {
+                k.in_ease = vec![Ease::default(); n];
+            }
+            if k.out_ease.len() != n {
+                k.out_ease = vec![Ease::default(); n];
+            }
+            for d in 0..n {
+                let sp = (k.in_ease[d].speed + k.out_ease[d].speed) / 2.0;
+                k.in_ease[d].speed = sp;
+                k.out_ease[d].speed = sp;
             }
         }
         false
@@ -353,41 +469,67 @@ fn toggle_hold(s: &mut Session, _: &Value) -> Result<Value> {
     })
 }
 
+/// A number or a per-dimension array of numbers.
+fn nums_p(p: &Value, k: &str, scale: f64) -> Option<Vec<f64>> {
+    match p.get(k)? {
+        Value::Array(a) => Some(a.iter().filter_map(Value::as_f64).map(|v| v * scale).collect()),
+        v => v.as_f64().map(|v| vec![v * scale]),
+    }
+}
+
 fn velocity(s: &mut Session, p: &Value) -> Result<Value> {
-    let in_speed = f_p(p, "inSpeed");
-    let in_inf = f_p(p, "inInfluence").map(|v| v / 100.0);
-    let out_speed = f_p(p, "outSpeed");
-    let out_inf = f_p(p, "outInfluence").map(|v| v / 100.0);
+    let mut in_speed = nums_p(p, "inSpeed", 1.0);
+    let mut in_inf = nums_p(p, "inInfluence", 0.01);
+    let mut out_speed = nums_p(p, "outSpeed", 1.0);
+    let mut out_inf = nums_p(p, "outInfluence", 0.01);
+    // "Continuous" in the dialog: outgoing velocity follows incoming.
+    let continuous = b_p(p, "continuous");
+    if continuous == Some(true) {
+        if out_speed.is_none() {
+            out_speed = in_speed.clone();
+        }
+        if in_speed.is_none() {
+            in_speed = out_speed.clone();
+        }
+        if out_inf.is_none() {
+            out_inf = in_inf.clone();
+        }
+        if in_inf.is_none() {
+            in_inf = out_inf.clone();
+        }
+    }
     edit_keys(s, "Keyframe Velocity", merge_p(p), move |keys, i, _| {
         let n = keys[i].value.dims().max(1);
+        // Current presentation of each side, so unspecified parts keep their values.
+        let cur = |keys: &[Keyframe], out: bool| -> Vec<Ease> {
+            (0..n).map(|d| effectcraft_keyframe::side_ease(keys, i, d, false, out).unwrap_or(Ease::EASY)).collect()
+        };
+        let cur_in = cur(keys, false);
+        let cur_out = cur(keys, true);
         let k = &mut keys[i];
-        if in_speed.is_some() || in_inf.is_some() {
-            k.in_interp = Interp::Bezier;
-            if k.in_ease.is_empty() {
-                k.in_ease = vec![Ease::default(); n];
+        let apply = |list: &mut Vec<Ease>, base: Vec<Ease>, sp: &Option<Vec<f64>>, inf: &Option<Vec<f64>>| {
+            if list.len() != n {
+                *list = base;
             }
-            for e in &mut k.in_ease {
-                if let Some(v) = in_speed {
-                    e.speed = v;
+            for (d, e) in list.iter_mut().enumerate() {
+                if let Some(v) = sp.as_ref().and_then(|v| v.get(d).or(v.first())) {
+                    e.speed = *v;
                 }
-                if let Some(v) = in_inf {
+                if let Some(v) = inf.as_ref().and_then(|v| v.get(d).or(v.first())) {
                     e.influence = v.clamp(0.001, 1.0);
                 }
             }
+        };
+        if in_speed.is_some() || in_inf.is_some() {
+            k.in_interp = Interp::Bezier;
+            apply(&mut k.in_ease, cur_in, &in_speed, &in_inf);
         }
         if out_speed.is_some() || out_inf.is_some() {
             k.out_interp = Interp::Bezier;
-            if k.out_ease.is_empty() {
-                k.out_ease = vec![Ease::default(); n];
-            }
-            for e in &mut k.out_ease {
-                if let Some(v) = out_speed {
-                    e.speed = v;
-                }
-                if let Some(v) = out_inf {
-                    e.influence = v.clamp(0.001, 1.0);
-                }
-            }
+            apply(&mut k.out_ease, cur_out, &out_speed, &out_inf);
+        }
+        if let Some(c) = continuous {
+            k.continuous = c;
         }
         k.auto_bezier = false;
         false
@@ -451,7 +593,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Keyframe Interpolation…",
             ["Animation"],
             Some("Cmd+Alt+K"),
-            "{interpolation?|in?|out?: linear|bezier|hold, autoBezier?}",
+            "{interpolation?: linear|bezier|continuousBezier|autoBezier|hold, in?|out?: linear|bezier|hold, autoBezier?, continuous?, spatial?: linear|bezier|continuousBezier|autoBezier, roving?}",
             has_keys,
             interpolation
         ),
@@ -460,7 +602,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Keyframe Velocity…",
             ["Animation"],
             Some("Cmd+Shift+K"),
-            "{inSpeed?, inInfluence? %, outSpeed?, outInfluence? %}",
+            "{inSpeed?, inInfluence? %, outSpeed?, outInfluence? % (numbers or per-dimension arrays), continuous?}",
             has_keys,
             velocity
         ),

crates/engine/src/demo.rs

@@ -11,8 +11,9 @@ use effectcraft_time::{FrameRate, Tick};
 
 pub const MAIN_COMP: &str = "EffectCraft Intro";
 
+/// Seconds → the nearest frame of the demo's 29.97 fps comps (AE keeps times frame-aligned).
 fn t(s: f64) -> Tick {
-    Tick::from_seconds_f64(s)
+    FrameRate::FPS_29_97.snap_nearest(Tick::from_seconds_f64(s))
 }
 
 fn hex(h: &str) -> [f64; 4] {

crates/engine/src/lib.rs

@@ -93,6 +93,24 @@ pub struct KeyRef {
     pub time: Tick,
 }
 
+/// Keyframes of one property on the keyframe clipboard.
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+pub struct KeyClip {
+    pub layer: LayerId,
+    /// Match-id path relative to the layer (`transform/position`), portable between layers.
+    pub path: String,
+    /// Keys with times relative to the earliest copied key (layer time).
+    pub keys: Vec<effectcraft_keyframe::Keyframe>,
+}
+
+/// A selected mask vertex: layer, mask group uid, vertex index.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Serialize, Deserialize)]
+pub struct VertexRef {
+    pub layer: LayerId,
+    pub mask: Uid,
+    pub index: usize,
+}
+
 /// Editing state that commands depend on (headless-relevant, serde for agents).
 #[derive(Clone, Debug, Default, Serialize, Deserialize)]
 pub struct EditorState {
@@ -109,6 +127,15 @@ pub struct EditorState {
     /// Layer clipboard (serialized layers) and keyframe clipboard.
     #[serde(skip)]
     pub clipboard: Vec<Layer>,
+    /// Copied keyframes (times relative to the earliest copied key).
+    #[serde(skip)]
+    pub key_clipboard: Vec<KeyClip>,
+    /// The last copy was keyframes (Paste pastes keys at the CTI).
+    #[serde(skip)]
+    pub clip_is_keys: bool,
+    /// Selected mask vertices (viewer Selection tool / pen).
+    #[serde(default)]
+    pub selected_vertices: Vec<VertexRef>,
     pub snapping: bool,
     /// Last applied effect id (Effect ▸ last effect).
     pub last_effect: Option<String>,
@@ -133,6 +160,8 @@ pub struct Session {
     pub services: Arc<dyn Services>,
     pub footage: Arc<dyn FootageSource>,
     pub expr: Option<Arc<dyn ExprHost>>,
+    /// Expression syntax checker (set by the host that links the expression engine).
+    pub expr_check: Option<fn(&str) -> std::result::Result<(), String>>,
     pub importer: Option<Arc<dyn Importer>>,
     /// Render Queue encoder (the export layer); `None` = export unavailable.
     pub exporter: Option<Arc<dyn Exporter>>,
@@ -157,6 +186,7 @@ impl Default for Session {
             services: Arc::new(FsServices),
             footage: Arc::new(NoFootage),
             expr: None,
+            expr_check: None,
             importer: None,
             exporter: None,
             render_job: None,
@@ -262,6 +292,7 @@ impl Session {
             self.state.selected_layers.retain(|l| ids.contains(l));
             self.state.selected_props.retain(|(l, _)| ids.contains(l));
             self.state.selected_keys.retain(|k| ids.contains(&k.layer));
+            self.state.selected_vertices.retain(|v| ids.contains(&v.layer));
         }
         self.state.project_selection.retain(|i| p.item(*i).is_some());
     }
@@ -286,7 +317,7 @@ impl Session {
         if let Some(c) = self.state.active_comp {
             let comp = self.project.comp(c);
             let t = match comp {
-                Some(comp) => comp.frame_rate.snap(t.clamp(Tick::ZERO, comp.duration - comp.frame_duration())),
+                Some(comp) => comp.frame_rate.snap_nearest(t.clamp(Tick::ZERO, comp.duration - comp.frame_duration())),
                 None => t,
             };
             self.state.times.insert(c, t);
@@ -306,6 +337,7 @@ impl Session {
             self.state.selected_layers.clear();
             self.state.selected_props.clear();
             self.state.selected_keys.clear();
+            self.state.selected_vertices.clear();
         }
         self.events.push(Event::OpenComp(id));
     }
@@ -372,6 +404,8 @@ impl Session {
 mod rq_tests;
 #[cfg(test)]
 mod tests;
+#[cfg(test)]
+mod tests_timeline;
 
 /// Font families available to text layers (bundled + scanned system fonts).
 pub fn text_families() -> Vec<String> {

crates/engine/src/tests.rs

@@ -205,7 +205,7 @@ fn set_text_paragraph_fill_and_leading() {
 #[test]
 fn prop_get_and_render_rgba8() {
     let mut s = Session::default();
-    s.execute("comp.new", json!({"name": "T", "width": 320, "height": 180, "duration": 2.0})).unwrap();
+    s.execute("comp.new", json!({"name": "T", "width": 320, "height": 180, "duration": 2.0, "frameRate": 30})).unwrap();
     let l = s.execute("layer.newSolid", json!({"color": "#ff0000"})).unwrap()["layer"].as_u64().unwrap();
     s.execute("prop.addKey", json!({"layer": l, "path": "transform/position", "time": 0.0, "value": [0, 0]})).unwrap();
     s.execute("prop.addKey", json!({"layer": l, "path": "transform/position", "time": 1.0, "value": [100, 50]})).unwrap();

crates/engine/src/tests_timeline.rs

@@ -0,0 +1,573 @@
+//! Timeline depth: keyframe clipboard, easing, velocity/interpolation, roving, nudging, graph
+//! editor key edits, time remapping/stretch/reverse/freeze, separate dimensions, pick-whips,
+//! expressions and masks (pen tool). Every command is checked with undo/redo.
+
+use effectcraft_keyframe::{Interp, Value as KV};
+use effectcraft_project::Property;
+use serde_json::{Value, json};
+
+use crate::Session;
+
+/// A 4 s, 30 fps comp with one solid; returns (session, layer id).
+pub(crate) fn setup() -> (Session, u64) {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "T", "width": 400, "height": 300, "frameRate": 30, "duration": 4})).unwrap();
+    let r = s.execute("layer.newSolid", json!({"color": "#ffffff", "width": 100, "height": 100})).unwrap();
+    (s, r["layer"].as_u64().unwrap())
+}
+
+pub(crate) fn prop(s: &Session, layer: u64, path: &str) -> Property {
+    s.active_comp().unwrap().layer(effectcraft_project::LayerId(layer)).unwrap().props.prop(path).unwrap().clone()
+}
+
+/// Key `path` at the given (time, value) pairs.
+pub(crate) fn animate(s: &mut Session, layer: u64, path: &str, keys: &[(f64, Value)]) {
+    for (t, v) in keys {
+        s.execute("prop.addKey", json!({"layer": layer, "path": path, "time": t, "value": v})).unwrap();
+    }
+}
+
+fn select_prop_keys(s: &mut Session, layer: u64, path: &str) {
+    s.execute("prop.select", json!({"layer": layer, "path": path})).unwrap();
+}
+
+fn undo_redo_roundtrip(s: &mut Session, check_after: impl Fn(&Session), check_before: impl Fn(&Session)) {
+    check_after(s);
+    s.execute("edit.undo", json!({})).unwrap();
+    check_before(s);
+    s.execute("edit.redo", json!({})).unwrap();
+    check_after(s);
+}
+
+#[test]
+fn easy_ease_family_sets_influence_and_zero_speed() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/opacity", &[(0.0, json!(0)), (1.0, json!(100)), (2.0, json!(0))]);
+    select_prop_keys(&mut s, l, "transform/opacity");
+    s.execute("keys.easyEase", json!({})).unwrap();
+    undo_redo_roundtrip(
+        &mut s,
+        |s| {
+            let p = prop(s, l, "transform/opacity");
+            assert!(p.keys.iter().all(|k| k.in_interp == Interp::Bezier && k.out_interp == Interp::Bezier));
+            assert!((p.keys[1].in_ease[0].influence - 1.0 / 3.0).abs() < 1e-9 && p.keys[1].in_ease[0].speed == 0.0);
+        },
+        |s| assert!(prop(s, l, "transform/opacity").keys.iter().all(|k| k.in_interp == Interp::Linear)),
+    );
+    // Easy Ease In only touches the incoming side; Out only the outgoing side.
+    s.execute("keys.interpolation", json!({"interpolation": "linear"})).unwrap();
+    s.execute("keys.easyEaseIn", json!({})).unwrap();
+    let p = prop(&s, l, "transform/opacity");
+    assert!(p.keys.iter().all(|k| k.in_interp == Interp::Bezier && k.out_interp == Interp::Linear));
+    s.execute("keys.interpolation", json!({"interpolation": "linear"})).unwrap();
+    s.execute("keys.easyEaseOut", json!({})).unwrap();
+    let p = prop(&s, l, "transform/opacity");
+    assert!(p.keys.iter().all(|k| k.in_interp == Interp::Linear && k.out_interp == Interp::Bezier));
+    // Eased motion is slow near the key.
+    s.execute("keys.easyEase", json!({})).unwrap();
+    let p = prop(&s, l, "transform/opacity");
+    let early = p.value_at(effectcraft_time::Tick::from_seconds_f64(0.1)).as_f64();
+    assert!(early < 5.0, "{early}");
+}
+
+#[test]
+fn keyframe_copy_paste_keeps_relative_timing_and_crosses_properties() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/rotation", &[(0.5, json!(0)), (1.0, json!(90)), (2.0, json!(45))]);
+    select_prop_keys(&mut s, l, "transform/rotation");
+    s.execute("keys.easyEase", json!({})).unwrap();
+    assert_eq!(s.execute("edit.copy", json!({})).unwrap(), json!(3));
+    assert!(s.state.clip_is_keys);
+    // Paste into the same property at 2.5 s: keys at 2.5, 3.0 and 4.0 (clamped by nothing).
+    s.execute("time.set", json!({"time": 2.5})).unwrap();
+    s.execute("keys.select", json!({"keys": []})).unwrap();
+    s.execute("edit.paste", json!({})).unwrap();
+    let after = |s: &Session| {
+        let p = prop(s, l, "transform/rotation");
+        let times: Vec<f64> = p.keys.iter().map(|k| (k.time.seconds() * 30.0).round() / 30.0).collect();
+        assert_eq!(times, vec![0.5, 1.0, 2.0, 2.5, 3.0, 4.0]);
+        assert_eq!(p.keys[4].value, KV::Scalar(90.0));
+        assert_eq!(p.keys[4].in_interp, Interp::Bezier, "interpolation travels with the keys");
+        assert_eq!(s.state.selected_keys.len(), 3, "pasted keys are selected");
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert_eq!(prop(s, l, "transform/rotation").keys.len(), 3));
+    // Cross-property paste of one property's keys into another of the same type (Scalar).
+    let r = s.execute("layer.newSolid", json!({"color": "#ff0000"})).unwrap();
+    let l2 = r["layer"].as_u64().unwrap();
+    select_prop_keys(&mut s, l, "transform/rotation");
+    s.execute("keys.select", json!({"keys": [{"layer": l, "prop": prop(&s, l, "transform/rotation").uid, "time": 1.0}]})).unwrap();
+    s.execute("keys.copy", json!({})).unwrap();
+    s.execute("time.set", json!({"time": 1.0})).unwrap();
+    s.execute("prop.select", json!({"layer": l2, "path": "transform/opacity", "selectKeys": false})).unwrap();
+    s.execute("keys.paste", json!({"layers": [l2]})).unwrap();
+    let op = prop(&s, l2, "transform/opacity");
+    assert_eq!(op.keys.len(), 1);
+    assert_eq!(op.keys[0].value, KV::Scalar(90.0));
+    // Incompatible target (Vec3 position) is refused when explicitly given.
+    let e = s.execute("keys.paste", json!({"layers": [l2], "path": "transform/position"}));
+    assert!(e.is_err() || prop(&s, l2, "transform/position").keys.is_empty());
+}
+
+#[test]
+fn cut_removes_keys_and_paste_restores_them() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/opacity", &[(0.0, json!(10)), (1.0, json!(20))]);
+    select_prop_keys(&mut s, l, "transform/opacity");
+    s.execute("edit.cut", json!({})).unwrap();
+    assert!(prop(&s, l, "transform/opacity").keys.is_empty());
+    s.execute("time.set", json!({"time": 0.0})).unwrap();
+    s.execute("layer.select", json!({"layers": [l]})).unwrap();
+    s.execute("edit.paste", json!({})).unwrap();
+    assert_eq!(prop(&s, l, "transform/opacity").keys.len(), 2);
+}
+
+#[test]
+fn select_all_and_nudge_keys() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/opacity", &[(0.0, json!(10)), (1.0, json!(20))]);
+    animate(&mut s, l, "transform/rotation", &[(0.5, json!(10))]);
+    s.state.selected_props.clear();
+    s.execute("layer.select", json!({"layers": [l]})).unwrap();
+    assert_eq!(s.execute("keys.selectAll", json!({})).unwrap(), json!(3));
+    s.execute("keys.nudgeForward", json!({})).unwrap();
+    let after = |s: &Session| {
+        let p = prop(s, l, "transform/opacity");
+        assert!((p.keys[0].time.seconds() - 1.0 / 30.0).abs() < 1e-6);
+        assert_eq!(s.state.selected_keys.len(), 3);
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert_eq!(prop(s, l, "transform/opacity").keys[0].time.0, 0));
+    s.execute("keys.nudgeBackward10", json!({})).unwrap();
+    let p = prop(&s, l, "transform/opacity");
+    assert!((p.keys[0].time.seconds() + 9.0 / 30.0).abs() < 1e-6, "{}", p.keys[0].time.seconds());
+}
+
+#[test]
+fn velocity_dialog_values_per_dimension_and_continuous() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/scale", &[(0.0, json!([100, 100])), (1.0, json!([200, 50])), (2.0, json!([100, 100]))]);
+    s.execute("keys.select", json!({"keys": [{"layer": l, "prop": prop(&s, l, "transform/scale").uid, "time": 1.0}]})).unwrap();
+    let info = s.execute("keys.info", json!({})).unwrap();
+    assert_eq!(info[0]["units"], "%/sec");
+    assert_eq!(info[0]["dims"], 2);
+    // Linear sides present the segment slope: +100 %/s in X on the incoming side.
+    assert!((info[0]["inEase"][0]["speed"].as_f64().unwrap() - 100.0).abs() < 1e-6, "{info}");
+    s.execute("keys.velocity", json!({"inSpeed": [10, -20], "inInfluence": 50, "continuous": true})).unwrap();
+    let after = |s: &Session| {
+        let k = &prop(s, l, "transform/scale").keys[1];
+        assert_eq!(k.in_ease[0].speed, 10.0);
+        assert_eq!(k.in_ease[1].speed, -20.0);
+        assert_eq!(k.out_ease[1].speed, -20.0, "continuous mirrors incoming");
+        assert!((k.out_ease[0].influence - 0.5).abs() < 1e-9);
+        assert!(k.continuous);
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert_eq!(prop(s, l, "transform/scale").keys[1].in_interp, Interp::Linear));
+}
+
+#[test]
+fn interpolation_dialog_temporal_spatial_and_roving() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/position", &[(0.0, json!([0, 0])), (0.3, json!([300, 0])), (2.0, json!([400, 0]))]);
+    select_prop_keys(&mut s, l, "transform/position");
+    s.execute("keys.interpolation", json!({"interpolation": "hold"})).unwrap();
+    assert!(prop(&s, l, "transform/position").keys.iter().all(|k| k.out_interp == Interp::Hold));
+    s.execute("keys.interpolation", json!({"interpolation": "autoBezier"})).unwrap();
+    assert!(prop(&s, l, "transform/position").keys.iter().all(|k| k.auto_bezier));
+    s.execute("keys.interpolation", json!({"interpolation": "continuousBezier", "spatial": "linear"})).unwrap();
+    let p = prop(&s, l, "transform/position");
+    assert!(p.keys.iter().all(|k| k.continuous && !k.auto_bezier && !k.spatial_auto && k.spatial_out == [0.0; 3]));
+    // Rove the middle key: its time follows the path length (300 of 400 px → 1.5 s).
+    let uid = p.uid;
+    s.execute("keys.select", json!({"keys": [{"layer": l, "prop": uid, "time": 0.3}]})).unwrap();
+    s.execute("keys.interpolation", json!({"roving": true})).unwrap();
+    let after = |s: &Session| {
+        let p = prop(s, l, "transform/position");
+        assert!(p.keys[1].roving);
+        assert!((p.keys[1].time.seconds() - 1.5).abs() < 0.01, "{}", p.keys[1].time.seconds());
+        // The selection follows the roving key.
+        assert!((s.state.selected_keys[0].time.seconds() - 1.5).abs() < 0.01);
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert!(!prop(s, l, "transform/position").keys[1].roving));
+    // Moving the last key re-times the roving key.
+    s.execute("keys.set", json!({"layer": l, "path": "transform/position", "time": 2.0, "newTime": 4.0})).unwrap();
+    let p = prop(&s, l, "transform/position");
+    assert!((p.keys[1].time.seconds() - 3.0).abs() < 0.02, "{}", p.keys[1].time.seconds());
+    // Toggle hold on a key and back.
+    s.execute("keys.select", json!({"keys": [{"layer": l, "prop": uid, "time": 0.0}]})).unwrap();
+    s.execute("keys.toggleHold", json!({})).unwrap();
+    assert_eq!(prop(&s, l, "transform/position").keys[0].out_interp, Interp::Hold);
+    s.execute("keys.toggleHold", json!({})).unwrap();
+    assert_ne!(prop(&s, l, "transform/position").keys[0].out_interp, Interp::Hold);
+}
+
+#[test]
+fn graph_editor_key_and_handle_edits() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/opacity", &[(0.0, json!(0)), (2.0, json!(100))]);
+    // Drag a key in the value graph: new time + value, merged into one undo step.
+    s.execute("keys.set", json!({"layer": l, "path": "transform/opacity", "time": 2.0, "newTime": 1.0, "value": 50, "merge": "g1"})).unwrap();
+    s.execute("keys.set", json!({"layer": l, "path": "transform/opacity", "time": 1.0, "newTime": 1.5, "value": 60, "merge": "g1"})).unwrap();
+    let p = prop(&s, l, "transform/opacity");
+    assert!((p.keys[1].time.seconds() - 1.5).abs() < 1e-6);
+    assert_eq!(p.keys[1].value, KV::Scalar(60.0));
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!((prop(&s, l, "transform/opacity").keys[1].time.seconds() - 2.0).abs() < 1e-6);
+    s.execute("edit.redo", json!({})).unwrap();
+    // A key can't be dragged past its neighbour.
+    s.execute("keys.set", json!({"layer": l, "path": "transform/opacity", "time": 1.5, "newTime": -1.0})).unwrap();
+    let p = prop(&s, l, "transform/opacity");
+    assert!(p.keys[1].time > p.keys[0].time);
+    // Handle drag: out side of key 0 → speed 200 %/s, 60 % influence.
+    s.execute("keys.setEase", json!({"layer": l, "path": "transform/opacity", "time": 0.0, "side": "out", "speed": 200, "influence": 60})).unwrap();
+    let k = &prop(&s, l, "transform/opacity").keys[0];
+    assert_eq!(k.out_interp, Interp::Bezier);
+    assert_eq!(k.out_ease[0].speed, 200.0);
+    assert!((k.out_ease[0].influence - 0.6).abs() < 1e-9);
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(prop(&s, l, "transform/opacity").keys[0].out_interp, Interp::Linear);
+}
+
+#[test]
+fn time_reverse_keyframes() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/opacity", &[(0.0, json!(0)), (1.0, json!(30)), (3.0, json!(100))]);
+    select_prop_keys(&mut s, l, "transform/opacity");
+    s.execute("keys.timeReverse", json!({})).unwrap();
+    let after = |s: &Session| {
+        let p = prop(s, l, "transform/opacity");
+        assert_eq!(p.keys[0].value, KV::Scalar(100.0));
+        assert!((p.keys[1].time.seconds() - 2.0).abs() < 1e-6);
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert_eq!(prop(s, l, "transform/opacity").keys[0].value, KV::Scalar(0.0)));
+}
+
+#[test]
+fn pen_tool_draws_edits_and_closes_a_mask() {
+    let (mut s, l) = setup();
+    // Click (corner), click, drag (Bezier), click on the first vertex (close).
+    let r = s.execute("mask.new", json!({"layer": l, "vertices": [[10, 10]]})).unwrap();
+    let m = r["mask"].as_u64().unwrap();
+    s.execute("mask.addVertex", json!({"layer": l, "mask": m, "point": [90, 10]})).unwrap();
+    s.execute("mask.addVertex", json!({"layer": l, "mask": m, "point": [90, 90]})).unwrap();
+    s.execute("mask.setVertex", json!({"layer": l, "mask": m, "index": 2, "in": [0, -20], "out": [0, 20], "merge": "pen"})).unwrap();
+    s.execute("mask.addVertex", json!({"layer": l, "mask": m, "point": [10, 90]})).unwrap();
+    s.execute("mask.setClosed", json!({"layer": l, "mask": m, "closed": true})).unwrap();
+    let path = |s: &Session| prop(s, l, "masks/#1/path").value.as_path().unwrap().clone();
+    let p = path(&s);
+    assert_eq!(p.vertices, vec![[10.0, 10.0], [90.0, 10.0], [90.0, 90.0], [10.0, 90.0]]);
+    assert_eq!(p.out_tangents[2], [0.0, 20.0]);
+    assert!(p.closed);
+    assert_eq!(s.state.selected_vertices.last().unwrap().index, 3);
+    // The mask cuts the 100×100 solid (layer centred in the 400×300 comp at 150..250, 100..200).
+    let cid = s.active_comp_id().unwrap();
+    let img = s.render(cid, effectcraft_time::Tick::ZERO, effectcraft_render::RenderOpts { scale: 1.0, ..Default::default() });
+    assert!(img.get(200, 150)[3] > 0.99 && img.get(152, 102)[3] < 0.01);
+    // Undo removes the close, redo restores it.
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(!path(&s).closed);
+    s.execute("edit.redo", json!({})).unwrap();
+    // Select two vertices and drag them; Delete removes them.
+    s.execute("mask.selectVertices", json!({"vertices": [{"layer": l, "mask": m, "index": 0}, {"layer": l, "mask": m, "index": 1}]})).unwrap();
+    s.execute("mask.moveVertices", json!({"delta": [5, -5], "merge": "v1"})).unwrap();
+    s.execute("mask.moveVertices", json!({"delta": [5, -5], "merge": "v1"})).unwrap();
+    assert_eq!(path(&s).vertices[1], [100.0, 0.0]);
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(path(&s).vertices[1], [90.0, 10.0], "a drag is one undo step");
+    s.execute("edit.clear", json!({})).unwrap();
+    assert_eq!(path(&s).vertices.len(), 2);
+    assert!(!path(&s).closed);
+    // Animated mask paths get a key at the current time.
+    s.execute("prop.toggleAnimation", json!({"layer": l, "path": "masks/#1/path"})).unwrap();
+    s.execute("time.set", json!({"time": 1.0})).unwrap();
+    s.execute("mask.setVertex", json!({"layer": l, "mask": 1, "index": 0, "point": [0, 0]})).unwrap();
+    assert_eq!(prop(&s, l, "masks/#1/path").keys.len(), 2);
+    // Mode / feather / opacity / expansion through the timeline commands.
+    s.execute("layer.setMask", json!({"layer": l, "mask": m, "mode": "Subtract", "inverted": true})).unwrap();
+    s.execute("prop.set", json!({"layer": l, "path": "masks/#1/feather", "value": [4, 4]})).unwrap();
+    s.execute("prop.set", json!({"layer": l, "path": "masks/#1/expansion", "value": 3})).unwrap();
+    s.execute("prop.set", json!({"layer": l, "path": "masks/#1/opacity", "value": 50})).unwrap();
+    assert_eq!(prop(&s, l, "masks/#1/opacity").value, KV::Scalar(50.0));
+    s.execute("mask.removeAll", json!({"layer": l})).unwrap();
+    assert!(s.active_comp().unwrap().layers[0].masks().unwrap().children.is_empty());
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(s.active_comp().unwrap().layers[0].masks().unwrap().children.len(), 1);
+}
+
+#[test]
+fn alt_click_stopwatch_toggles_a_self_reference_expression() {
+    let (mut s, l) = setup();
+    s.execute("prop.setExpression", json!({"layer": l, "path": "transform/opacity"})).unwrap();
+    assert_eq!(prop(&s, l, "transform/opacity").expr.unwrap().text, "transform.opacity");
+    s.execute("prop.setExpression", json!({"layer": l, "path": "transform/opacity", "enabled": false})).unwrap();
+    assert!(!prop(&s, l, "transform/opacity").expr.unwrap().enabled);
+    s.execute("prop.setExpression", json!({"layer": l, "path": "transform/opacity", "enabled": true})).unwrap();
+    s.execute("prop.setExpression", json!({"layer": l, "path": "transform/opacity"})).unwrap();
+    assert!(prop(&s, l, "transform/opacity").expr.is_none());
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(prop(&s, l, "transform/opacity").expr.unwrap().enabled);
+}
+
+#[test]
+fn layer_comp_and_key_times_stay_frame_aligned() {
+    let aligned = |fr: effectcraft_time::FrameRate, t: effectcraft_time::Tick| fr.snap(t) == t;
+    // The demo project: every comp duration, layer in/out/start and key time is on a frame.
+    let mut s = Session::default();
+    s.execute("file.openDemoProject", json!({})).unwrap();
+    for (_, c) in s.project.comps() {
+        let fr = c.frame_rate;
+        assert!(aligned(fr, c.duration), "duration {:?}", c.duration);
+        for l in &c.layers {
+            for t in [l.in_point, l.out_point, l.start_time] {
+                assert!(aligned(fr, t), "{} {t:?}", l.name);
+            }
+            l.props.walk("", &mut |_, pr| {
+                for k in &pr.keys {
+                    assert!(aligned(fr, l.comp_time(k.time)), "{} {}", l.name, pr.name);
+                }
+            });
+        }
+    }
+    let lower = s.active_comp().unwrap().layer_by_name("Lower Third").unwrap();
+    let fr = s.active_comp().unwrap().frame_rate;
+    assert_eq!(fr.frame_at(lower.in_point), 150, "5 s at 29.97 is frame 150 (0:00:05:00)");
+    // Commands snap: comp duration, layer timing, key times.
+    s.execute("comp.new", json!({"name": "F", "frameRate": 29.97, "duration": 10.0})).unwrap();
+    let c = s.active_comp().unwrap();
+    assert_eq!(c.frame_rate.frame_at(c.duration), 300);
+    assert!(aligned(c.frame_rate, c.duration));
+    let l = s.execute("layer.newSolid", json!({"color": "#fff"})).unwrap()["layer"].as_u64().unwrap();
+    s.execute("layer.timing", json!({"layers": [l], "in": 1.01, "out": 3.3333, "delta": 0.02})).unwrap();
+    let ly = s.active_comp().unwrap().layers[0].clone();
+    let fr = s.active_comp().unwrap().frame_rate;
+    for t in [ly.in_point, ly.out_point, ly.start_time] {
+        assert!(aligned(fr, t), "{t:?}");
+    }
+    s.execute("prop.addKey", json!({"layer": l, "path": "transform/opacity", "time": 1.2345, "value": 10})).unwrap();
+    let k = prop(&s, l, "transform/opacity").keys[0].time;
+    assert!(aligned(fr, ly.comp_time(k)));
+    // Layer shifted one frame (delta 0.02 s rounds to 1 frame): 1.2345 s + 1 frame -> frame 38.
+    assert_eq!(fr.frame_at(ly.comp_time(k)), 38);
+}
+
+#[test]
+fn time_set_snaps_to_the_nearest_frame_and_ae_timecode() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "T", "width": 100, "height": 100, "frameRate": 29.97, "duration": 10})).unwrap();
+    let r = s.execute("time.set", json!({"time": 2.5})).unwrap();
+    assert_eq!(r["frame"], 75);
+    let fr = s.active_comp().unwrap().frame_rate;
+    assert_eq!(effectcraft_time::format_timecode_ae(75, fr, false), "0:00:02:15");
+    assert_eq!(effectcraft_time::format_timecode_ae(75, fr, true), "0;00;02;15");
+}
+
+#[test]
+fn separate_dimensions_split_and_rejoin() {
+    let (mut s, l) = setup();
+    animate(&mut s, l, "transform/position", &[(0.0, json!([0, 100])), (2.0, json!([200, 50]))]);
+    s.execute("prop.separateDimensions", json!({"layer": l})).unwrap();
+    let after = |s: &Session| {
+        let x = prop(s, l, "transform/positionX");
+        let y = prop(s, l, "transform/positionY");
+        assert_eq!(x.keys.len(), 2);
+        assert_eq!(y.keys[1].value, KV::Scalar(50.0));
+        // The layer still renders at the same place (render sees the separated values).
+        let cid = s.active_comp_id().unwrap();
+        let comp = s.project.comp(cid).unwrap();
+        let layer = &comp.layers[0];
+        let ctx = effectcraft_render::EvalCtx::new(&s.project, cid, comp, effectcraft_time::Tick::from_seconds_f64(1.0));
+        let p = ctx.value(layer, layer.transform().unwrap().get("position").unwrap()).as_vec3();
+        assert!((p[0] - 100.0).abs() < 1e-6 && (p[1] - 75.0).abs() < 1e-6, "{p:?}");
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert!(s.active_comp().unwrap().layers[0].transform().unwrap().get("positionX").is_none()));
+    // X and Y animate independently.
+    s.execute("keys.select", json!({"keys": []})).unwrap();
+    s.execute("prop.select", json!({"layer": l, "path": "transform/positionX"})).unwrap();
+    s.execute("keys.easyEase", json!({})).unwrap();
+    assert_eq!(prop(&s, l, "transform/positionY").keys[0].out_interp, Interp::Linear);
+    // Setting Position (viewer drags) writes X/Y.
+    s.execute("time.set", json!({"time": 3.0})).unwrap();
+    s.execute("prop.set", json!({"layer": l, "path": "transform/position", "value": [7, 8, 0]})).unwrap();
+    assert_eq!(prop(&s, l, "transform/positionX").keys.len(), 3);
+    // Re-join: one Position with keys at the union of times.
+    s.execute("prop.separateDimensions", json!({"layer": l})).unwrap();
+    let p = prop(&s, l, "transform/position");
+    assert_eq!(p.keys.len(), 3);
+    assert_eq!(p.keys[2].value, KV::Vec3([7.0, 8.0, 0.0]));
+    assert!(s.active_comp().unwrap().layers[0].transform().unwrap().get("positionX").is_none());
+}
+
+#[test]
+fn parenting_keeps_the_layer_in_place() {
+    let (mut s, child) = setup();
+    let r = s.execute("layer.newNull", json!({})).unwrap();
+    let par = r["layer"].as_u64().unwrap();
+    s.execute("prop.set", json!({"layer": par, "path": "transform/position", "value": [300, 200]})).unwrap();
+    s.execute("prop.set", json!({"layer": par, "path": "transform/rotation", "value": 90})).unwrap();
+    s.execute("prop.set", json!({"layer": par, "path": "transform/scale", "value": [200, 200]})).unwrap();
+    s.execute("prop.set", json!({"layer": child, "path": "transform/position", "value": [100, 50]})).unwrap();
+    let world = |s: &Session| {
+        let cid = s.active_comp_id().unwrap();
+        let comp = s.project.comp(cid).unwrap();
+        let l = comp.layer(effectcraft_project::LayerId(child)).unwrap();
+        let ctx = effectcraft_render::EvalCtx::new(&s.project, cid, comp, effectcraft_time::Tick::ZERO);
+        let (m, _) = ctx.layer_to_comp(l);
+        let a = m.apply(effectcraft_geom::vec2(50.0, 50.0));
+        let b = m.apply(effectcraft_geom::vec2(100.0, 50.0));
+        (a, (b.y - a.y).atan2(b.x - a.x).to_degrees(), (b.x - a.x).hypot(b.y - a.y))
+    };
+    let before = world(&s);
+    s.execute("layer.setParent", json!({"layers": [child], "parent": par})).unwrap();
+    let after = world(&s);
+    assert!((before.0.x - after.0.x).abs() < 1e-6 && (before.0.y - after.0.y).abs() < 1e-6, "{before:?} {after:?}");
+    assert!((before.1 - after.1).abs() < 1e-6 && (before.2 - after.2).abs() < 1e-6);
+    assert!((prop(&s, child, "transform/rotation").value.as_f64() + 90.0).abs() < 1e-9);
+    // Unparenting restores comp-space values.
+    s.execute("layer.setParent", json!({"layers": [child], "parent": null})).unwrap();
+    let p = prop(&s, child, "transform/position").value.as_vec3();
+    assert!((p[0] - 100.0).abs() < 1e-6 && (p[1] - 50.0).abs() < 1e-6, "{p:?}");
+    s.execute("edit.undo", json!({})).unwrap();
+    assert!(s.active_comp().unwrap().layer(effectcraft_project::LayerId(child)).unwrap().parent.is_some());
+}
+
+#[test]
+fn pick_whip_generates_ae_reference_expressions() {
+    let (mut s, l) = setup();
+    let r = s.execute("layer.newSolid", json!({"name": "Other", "color": "#00ff00"})).unwrap();
+    let o = r["layer"].as_u64().unwrap();
+    s.execute("effect.apply", json!({"layer": o, "effect": "Gaussian Blur"})).unwrap();
+    s.execute("layer.addMask", json!({"layer": o})).unwrap();
+    let cases = [
+        ("transform/opacity", json!({"layer": o, "path": "transform/opacity"}), "thisComp.layer(\"Other\").transform.opacity"),
+        ("transform/rotation", json!({"layer": l, "path": "transform/opacity"}), "transform.opacity"),
+        ("transform/rotation", json!({"layer": o, "path": "effects/#1/blurriness"}), "thisComp.layer(\"Other\").effect(\"Gaussian Blur\")(\"Blurriness\")"),
+        ("transform/opacity", json!({"layer": o, "path": "masks/#1/feather"}), "thisComp.layer(\"Other\").mask(\"Mask 1\").maskFeather[0]"),
+        ("transform/scale", json!({"layer": o, "path": "transform/rotation"}), "temp = thisComp.layer(\"Other\").transform.rotation;\n[temp, temp]"),
+        ("transform/position", json!({"layer": o, "path": "transform/position"}), "thisComp.layer(\"Other\").transform.position"),
+    ];
+    for (path, target, want) in cases {
+        let got = s.execute("prop.pickWhip", json!({"layer": l, "path": path, "target": target})).unwrap();
+        assert_eq!(got, json!(want));
+        assert_eq!(prop(&s, l, path).expr.unwrap().text, want);
+    }
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_ne!(prop(&s, l, "transform/position").expr.map(|e| e.text), Some("thisComp.layer(\"Other\").transform.position".into()));
+    assert!(s.execute("prop.pickWhip", json!({"layer": l, "path": "transform/opacity", "target": {"layer": l, "path": "transform/opacity"}})).is_err());
+}
+
+/// Outer comp (4 s) containing a precomp whose 10×10 white solid moves x = 10 + 20·t (t in s).
+/// Returns (session, precomp layer id in the outer comp).
+fn precomp_setup() -> (Session, u64) {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Inner", "width": 100, "height": 100, "frameRate": 30, "duration": 4})).unwrap();
+    let r = s.execute("layer.newSolid", json!({"color": "#ffffff", "width": 10, "height": 10})).unwrap();
+    let l = r["layer"].as_u64().unwrap();
+    animate(&mut s, l, "transform/position", &[(0.0, json!([10, 50])), (4.0, json!([90, 50]))]);
+    s.execute("comp.new", json!({"name": "Outer", "width": 100, "height": 100, "frameRate": 30, "duration": 4})).unwrap();
+    let r = s.execute("layer.addItem", json!({"item": "Inner"})).unwrap();
+    let pl = r["layer"].as_u64().unwrap();
+    s.execute("layer.select", json!({"layers": [pl]})).unwrap();
+    (s, pl)
+}
+
+/// X of the moving square's centre in the outer comp at `t`.
+fn square_x(s: &Session, t: f64) -> f64 {
+    let cid = s.active_comp_id().unwrap();
+    let img = s.render(cid, effectcraft_time::Tick::from_seconds_f64(t), effectcraft_render::RenderOpts { scale: 1.0, ..Default::default() });
+    let xs: Vec<usize> = (0..img.width as usize).filter(|x| img.get(*x as i64, 50)[3] > 0.5).collect();
+    assert!(!xs.is_empty(), "nothing drawn at {t}");
+    (xs[0] + xs[xs.len() - 1]) as f64 / 2.0 + 0.5
+}
+
+#[test]
+fn time_remap_enable_freeze_and_disable() {
+    let (mut s, l) = precomp_setup();
+    assert!((square_x(&s, 1.0) - 30.0).abs() < 1.5);
+    s.execute("layer.enableTimeRemap", json!({})).unwrap();
+    let after = |s: &Session| {
+        let p = prop(s, l, "timeRemap");
+        assert_eq!(p.keys.len(), 2);
+        assert_eq!(p.keys[1].value, KV::Scalar(4.0));
+        // Remapping at identity shows the same frames.
+        assert!((square_x(s, 1.0) - 30.0).abs() < 1.5);
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert!(s.active_comp().unwrap().layers[0].props.get("timeRemap").is_none()));
+    // Remap the first key to show source time 3 s at comp time 0.
+    s.execute("keys.set", json!({"layer": l, "path": "timeRemap", "time": 0.0, "value": 3.0})).unwrap();
+    assert!((square_x(&s, 0.0) - 70.0).abs() < 1.5, "{}", square_x(&s, 0.0));
+    // Freeze Frame at 2 s: one hold key; every frame shows source time 2 s.
+    s.execute("time.set", json!({"time": 2.0})).unwrap();
+    s.execute("keys.set", json!({"layer": l, "path": "timeRemap", "time": 0.0, "value": 0.0})).unwrap();
+    s.execute("layer.freezeFrame", json!({})).unwrap();
+    let p = prop(&s, l, "timeRemap");
+    assert_eq!(p.keys.len(), 1);
+    assert_eq!(p.keys[0].out_interp, Interp::Hold);
+    for t in [0.0, 1.0, 3.5] {
+        assert!((square_x(&s, t) - 50.0).abs() < 1.5, "{t}: {}", square_x(&s, t));
+    }
+    // Ctrl+Alt+T again disables remapping.
+    s.execute("layer.enableTimeRemap", json!({})).unwrap();
+    assert!((square_x(&s, 1.0) - 30.0).abs() < 1.5);
+    // Solids can't be remapped.
+    let r = s.execute("layer.newSolid", json!({"color": "#ff0000"})).unwrap();
+    assert!(s.execute("layer.enableTimeRemap", json!({"layers": [r["layer"]]})).is_err());
+}
+
+#[test]
+fn freeze_on_last_frame_extends_the_layer() {
+    let (mut s, l) = precomp_setup();
+    s.execute("layer.timing", json!({"layers": [l], "out": 2.0})).unwrap();
+    s.execute("layer.freezeOnLastFrame", json!({})).unwrap();
+    let layer = s.active_comp().unwrap().layers[0].clone();
+    assert_eq!(layer.out_point, s.active_comp().unwrap().duration);
+    // Plays normally, then holds the frame before the old out point.
+    assert!((square_x(&s, 1.0) - 30.0).abs() < 1.5);
+    let hold = 10.0 + 20.0 * (2.0 - 1.0 / 30.0);
+    assert!((square_x(&s, 3.5) - hold).abs() < 1.5, "{}", square_x(&s, 3.5));
+}
+
+#[test]
+fn time_reverse_layer_plays_backwards_and_round_trips() {
+    let (mut s, l) = precomp_setup();
+    let before = s.active_comp().unwrap().layers[0].clone();
+    s.execute("layer.timeReverse", json!({})).unwrap();
+    let after = |s: &Session| {
+        let ly = &s.active_comp().unwrap().layers[0];
+        assert_eq!(ly.stretch, -100.0);
+        assert_eq!((ly.in_point, ly.out_point), (before.in_point, before.out_point));
+        // First frame shows the last source frame; the end shows the start.
+        let last = 10.0 + 20.0 * (4.0 - 1.0 / 30.0);
+        assert!((square_x(s, 0.0) - last).abs() < 1.5, "{}", square_x(s, 0.0));
+        assert!((square_x(s, 4.0 - 1.0 / 30.0) - 10.0).abs() < 1.5);
+    };
+    undo_redo_roundtrip(&mut s, after, |s| assert_eq!(s.active_comp().unwrap().layers[0].stretch, 100.0));
+    // Reversing twice restores normal playback.
+    s.execute("layer.timeReverse", json!({"layers": [l]})).unwrap();
+    let ly = &s.active_comp().unwrap().layers[0];
+    assert_eq!(ly.stretch, 100.0);
+    assert_eq!(ly.start_time, before.start_time);
+    assert!((square_x(&s, 1.0) - 30.0).abs() < 1.5);
+}
+
+#[test]
+fn time_stretch_holds_in_current_or_out() {
+    let (mut s, l) = precomp_setup();
+    s.execute("layer.timeStretch", json!({"percent": 50})).unwrap();
+    let ly = s.active_comp().unwrap().layers[0].clone();
+    assert_eq!(ly.stretch, 50.0);
+    assert!((ly.out_point.seconds() - 2.0).abs() < 1e-6);
+    // Twice as fast: comp 1 s shows source 2 s.
+    assert!((square_x(&s, 1.0) - 50.0).abs() < 1.5);
+    s.execute("edit.undo", json!({})).unwrap();
+    // Hold the current frame (2 s) in place while doubling the duration.
+    s.execute("time.set", json!({"time": 2.0})).unwrap();
+    s.execute("layer.timeStretch", json!({"layers": [l], "duration": 8.0, "hold": "current"})).unwrap();
+    let ly = s.active_comp().unwrap().layers[0].clone();
+    assert!((ly.stretch - 200.0).abs() < 1e-6);
+    assert!((ly.in_point.seconds() + 2.0).abs() < 1e-6, "{}", ly.in_point.seconds());
+    assert!((square_x(&s, 2.0) - 50.0).abs() < 1.5);
+    // Hold the out point.
+    s.execute("edit.undo", json!({})).unwrap();
+    s.execute("layer.timeStretch", json!({"layers": [l], "percent": 50, "hold": "out"})).unwrap();
+    let ly = s.active_comp().unwrap().layers[0].clone();
+    assert!((ly.out_point.seconds() - 4.0).abs() < 1e-6 && (ly.in_point.seconds() - 2.0).abs() < 1e-6);
+    assert!(s.execute("layer.timeStretch", json!({"layers": [l], "percent": 0})).is_err());
+}

crates/expr/src/prelude.js

@@ -27,6 +27,9 @@ function __begin(t, v, c, l, path, uid, idx, fd) {
 function __finish(r) {
   r = __v(r);
   if (r !== null && typeof r === 'object' && r.__isLayer) return r.index;
+  // `[temp, temp]` where temp is a property (pick-whip 1D → 2D): read the values here, while
+  // host requests can still be answered and the script re-run.
+  if (Array.isArray(r)) return r.map(function (x) { return __v(x); });
   return r;
 }
 

crates/host/src/lib.rs

@@ -48,6 +48,7 @@ pub fn session() -> Session {
         footage: Arc::new(effectcraft_media::MediaPool::new()),
         importer: Some(Arc::new(MediaImporter)),
         expr: Some(Arc::new(effectcraft_expr::Expressions)),
+        expr_check: Some(effectcraft_expr::check_syntax),
         ..Default::default()
     }
 }
@@ -106,4 +107,61 @@ mod tests {
         s.execute("renderQueue.setRender", json!({"index": 1, "render": true})).unwrap();
         assert_eq!(s.project.render_queue[0].status, effectcraft_engine::project::render_queue::RenderStatus::Queued);
     }
+
+    /// Value of a property of layer `l` at time 0 (keys + expression).
+    fn value(s: &effectcraft_engine::Session, l: u64, path: &str) -> effectcraft_engine::keyframe::Value {
+        let cid = s.active_comp_id().unwrap();
+        let comp = s.project.comp(cid).unwrap();
+        let layer = comp.layer(effectcraft_engine::project::LayerId(l)).unwrap();
+        let ctx = effectcraft_engine::render::EvalCtx { project: &s.project, comp_id: cid, comp, time: Default::default(), expr: s.expr.as_deref() };
+        ctx.value(layer, layer.props.prop(path).unwrap())
+    }
+
+    #[test]
+    fn pick_whip_expressions_evaluate() {
+        let mut s = super::session();
+        s.execute("comp.new", json!({"name": "C", "width": 200, "height": 200, "frameRate": 30, "duration": 2})).unwrap();
+        let a = s.execute("layer.newSolid", json!({"color": "#ffffff"})).unwrap()["layer"].as_u64().unwrap();
+        let b = s.execute("layer.newSolid", json!({"name": "Src", "color": "#ff0000"})).unwrap()["layer"].as_u64().unwrap();
+        s.execute("prop.set", json!({"layer": b, "path": "transform/rotation", "value": 33})).unwrap();
+        s.execute("prop.set", json!({"layer": b, "path": "transform/position", "value": [12, 34]})).unwrap();
+        s.execute("effect.apply", json!({"layer": b, "effect": "Gaussian Blur"})).unwrap();
+        s.execute("prop.set", json!({"layer": b, "path": "effects/#1/blurriness", "value": 21})).unwrap();
+        s.execute("layer.addMask", json!({"layer": b})).unwrap();
+        s.execute("prop.set", json!({"layer": b, "path": "masks/#1/feather", "value": [7, 7]})).unwrap();
+        let link = |s: &mut effectcraft_engine::Session, from: &str, to: &str| {
+            s.execute("prop.pickWhip", json!({"layer": a, "path": from, "target": {"layer": b, "path": to}})).unwrap();
+        };
+        link(&mut s, "transform/opacity", "transform/rotation");
+        assert_eq!(value(&s, a, "transform/opacity").as_f64(), 33.0);
+        link(&mut s, "transform/scale", "transform/rotation");
+        let cid = s.active_comp_id().unwrap();
+        let ep = effectcraft_expr::eval_property(&s.project, cid, effectcraft_engine::project::LayerId(a), "transform/scale", 0.0);
+        assert!(ep.is_ok(), "{ep:?}");
+        assert_eq!(value(&s, a, "transform/scale").as_vec2(), [33.0, 33.0]);
+        link(&mut s, "transform/position", "transform/position");
+        assert_eq!(value(&s, a, "transform/position").as_vec2(), [12.0, 34.0]);
+        link(&mut s, "transform/rotation", "effects/#1/blurriness");
+        assert_eq!(value(&s, a, "transform/rotation").as_f64(), 21.0);
+        link(&mut s, "transform/opacity", "masks/#1/feather");
+        assert_eq!(value(&s, a, "transform/opacity").as_f64(), 7.0);
+        // Separated dimensions: X Position reference.
+        s.execute("prop.separateDimensions", json!({"layer": b})).unwrap();
+        link(&mut s, "transform/rotation", "transform/positionX");
+        assert_eq!(value(&s, a, "transform/rotation").as_f64(), 12.0);
+    }
+
+    #[test]
+    fn expression_syntax_errors_disable_the_expression() {
+        let mut s = super::session();
+        s.execute("comp.new", json!({"name": "C", "width": 100, "height": 100, "frameRate": 30, "duration": 2})).unwrap();
+        let a = s.execute("layer.newSolid", json!({"color": "#ffffff"})).unwrap()["layer"].as_u64().unwrap();
+        let r = s.execute("prop.setExpression", json!({"layer": a, "path": "transform/opacity", "expression": "1 +* ("})).unwrap();
+        assert!(r["error"].is_string(), "{r}");
+        let pr = s.active_comp().unwrap().layers[0].props.prop("transform/opacity").unwrap().clone();
+        assert!(!pr.expr.unwrap().enabled);
+        assert_eq!(value(&s, a, "transform/opacity").as_f64(), 100.0);
+        s.execute("prop.setExpression", json!({"layer": a, "path": "transform/opacity", "expression": "50"})).unwrap();
+        assert_eq!(value(&s, a, "transform/opacity").as_f64(), 50.0);
+    }
 }

crates/keyframe/src/lib.rs

@@ -302,6 +302,110 @@ fn effective_ease(keys: &[Keyframe], i: usize, d: usize, spatial: bool, out: boo
     list.get(d).or(list.first()).copied().unwrap_or_default()
 }
 
+/// The ease a key side presents in the Graph Editor and the Keyframe Velocity dialog: stored
+/// Bezier eases, auto-Bezier slopes, or the equivalent of a linear side (speed of the straight
+/// segment, 33.3 % influence). `None` for hold sides and sides without a neighbour.
+pub fn side_ease(keys: &[Keyframe], i: usize, d: usize, spatial: bool, out: bool) -> Option<Ease> {
+    let k = keys.get(i)?;
+    let j = if out { i + 1 } else { i.checked_sub(1)? };
+    let n = keys.get(j)?;
+    let interp = if out { k.out_interp } else { k.in_interp };
+    if interp == Interp::Hold || (!out && n.out_interp == Interp::Hold) || !k.value.interpolates() {
+        return None;
+    }
+    let is_spatial = spatial && matches!(k.value, Value::Vec2(_) | Value::Vec3(_));
+    if interp == Interp::Linear {
+        let dur = (secs(k.time) - secs(n.time)).abs().max(1e-12);
+        let dv = if is_spatial {
+            let (a, b) = if out { (i, j) } else { (j, i) };
+            spatial_segment_length(keys, a.min(b))
+        } else {
+            let a = k.value.components();
+            let b = n.value.components();
+            let dv = b.get(d).unwrap_or(&0.0) - a.get(d).unwrap_or(&0.0);
+            if out { dv } else { -dv }
+        };
+        return Some(Ease { speed: dv / dur, influence: 1.0 / 3.0 });
+    }
+    Some(effective_ease(keys, i, if is_spatial { 0 } else { d }, is_spatial, out))
+}
+
+/// Arc length of the spatial segment `i` → `i + 1` (motion-path length).
+pub fn spatial_segment_length(keys: &[Keyframe], i: usize) -> f64 {
+    let (Some(a), Some(b)) = (keys.get(i), keys.get(i + 1)) else { return 0.0 };
+    let p0 = v3(&a.value);
+    let p3 = v3(&b.value);
+    let (_, out_t) = spatial_tangents(keys, i);
+    let (in_t, _) = spatial_tangents(keys, i + 1);
+    SpatialSeg::new([p0, [p0[0] + out_t[0], p0[1] + out_t[1], p0[2] + out_t[2]], [p3[0] + in_t[0], p3[1] + in_t[1], p3[2] + in_t[2]], p3]).length()
+}
+
+/// Re-time roving keyframes: each run of roving keys between two fixed (non-roving) keys gets
+/// times proportional to the motion-path length, so the layer moves through them at one
+/// constant speed (After Effects' "Rove Across Time"). The first and last keys never rove.
+/// Returns true when any key time changed. Key order is preserved.
+pub fn retime_roving(keys: &mut [Keyframe], spatial: bool) -> bool {
+    let n = keys.len();
+    if n < 3 {
+        for k in keys.iter_mut() {
+            k.roving = false;
+        }
+        return false;
+    }
+    keys[0].roving = false;
+    keys[n - 1].roving = false;
+    if !keys.iter().any(|k| k.roving) {
+        return false;
+    }
+    let mut changed = false;
+    let mut a = 0;
+    while a < n - 1 {
+        let Some(b) = (a + 1..n).find(|&j| !keys[j].roving) else { break };
+        if b > a + 1 {
+            // Cumulative path length (spatial) or value distance (other) of the run a..=b.
+            let mut acc = vec![0.0];
+            for i in a..b {
+                let len = if spatial && matches!(keys[i].value, Value::Vec2(_) | Value::Vec3(_)) {
+                    spatial_segment_length(keys, i)
+                } else {
+                    let x = keys[i].value.components();
+                    let y = keys[i + 1].value.components();
+                    x.iter().zip(&y).map(|(p, q)| (q - p) * (q - p)).sum::<f64>().sqrt()
+                };
+                acc.push(acc.last().unwrap_or(&0.0) + len);
+            }
+            let total = *acc.last().unwrap_or(&0.0);
+            let (t0, t1) = (keys[a].time, keys[b].time);
+            for (o, i) in (a + 1..b).enumerate() {
+                let f = if total > 1e-9 { acc[o + 1] / total } else { (o + 1) as f64 / (b - a) as f64 };
+                let nt = Tick(t0.0 + ((t1.0 - t0.0) as f64 * f).round() as i64);
+                if nt != keys[i].time {
+                    keys[i].time = nt;
+                    changed = true;
+                }
+                // Roving keys pass speed straight through.
+                keys[i].in_interp = Interp::Linear;
+                keys[i].out_interp = Interp::Linear;
+            }
+        }
+        a = b;
+    }
+    changed
+}
+
+/// Reverse a run of keys in time within `[first, last]` (Time-Reverse Keyframes): key `i` moves
+/// to `first + last - t` and in/out sides swap.
+pub fn time_reverse(keys: &mut [Keyframe]) {
+    let (Some(first), Some(last)) = (keys.first().map(|k| k.time), keys.last().map(|k| k.time)) else { return };
+    for k in keys.iter_mut() {
+        k.time = Tick(first.0 + last.0 - k.time.0);
+        std::mem::swap(&mut k.in_interp, &mut k.out_interp);
+        std::mem::swap(&mut k.in_ease, &mut k.out_ease);
+        std::mem::swap(&mut k.spatial_in, &mut k.spatial_out);
+    }
+    keys.reverse();
+}
+
 /// Evaluate a keyframed property at `t`. `spatial` selects motion-path semantics for 2D/3D values.
 pub fn evaluate(keys: &[Keyframe], t: Tick, spatial: bool) -> Option<Value> {
     let first = keys.first()?;
@@ -524,6 +628,50 @@ mod tests {
         assert_eq!(v.as_path().unwrap().vertices[0], [-7.5, -7.5]);
     }
 
+    #[test]
+    fn roving_keys_get_constant_speed_times() {
+        let mut keys = vec![
+            Keyframe::new(s(0.0), Value::Vec2([0.0, 0.0])),
+            Keyframe::new(s(0.2), Value::Vec2([300.0, 0.0])),
+            Keyframe::new(s(2.0), Value::Vec2([400.0, 0.0])),
+        ];
+        for k in &mut keys {
+            k.spatial_auto = false;
+        }
+        keys[1].roving = true;
+        assert!(retime_roving(&mut keys, true));
+        // 300 of 400 px → 75 % of the 2 s span.
+        assert!((keys[1].time.seconds() - 1.5).abs() < 1e-6, "{}", keys[1].time.seconds());
+        let v0 = speed(&keys, s(0.5), true);
+        let v1 = speed(&keys, s(1.8), true);
+        assert!((v0 - 200.0).abs() < 1.0 && (v1 - 200.0).abs() < 1.0, "{v0} {v1}");
+        // First/last keys can't rove.
+        keys[0].roving = true;
+        retime_roving(&mut keys, true);
+        assert!(!keys[0].roving);
+    }
+
+    #[test]
+    fn side_ease_reports_linear_and_eased_sides() {
+        let keys = vec![Keyframe::new(s(0.0), Value::Scalar(0.0)), Keyframe::new(s(2.0), Value::Scalar(100.0)).eased()];
+        let out = side_ease(&keys, 0, 0, false, true).unwrap();
+        assert!((out.speed - 50.0).abs() < 1e-9);
+        let inn = side_ease(&keys, 1, 0, false, false).unwrap();
+        assert_eq!(inn, Ease::EASY);
+        assert!(side_ease(&keys, 0, 0, false, false).is_none());
+    }
+
+    #[test]
+    fn time_reverse_mirrors_keys() {
+        let mut keys =
+            vec![Keyframe::new(s(1.0), Value::Scalar(0.0)).eased(), Keyframe::new(s(2.0), Value::Scalar(5.0)), Keyframe::new(s(4.0), Value::Scalar(10.0))];
+        keys[0].out_interp = Interp::Hold;
+        time_reverse(&mut keys);
+        assert_eq!(keys.iter().map(|k| k.time.seconds().round() as i64).collect::<Vec<_>>(), vec![1, 3, 4]);
+        assert_eq!(keys[0].value, Value::Scalar(10.0));
+        assert_eq!(keys[2].in_interp, Interp::Hold);
+    }
+
     proptest::proptest! {
         #[test]
         fn eased_values_stay_in_range(t in 0.0f64..1.0, i0 in 0.01f64..1.0, i1 in 0.01f64..1.0) {

crates/keyframe/src/value.rs

@@ -352,6 +352,7 @@ impl Value {
                 }
             }
             Value::Layer(_) => Some(Value::Layer(j.as_u64())),
+            Value::Path(_) => serde_json::from_value::<ShapePath>(j.clone()).ok().map(Value::Path).or_else(|| serde_json::from_value::<Value>(j.clone()).ok()),
             _ => serde_json::from_value::<Value>(j.clone()).ok(),
         }
     }

crates/project/src/props.rs

@@ -399,6 +399,38 @@ impl PropGroup {
         }
         None
     }
+    /// Match-id path (`transform/position`, `effects/ec.blur.gaussian#2/blurriness`) of the node
+    /// with `uid`: portable between layers with the same structure (keyframe paste, pick-whip).
+    pub fn match_path_of(&self, uid: Uid) -> Option<String> {
+        for (i, c) in self.children.iter().enumerate() {
+            let n = self.children[..i].iter().filter(|o| o.match_id() == c.match_id()).count() + 1;
+            let seg = if n == 1 { c.match_id().to_string() } else { format!("{}#{n}", c.match_id()) };
+            if c.uid() == uid {
+                return Some(seg);
+            }
+            if let Node::Group(g) = c
+                && let Some(p) = g.match_path_of(uid)
+            {
+                return Some(format!("{seg}/{p}"));
+            }
+        }
+        None
+    }
+    /// Chain of nodes from this group's children down to `uid` (inclusive).
+    pub fn node_chain(&self, uid: Uid) -> Option<Vec<&Node>> {
+        for c in &self.children {
+            if c.uid() == uid {
+                return Some(vec![c]);
+            }
+            if let Node::Group(g) = c
+                && let Some(mut rest) = g.node_chain(uid)
+            {
+                rest.insert(0, c);
+                return Some(rest);
+            }
+        }
+        None
+    }
     /// Human path (`Transform/Position`) of the node with `uid`.
     pub fn name_path_of(&self, uid: Uid) -> Option<String> {
         for c in &self.children {

crates/render/src/eval.rs

@@ -33,6 +33,16 @@ impl<'a> EvalCtx<'a> {
     }
     /// Value of a property at the context time (keyframes, then expression).
     pub fn value(&self, layer: &Layer, prop: &Property) -> Value {
+        // Separated Position reads as the combination of X/Y/Z Position.
+        if prop.match_id == "position"
+            && let Some(tr) = layer.transform()
+            && let Some(px) = tr.get("positionX")
+            && tr.get("position").is_some_and(|p| p.uid == prop.uid)
+        {
+            let z = tr.get("positionZ").map(|p| self.value(layer, p).as_f64()).unwrap_or(0.0);
+            let y = tr.get("positionY").map(|p| self.value(layer, p).as_f64()).unwrap_or(0.0);
+            return Value::Vec3([self.value(layer, px).as_f64(), y, z]);
+        }
         let lt = layer.layer_time(self.time);
         let v = prop.value_at(lt);
         if prop.has_expression()
@@ -63,6 +73,21 @@ impl<'a> EvalCtx<'a> {
     pub fn b(&self, layer: &Layer, g: &PropGroup, m: &str) -> bool {
         self.group_value(layer, g, m).map(|v| v.as_bool()).unwrap_or(false)
     }
+    /// Layer Position, honouring Separate Dimensions (X/Y/Z Position properties).
+    pub fn position(&self, layer: &Layer, tr: &PropGroup) -> [f64; 3] {
+        match tr.get("positionX") {
+            Some(px) => [self.value(layer, px).as_f64(), self.f(layer, tr, "positionY", 0.0), self.f(layer, tr, "positionZ", 0.0)],
+            None => self.v3(layer, tr, "position", [0.0; 3]),
+        }
+    }
+    /// Source time of a layer at the context time: Time Remap's value when enabled, else the
+    /// (stretch-aware) layer time.
+    pub fn source_time(&self, layer: &Layer) -> Tick {
+        if let Some(tr) = layer.props.get("timeRemap") {
+            return Tick::from_seconds_f64(self.value(layer, tr).as_f64());
+        }
+        layer.layer_time(self.time)
+    }
     pub fn layer(&self, id: LayerId) -> Option<&'a Layer> {
         self.comp.layer(id)
     }
@@ -71,7 +96,7 @@ impl<'a> EvalCtx<'a> {
     pub fn local_matrix(&self, layer: &Layer) -> Mat4 {
         let Some(tr) = layer.transform() else { return Mat4::IDENTITY };
         let three = layer.is_3d();
-        let pos = self.v3(layer, tr, "position", [0.0; 3]);
+        let pos = self.position(layer, tr);
         let rz = self.f(layer, tr, "rotation", 0.0);
         if layer.is_camera() || layer.is_light() {
             return Mat4::translate(Vec3::from(pos)) * Mat4::rotate_z(rz);

crates/render/src/lib.rs

@@ -201,7 +201,7 @@ impl<'a> Renderer<'a> {
                     return None;
                 }
                 let sub = Renderer { depth: self.depth + 1, ..*self };
-                let lt = layer.layer_time(ctx.time);
+                let lt = ctx.source_time(layer);
                 Some(Buf { img: sub.comp_frame(*item, lt), offset: [0.0; 2], scale: s })
             }
             LayerSource::Footage { item } => {
@@ -210,7 +210,7 @@ impl<'a> Renderer<'a> {
                 if !f.has_video {
                     return None;
                 }
-                let lt = layer.layer_time(ctx.time);
+                let lt = ctx.source_time(layer);
                 let img = self.footage.frame(*item, f, lt)?;
                 let k = if img.width > 0 { f.width.max(1) as f64 / img.width as f64 } else { 1.0 };
                 // Keep native pixels when downsampling is small; resample otherwise.
@@ -392,6 +392,8 @@ pub fn render_frame(project: &Project, comp: ItemId, t: Tick, scale: f64) -> Ima
 
 #[cfg(test)]
 mod tests;
+#[cfg(test)]
+mod tests_remap;
 
 /// Layer-space bounds `[x0, y0, x1, y1]` of a layer's content at the context time (source size
 /// for solids/footage/precomps, glyph bounds for text, painted bounds for shapes). Used for viewer

crates/render/src/tests_remap.rs

@@ -0,0 +1,65 @@
+//! Time remapping and separated Position dimensions.
+
+use effectcraft_color::Label;
+use effectcraft_keyframe::{Keyframe, Value};
+use effectcraft_project::build::{self, Ids};
+use effectcraft_project::{Comp, ItemKind, LayerSource, Node, Project, Solid};
+use effectcraft_time::{FrameRate, Tick};
+
+use crate::render_frame;
+
+fn s(x: f64) -> Tick {
+    Tick::from_seconds_f64(x)
+}
+
+#[test]
+fn separated_position_drives_the_transform() {
+    let mut p = Project::default();
+    let comp = Comp::new(200, 100, FrameRate::FPS_30, s(2.0));
+    let cid = p.add_item("Comp", Label::Sandstone, None, ItemKind::Comp(comp.clone().into()));
+    let sid = p.add_item("S", Label::Red, None, ItemKind::Solid(Solid { color: [1.0, 1.0, 1.0], width: 20, height: 20, pixel_aspect: 1.0 }));
+    let mut l = build::layer(&mut p, &comp, "S", LayerSource::Solid { item: sid }, (20, 20), None);
+    let mut next = p.next_id;
+    let mut ids = Ids(&mut next);
+    let mut px = ids.prop("positionX", "X Position", Value::Scalar(20.0));
+    px.keys = vec![Keyframe::new(Tick::ZERO, Value::Scalar(20.0)), Keyframe::new(s(1.0), Value::Scalar(180.0))];
+    let py = ids.prop("positionY", "Y Position", Value::Scalar(50.0));
+    let pz = ids.prop("positionZ", "Z Position", Value::Scalar(0.0));
+    p.next_id = next;
+    let tr = l.props.sub_mut("transform").unwrap();
+    // The combined property is ignored while separated.
+    tr.get_mut("position").unwrap().value = Value::Vec3([100.0, 10.0, 0.0]);
+    tr.children.extend([Node::Prop(px), Node::Prop(py), Node::Prop(pz)]);
+    p.comp_mut(cid).unwrap().layers.push(l);
+    let a = render_frame(&p, cid, Tick::ZERO, 1.0);
+    assert!(a.get(20, 50)[3] > 0.99 && a.get(100, 10)[3] < 0.01);
+    let b = render_frame(&p, cid, s(0.5), 1.0);
+    assert!(b.get(100, 50)[3] > 0.99 && b.get(20, 50)[3] < 0.01);
+}
+
+#[test]
+fn time_remap_picks_the_source_frame() {
+    let mut p = Project::default();
+    let outer = Comp::new(100, 100, FrameRate::FPS_30, s(4.0));
+    let mut inner = Comp::new(100, 100, FrameRate::FPS_30, s(4.0));
+    // Inner comp: a solid that moves from x=10 (t=0) to x=90 (t=2).
+    let sid = p.add_item("S", Label::Red, None, ItemKind::Solid(Solid { color: [1.0, 1.0, 1.0], width: 10, height: 10, pixel_aspect: 1.0 }));
+    let mut l = build::layer(&mut p, &inner, "S", LayerSource::Solid { item: sid }, (10, 10), None);
+    l.props.prop_mut("transform/position").unwrap().keys =
+        vec![Keyframe::new(Tick::ZERO, Value::Vec3([10.0, 50.0, 0.0])), Keyframe::new(s(2.0), Value::Vec3([90.0, 50.0, 0.0]))];
+    inner.layers.push(l);
+    let iid = p.add_item("Inner", Label::Sandstone, None, ItemKind::Comp(inner.into()));
+    let cid = p.add_item("Outer", Label::Sandstone, None, ItemKind::Comp(outer.clone().into()));
+    let mut pre = build::layer(&mut p, &outer, "Inner", LayerSource::Comp { item: iid }, (100, 100), None);
+    let mut next = p.next_id;
+    // Freeze on source time 2 s.
+    let tr = Ids(&mut next).prop("timeRemap", "Time Remap", Value::Scalar(2.0));
+    p.next_id = next;
+    let mut tr = tr;
+    tr.keys = vec![Keyframe::new(Tick::ZERO, Value::Scalar(2.0)).hold()];
+    pre.props.children.push(Node::Prop(tr));
+    p.comp_mut(cid).unwrap().layers.push(pre);
+    let img = render_frame(&p, cid, Tick::ZERO, 1.0);
+    assert!(img.get(90, 50)[3] > 0.99, "frozen at the end position");
+    assert!(img.get(10, 50)[3] < 0.01);
+}

crates/time/src/lib.rs

@@ -330,6 +330,16 @@ pub fn format_timecode_frames(frame: i64, rate: FrameRate, drop_frame: bool) ->
     format!("{}{h:02}{sep}{m:02}{sep}{s:02}{sep}{f:0fw$}", if neg { "-" } else { "" })
 }
 
+/// Format a frame count the way After Effects displays the current time: hours not padded
+/// (`0:00:02:15`, or `0;00;02;15` for drop-frame).
+pub fn format_timecode_ae(frame: i64, rate: FrameRate, drop_frame: bool) -> String {
+    let df = drop_frame && rate.supports_drop_frame();
+    let (neg, h, m, s, f) = frames_to_fields(frame, rate, df);
+    let sep = if df { ';' } else { ':' };
+    let fw = if rate.timecode_base() >= 100 { 3 } else { 2 };
+    format!("{}{h}{sep}{m:02}{sep}{s:02}{sep}{f:0fw$}", if neg { "-" } else { "" })
+}
+
 /// Format a tick according to a display mode.
 pub fn format_time(t: Tick, rate: FrameRate, drop_frame: bool, display: TimeDisplay, sample_rate: i64) -> String {
     let frame = rate.frame_at(t);

crates/ui-egui/src/lib.rs

@@ -41,6 +41,9 @@ pub enum Dialog {
     CompSettings,
     SolidSettings,
     CommandPalette,
+    KeyVelocity,
+    KeyInterpolation,
+    TimeStretch,
 }
 
 /// Host hooks provided by the native app (file pickers etc.).

crates/ui-egui/src/menus.rs

@@ -245,6 +245,9 @@ pub fn invoke(app: &mut EffectcraftApp, ctx: &egui::Context, id: &str, params: V
         "app.compSettings" | "comp.settings" if params.as_object().is_none_or(|m| m.is_empty()) => {
             crate::panels::dialogs::open_comp_settings(app)?;
         }
+        "keys.velocity" if params.as_object().is_none_or(|m| m.is_empty()) => crate::panels::key_dialogs::open_velocity(app)?,
+        "keys.interpolation" if params.as_object().is_none_or(|m| m.is_empty()) => crate::panels::key_dialogs::open_interpolation(app)?,
+        "layer.timeStretch" if params.as_object().is_none_or(|m| m.is_empty()) => crate::panels::key_dialogs::open_time_stretch(app)?,
         "app.solidSettings" | "layer.newSolid" if params.as_object().is_none_or(|m| m.is_empty()) => {
             crate::panels::dialogs::open_new_solid(app)?;
         }

crates/ui-egui/src/panels/dialogs.rs

@@ -6,7 +6,7 @@ use serde_json::json;
 
 use crate::icons::{self, Icon};
 use crate::theme::Tokens;
-use crate::{Dialog, EffectcraftApp, widgets};
+use crate::{Dialog, EffectcraftApp};
 
 pub use super::comp_settings::CompDraft;
 
@@ -19,6 +19,9 @@ pub struct DialogState {
     pub solid_size: [u32; 2],
     pub palette_query: String,
     pub palette_sel: usize,
+    pub velocity: super::key_dialogs::VelocityDraft,
+    pub interp: super::key_dialogs::InterpDraft,
+    pub stretch: super::key_dialogs::StretchDraft,
 }
 
 pub fn open_new_comp(app: &mut EffectcraftApp) {
@@ -63,7 +66,7 @@ pub fn open_new_solid(app: &mut EffectcraftApp) -> Result<(), String> {
     Ok(())
 }
 
-fn modal(ctx: &egui::Context, title: &str, size: egui::Vec2, t: &Tokens, body: impl FnOnce(&mut egui::Ui)) {
+pub(crate) fn modal(ctx: &egui::Context, title: &str, size: egui::Vec2, t: &Tokens, body: impl FnOnce(&mut egui::Ui)) {
     // Dim the app.
     let screen = ctx.content_rect();
     ctx.layer_painter(egui::LayerId::new(egui::Order::Middle, egui::Id::new("modal-dim"))).rect_filled(screen, 0.0, Color32::from_black_alpha(120));
@@ -86,6 +89,9 @@ pub fn show(app: &mut EffectcraftApp, ctx: &egui::Context) {
         Dialog::NewComp | Dialog::CompSettings => comp_settings(app, ctx, &t, d == Dialog::CompSettings),
         Dialog::SolidSettings => solid(app, ctx, &t),
         Dialog::CommandPalette => palette(app, ctx, &t),
+        Dialog::KeyVelocity => super::key_dialogs::velocity(app, ctx, &t),
+        Dialog::KeyInterpolation => super::key_dialogs::interpolation(app, ctx, &t),
+        Dialog::TimeStretch => super::key_dialogs::time_stretch(app, ctx, &t),
     }
 }
 
@@ -185,7 +191,7 @@ fn comp_settings(app: &mut EffectcraftApp, ctx: &egui::Context, t: &Tokens, exis
     }
 }
 
-fn ui_enter(ctx: &egui::Context) -> bool {
+pub(crate) fn ui_enter(ctx: &egui::Context) -> bool {
     !ctx.egui_wants_keyboard_input() && ctx.input(|i| i.key_pressed(egui::Key::Enter))
 }
 

crates/ui-egui/src/panels/graph.rs

@@ -0,0 +1,452 @@
+//! The Graph Editor (Timeline ▸ Shift+F3): value graph and speed graph of the selected (or all
+//! animated) properties, keyframes you can drag in time and value, Bezier/influence handles on
+//! selected keys, auto-zoom / fit, and the bottom button bar (graph type, show selected,
+//! auto-zoom, fit, separate dimensions, hold/linear/auto Bezier, Easy Ease family).
+//!
+//! Every edit is an engine command (`keys.set`, `keys.setEase`, `keys.select`, `keys.*`).
+
+use effectcraft_engine::KeyRef;
+use effectcraft_engine::keyframe::{Interp, Value, side_ease};
+use effectcraft_engine::project::{Comp, Layer, LayerId, Property};
+use effectcraft_engine::render::EvalCtx;
+use effectcraft_engine::time::Tick;
+use egui::{Align2, Color32, Pos2, Rect, Sense, Stroke, StrokeKind, pos2, vec2};
+use serde_json::json;
+
+use super::timeline::TMap;
+use crate::EffectcraftApp;
+use crate::theme::Tokens;
+
+type Actions = Vec<(String, serde_json::Value)>;
+
+const DIM_COLORS: [Color32; 4] =
+    [Color32::from_rgb(0xe0, 0x55, 0x55), Color32::from_rgb(0x5c, 0xc8, 0x5c), Color32::from_rgb(0x50, 0x8c, 0xf0), Color32::from_rgb(0xe8, 0xc8, 0x40)];
+const PROP_COLORS: [Color32; 6] = [
+    Color32::from_rgb(0xe8, 0xc8, 0x40),
+    Color32::from_rgb(0xd0, 0x70, 0xe0),
+    Color32::from_rgb(0x40, 0xc8, 0xc8),
+    Color32::from_rgb(0xf0, 0x90, 0x40),
+    Color32::from_rgb(0x9c, 0xd8, 0x50),
+    Color32::from_rgb(0xf0, 0x70, 0x90),
+];
+
+struct Handle {
+    out: bool,
+    /// Comp seconds / graph value of the handle end.
+    t: f64,
+    v: f64,
+    /// Original speed (sign is kept when dragging in the speed graph).
+    speed: f64,
+    /// Segment duration (layer seconds) the influence is relative to.
+    dur: f64,
+}
+
+struct KeyPt {
+    idx: usize,
+    time: Tick,
+    /// Comp seconds.
+    t: f64,
+    v: f64,
+    sel: bool,
+    handles: Vec<Handle>,
+}
+
+struct Curve<'a> {
+    layer: &'a Layer,
+    prop: &'a Property,
+    dim: usize,
+    color: Color32,
+    pts: Vec<(f64, f64)>,
+    keys: Vec<KeyPt>,
+    /// Values editable in the value graph (not spatial / combined dimensions).
+    editable: bool,
+}
+
+/// Properties shown: the selected ones, or every animated property of the selected layers.
+fn shown_props(app: &EffectcraftApp, comp: &Comp) -> Vec<(LayerId, u64)> {
+    let st = &app.session.state;
+    let numeric = |pr: &Property| !pr.value.components().is_empty() && pr.value.interpolates();
+    if app.ui.timeline.graph_show_selected && !st.selected_props.is_empty() {
+        return st.selected_props.iter().filter(|(l, u)| comp.layer(*l).and_then(|l| l.props.find(*u)).is_some_and(numeric)).copied().collect();
+    }
+    let mut v = vec![];
+    for l in comp.layers.iter().filter(|l| st.selected_layers.contains(&l.id)) {
+        l.props.walk("", &mut |_, pr| {
+            if (pr.is_animated() || pr.has_expression()) && numeric(pr) {
+                v.push((l.id, pr.uid));
+            }
+        });
+    }
+    v
+}
+
+fn shown_dims(l: &Layer, pr: &Property) -> usize {
+    let n = pr.value.components().len();
+    if pr.shown_dims > 0 && !l.is_3d() { (pr.shown_dims as usize).min(n) } else { n.min(4) }
+}
+
+/// Build the curves for the visible time span.
+fn curves<'a>(app: &EffectcraftApp, comp: &'a Comp, ectx: &EvalCtx, tm: TMap, plot: Rect, speed: bool) -> Vec<Curve<'a>> {
+    let sel = &app.session.state.selected_keys;
+    let n = ((plot.width() / 2.0) as usize).max(2);
+    let mut out = vec![];
+    for (pi, (lid, uid)) in shown_props(app, comp).into_iter().enumerate() {
+        let Some(l) = comp.layer(lid) else { continue };
+        let Some(pr) = l.props.find(uid) else { continue };
+        let spatial = pr.spatial && matches!(pr.value, Value::Vec2(_) | Value::Vec3(_));
+        let dims = if speed && spatial { 1 } else { shown_dims(l, pr) };
+        for d in 0..dims {
+            let color = if dims > 1 { DIM_COLORS[d % 4] } else { PROP_COLORS[pi % PROP_COLORS.len()] };
+            let mut pts = Vec::with_capacity(n);
+            for i in 0..n {
+                let x = plot.min.x + plot.width() * i as f32 / (n - 1) as f32;
+                let ct = tm.t(x);
+                let tt = Tick::from_seconds_f64(ct);
+                let v = if speed {
+                    let lt = l.layer_time(tt);
+                    if spatial {
+                        effectcraft_engine::keyframe::speed(&pr.keys, lt, true)
+                    } else {
+                        effectcraft_engine::keyframe::velocity(&pr.keys, lt, false).get(d).copied().unwrap_or(0.0).abs()
+                    }
+                } else {
+                    ectx.at(tt).value(l, pr).components().get(d).copied().unwrap_or(0.0)
+                };
+                pts.push((ct, v));
+            }
+            let mut keys = vec![];
+            for (i, k) in pr.keys.iter().enumerate() {
+                let ks = sel.contains(&KeyRef { layer: lid, prop: uid, time: k.time });
+                let kt = l.comp_time(k.time).seconds();
+                let ed = if spatial { 0 } else { d };
+                let mut handles = vec![];
+                let mut side_speeds = vec![];
+                for out_side in [false, true] {
+                    let Some(e) = side_ease(&pr.keys, i, ed, pr.spatial, out_side) else { continue };
+                    let j = if out_side { i + 1 } else { i - 1 };
+                    let dur = (pr.keys[j].time.seconds() - k.time.seconds()).abs();
+                    side_speeds.push(e.speed.abs());
+                    let dt = e.influence * dur * if out_side { 1.0 } else { -1.0 };
+                    let (hv, show) = if speed { (e.speed.abs(), true) } else { (k.value.components().get(d).copied().unwrap_or(0.0) + e.speed * dt, !spatial) };
+                    let bezier = if out_side { k.out_interp == Interp::Bezier } else { k.in_interp == Interp::Bezier };
+                    if ks && show && (bezier || speed) {
+                        handles.push(Handle { out: out_side, t: kt + dt, v: hv, speed: e.speed, dur });
+                    }
+                }
+                let v = if speed {
+                    if side_speeds.is_empty() { 0.0 } else { side_speeds.iter().sum::<f64>() / side_speeds.len() as f64 }
+                } else {
+                    k.value.components().get(d).copied().unwrap_or(0.0)
+                };
+                keys.push(KeyPt { idx: i, time: k.time, t: kt, v, sel: ks, handles });
+            }
+            out.push(Curve { layer: l, prop: pr, dim: d, color, pts, keys, editable: !spatial });
+        }
+    }
+    out
+}
+
+fn text_button(app: &mut EffectcraftApp, ui: &mut egui::Ui, p: &egui::Painter, x: &mut f32, y: f32, label: &str, on: bool, id: &str, tip: &str) -> bool {
+    let t = app.tokens;
+    let w = p.layout_no_wrap(label.to_string(), Tokens::ui(11.0), t.text).size().x + 14.0;
+    let r = Rect::from_min_size(pos2(*x, y - 9.0), vec2(w, 18.0));
+    let resp = ui.interact(r, egui::Id::new(("graph-btn", id)), Sense::click()).on_hover_text(tip);
+    p.rect_filled(
+        r,
+        3.0,
+        if on {
+            t.accent.gamma_multiply(0.55)
+        } else if resp.hovered() {
+            t.hover
+        } else {
+            Color32::from_rgb(0x2c, 0x2c, 0x2c)
+        },
+    );
+    p.text(r.center(), Align2::CENTER_CENTER, label, Tokens::ui(11.0), if on { Color32::WHITE } else { t.text });
+    app.auto.add(&format!("timeline.graph.{id}"), r, tip);
+    *x += w + 4.0;
+    resp.clicked()
+}
+
+/// Draw the Graph Editor into `area` (the right side of the Timeline) and queue edits.
+pub(crate) fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, p: &egui::Painter, comp: &Comp, ectx: &EvalCtx, tm: TMap, area: Rect, actions: &mut Actions) {
+    let t = app.tokens;
+    let ctx = ui.ctx().clone();
+    let footer_h = 28.0;
+    let plot = Rect::from_min_max(area.min + vec2(0.0, 6.0), pos2(area.max.x, area.max.y - footer_h));
+    let bar = Rect::from_min_max(pos2(area.min.x, area.max.y - footer_h), area.max);
+    // Background first so keys and handles (added later) sit on top for hit-testing.
+    let bg = ui.interact(plot, egui::Id::new("graph-bg"), Sense::click_and_drag());
+    p.rect_filled(area, 0.0, Color32::from_rgb(0x1d, 0x1d, 0x1d));
+    app.auto.add("timeline.graph", plot, &app.ui.timeline.graph_mode.clone());
+    let speed = app.ui.timeline.graph_mode == "speed";
+    let cs = curves(app, comp, ectx, tm, plot, speed);
+
+    // Vertical range: auto-zoom to the curves + handles, or the stored manual range.
+    let (mut lo, mut hi) = (f64::INFINITY, f64::NEG_INFINITY);
+    for c in &cs {
+        for (_, v) in &c.pts {
+            lo = lo.min(*v);
+            hi = hi.max(*v);
+        }
+        for k in &c.keys {
+            for v in std::iter::once(k.v).chain(k.handles.iter().map(|h| h.v)) {
+                lo = lo.min(v);
+                hi = hi.max(v);
+            }
+        }
+    }
+    if !lo.is_finite() {
+        (lo, hi) = (0.0, 100.0);
+    }
+    if speed {
+        lo = lo.min(0.0);
+    }
+    if (hi - lo).abs() < 1e-9 {
+        hi = lo + 1.0;
+    }
+    let pad = (hi - lo) * 0.08;
+    let auto = (lo - pad, hi + pad);
+    // While a key or handle is being dragged the scale stays put (no feedback loop).
+    let drag_id = egui::Id::new("graph-dragging");
+    let dragging = ctx.data(|d| d.get_temp::<bool>(drag_id)).unwrap_or(false) && ctx.input(|i| i.pointer.any_down());
+    let (lo, hi) = if app.ui.timeline.graph_auto_zoom && !dragging { auto } else { app.ui.timeline.graph_range.unwrap_or(auto) };
+    if app.ui.timeline.graph_auto_zoom && !dragging {
+        app.ui.timeline.graph_range = Some((lo, hi));
+    }
+    let ymap = |v: f64| plot.max.y - ((v - lo) / (hi - lo)) as f32 * plot.height();
+    let vmap = |y: f32| lo + (plot.max.y - y) as f64 / plot.height() as f64 * (hi - lo);
+
+    // Grid + value labels.
+    let pc = p.with_clip_rect(plot);
+    let step = nice_step((hi - lo) / 6.0);
+    let mut gv = (lo / step).ceil() * step;
+    while gv <= hi {
+        let y = ymap(gv);
+        pc.line_segment([pos2(plot.min.x, y), pos2(plot.max.x, y)], Stroke::new(1.0, Color32::from_white_alpha(12)));
+        pc.text(pos2(plot.min.x + 4.0, y - 1.0), Align2::LEFT_BOTTOM, fmt(gv, step), Tokens::ui(10.0), t.text_faint);
+        gv += step;
+    }
+    if cs.is_empty() {
+        p.text(plot.center(), Align2::CENTER_CENTER, "Select animated properties to show them in the Graph Editor", Tokens::ui(12.0), t.text_faint);
+    }
+
+    // Curves.
+    for c in &cs {
+        let pts: Vec<Pos2> = c.pts.iter().map(|(ct, v)| pos2(tm.x(*ct), ymap(*v))).collect();
+        pc.add(egui::Shape::line(pts, Stroke::new(1.5, c.color)));
+    }
+    // Keys and handles.
+    let mut key_screens: Vec<(serde_json::Value, Pos2)> = vec![];
+    let fr = comp.frame_rate;
+    for c in &cs {
+        let (lid, uid, d) = (c.layer.id, c.prop.uid, c.dim);
+        for k in &c.keys {
+            let kp = pos2(tm.x(k.t), ymap(k.v));
+            if !plot.expand(6.0).contains(kp) {
+                continue;
+            }
+            let kjson = json!({"layer": lid.0, "prop": uid, "time": k.time.seconds()});
+            key_screens.push((kjson.clone(), kp));
+            // Handles (selected keys).
+            for h in &k.handles {
+                let hp = pos2(tm.x(h.t), ymap(h.v));
+                pc.line_segment([kp, hp], Stroke::new(1.0, Color32::from_rgb(0xd8, 0xd8, 0x60)));
+                pc.circle_filled(hp, 3.5, Color32::from_rgb(0xd8, 0xd8, 0x60));
+                let side = if h.out { "out" } else { "in" };
+                let hr = Rect::from_center_size(hp, vec2(10.0, 10.0));
+                let hresp = ui.interact(hr, egui::Id::new(("ghandle", uid, d, k.idx, side)), Sense::drag());
+                app.auto.add(&format!("timeline.graph.handle.{uid}.{d}.{}.{side}", k.idx), hr, "Bezier handle");
+                if hresp.dragged()
+                    && let Some(pt) = hresp.interact_pointer_pos()
+                {
+                    ctx.data_mut(|dd| dd.insert_temp(drag_id, true));
+                    let mut dt = (tm.t(pt.x) - k.t) * if h.out { 1.0 } else { -1.0 };
+                    dt = dt.max(h.dur * 0.001);
+                    let influence = (dt / h.dur.max(1e-9) * 100.0).clamp(0.1, 100.0);
+                    let sp = if speed {
+                        let mag = vmap(pt.y).max(0.0);
+                        if h.speed < 0.0 { -mag } else { mag }
+                    } else {
+                        let dv = vmap(pt.y) - k.v;
+                        dv / dt * if h.out { 1.0 } else { -1.0 }
+                    };
+                    let mut params = json!({"layer": lid.0, "prop": uid, "time": k.time.seconds(), "side": side, "speed": sp, "influence": influence, "merge": format!("ghandle-{uid}-{}", k.idx)});
+                    if c.editable {
+                        params["dim"] = json!(d);
+                    }
+                    actions.push(("keys.setEase".into(), params));
+                }
+                if hresp.drag_stopped() {
+                    ctx.data_mut(|dd| dd.insert_temp(drag_id, false));
+                    actions.push(("__endMerge".into(), json!({})));
+                }
+            }
+            // The key itself.
+            let col = if k.sel { t.keyframe_selected } else { Color32::from_gray(0xe0) };
+            pc.rect_filled(Rect::from_center_size(kp, vec2(7.0, 7.0)), 0.0, col);
+            pc.rect_stroke(Rect::from_center_size(kp, vec2(7.0, 7.0)), 0.0, Stroke::new(1.0, c.color), StrokeKind::Outside);
+            let kr = Rect::from_center_size(kp, vec2(11.0, 11.0));
+            let kresp = ui.interact(kr, egui::Id::new(("gkey", uid, d, k.idx)), Sense::click_and_drag());
+            app.auto.add(&format!("timeline.graph.key.{uid}.{d}.{}", k.idx), kr, &c.prop.name);
+            let shift = ui.input(|i| i.modifiers.shift);
+            if (kresp.clicked() || kresp.drag_started()) && (!k.sel || shift) {
+                actions.push(("keys.select".into(), json!({"keys": [kjson.clone()], "add": shift})));
+            }
+            if kresp.dragged()
+                && let Some(pt) = kresp.interact_pointer_pos()
+            {
+                ctx.data_mut(|dd| dd.insert_temp(drag_id, true));
+                let merge = format!("gkey-{uid}-{}", k.idx);
+                let nt = c.layer.layer_time(fr.snap_nearest(Tick::from_seconds_f64(tm.t(pt.x).max(0.0))));
+                let mut params = json!({"layer": lid.0, "prop": uid, "time": k.time.seconds(), "newTime": nt.seconds(), "merge": merge});
+                if !speed && c.editable {
+                    let mut comps = c.prop.keys[k.idx].value.components();
+                    if d < comps.len() {
+                        comps[d] = vmap(pt.y);
+                    }
+                    params["value"] = if comps.len() == 1 { json!(comps[0]) } else { json!(comps) };
+                }
+                actions.push(("keys.set".into(), params));
+            }
+            if kresp.drag_stopped() {
+                ctx.data_mut(|dd| dd.insert_temp(drag_id, false));
+                actions.push(("__endMerge".into(), json!({})));
+            }
+        }
+    }
+
+    // Background: click deselects keys, drag box-selects.
+    if bg.clicked() {
+        actions.push(("keys.select".into(), json!({"keys": []})));
+    }
+    if bg.dragged()
+        && let (Some(o), Some(cur)) = (ctx.input(|i| i.pointer.press_origin()), bg.interact_pointer_pos())
+    {
+        let br = Rect::from_two_pos(o, cur);
+        pc.rect_filled(br, 0.0, t.accent.gamma_multiply(0.12));
+        pc.rect_stroke(br, 0.0, Stroke::new(1.0, t.accent), StrokeKind::Middle);
+        ctx.data_mut(|d| d.insert_temp(egui::Id::new("graph-box"), br));
+    }
+    if bg.drag_stopped()
+        && let Some(br) = ctx.data(|d| d.get_temp::<Rect>(egui::Id::new("graph-box")))
+    {
+        ctx.data_mut(|d| d.remove::<Rect>(egui::Id::new("graph-box")));
+        let keys: Vec<serde_json::Value> = key_screens.iter().filter(|(_, sp)| br.contains(*sp)).map(|(k, _)| k.clone()).collect();
+        actions.push(("keys.select".into(), json!({"keys": keys, "add": ui.input(|i| i.modifiers.shift)})));
+    }
+    // Wheel over the graph with Alt/Ctrl zooms the value axis (turns auto-zoom off).
+    if ui.rect_contains_pointer(plot) {
+        let (dy, zoom) = ui.input(|i| (i.smooth_scroll_delta.y, i.modifiers.ctrl || i.modifiers.command));
+        if zoom && dy.abs() > 0.0 {
+            let k = (-dy as f64 / 200.0).exp();
+            let mid = (lo + hi) / 2.0;
+            app.ui.timeline.graph_auto_zoom = false;
+            app.ui.timeline.graph_range = Some((mid - (mid - lo) * k, mid + (hi - mid) * k));
+        }
+    }
+
+    // Button bar.
+    p.rect_filled(bar, 0.0, t.panel_bg);
+    p.line_segment([bar.left_top(), bar.right_top()], Stroke::new(1.0, t.separator));
+    let y = bar.center().y;
+    let mut x = bar.min.x + 8.0;
+    let tl = &app.ui.timeline;
+    let (is_value, show_sel, auto_on) = (tl.graph_mode != "speed", tl.graph_show_selected, tl.graph_auto_zoom);
+    if text_button(app, ui, p, &mut x, y, "Value", is_value, "valueGraph", "Edit Value Graph") {
+        app.ui.timeline.graph_mode = "value".into();
+    }
+    if text_button(app, ui, p, &mut x, y, "Speed", !is_value, "speedGraph", "Edit Speed Graph") {
+        app.ui.timeline.graph_mode = "speed".into();
+    }
+    x += 6.0;
+    if text_button(app, ui, p, &mut x, y, "Selected", show_sel, "showSelected", "Show Selected Properties (else all animated properties)") {
+        app.ui.timeline.graph_show_selected = !show_sel;
+    }
+    if text_button(app, ui, p, &mut x, y, "Auto-zoom", auto_on, "autoZoom", "Auto-zoom graph height") {
+        app.ui.timeline.graph_auto_zoom = !auto_on;
+    }
+    if text_button(app, ui, p, &mut x, y, "Fit", false, "fit", "Fit all graphs to view") {
+        app.ui.timeline.graph_auto_zoom = true;
+        app.ui.timeline.pps = None;
+    }
+    if text_button(app, ui, p, &mut x, y, "Fit Selection", false, "fitSelection", "Fit selection to view") {
+        fit_selection(app, &cs, tm, plot);
+    }
+    x += 6.0;
+    let pos_sel = app.session.state.selected_props.iter().find_map(|(l, u)| {
+        let layer = comp.layer(*l)?;
+        let tr = layer.transform()?;
+        (tr.get("position").is_some_and(|p| p.uid == *u) || ["positionX", "positionY", "positionZ"].iter().any(|m| tr.get(m).is_some_and(|p| p.uid == *u)))
+            .then_some(l.0)
+    });
+    if text_button(app, ui, p, &mut x, y, "Separate Dimensions", false, "separateDimensions", "Separate Dimensions (Position)")
+        && let Some(l) = pos_sel.or(app.session.state.selected_layers.first().map(|l| l.0))
+    {
+        actions.push(("prop.separateDimensions".into(), json!({"layer": l})));
+    }
+    x += 6.0;
+    for (label, cmd, params, tip) in [
+        ("Hold", "keys.interpolation", json!({"interpolation": "hold"}), "Convert selected keyframes to Hold"),
+        ("Linear", "keys.interpolation", json!({"interpolation": "linear"}), "Convert selected keyframes to Linear"),
+        ("Auto Bezier", "keys.interpolation", json!({"interpolation": "autoBezier"}), "Convert selected keyframes to Auto Bezier"),
+        ("Easy Ease", "keys.easyEase", json!({}), "Easy Ease (F9)"),
+        ("Ease In", "keys.easyEaseIn", json!({}), "Easy Ease In (Shift+F9)"),
+        ("Ease Out", "keys.easyEaseOut", json!({}), "Easy Ease Out (Ctrl+Shift+F9)"),
+    ] {
+        let id = cmd.trim_start_matches("keys.").to_string() + label.split_whitespace().next().unwrap_or("");
+        if text_button(app, ui, p, &mut x, y, label, false, &id, tip) {
+            actions.push((cmd.into(), params));
+        }
+    }
+}
+
+/// Zoom time and value to the selected keys (and their handles).
+fn fit_selection(app: &mut EffectcraftApp, cs: &[Curve], tm: TMap, plot: Rect) {
+    let mut t0 = f64::INFINITY;
+    let mut t1 = f64::NEG_INFINITY;
+    let mut v0 = f64::INFINITY;
+    let mut v1 = f64::NEG_INFINITY;
+    for c in cs {
+        for k in c.keys.iter().filter(|k| k.sel) {
+            for (t, v) in std::iter::once((k.t, k.v)).chain(k.handles.iter().map(|h| (h.t, h.v))) {
+                t0 = t0.min(t);
+                t1 = t1.max(t);
+                v0 = v0.min(v);
+                v1 = v1.max(v);
+            }
+        }
+    }
+    if !t0.is_finite() {
+        return;
+    }
+    let span = (t1 - t0).max(0.2);
+    let pps = (plot.width() as f64 * 0.8 / span).clamp(5.0, 4000.0);
+    app.ui.timeline.pps = Some(pps);
+    app.ui.timeline.start = (t0 - span * 0.1).max(0.0);
+    let pad = ((v1 - v0) * 0.15).max(1.0);
+    app.ui.timeline.graph_auto_zoom = false;
+    app.ui.timeline.graph_range = Some((v0 - pad, v1 + pad));
+    let _ = tm;
+}
+
+fn nice_step(raw: f64) -> f64 {
+    let raw = raw.abs().max(1e-9);
+    let mag = 10f64.powf(raw.log10().floor());
+    let n = raw / mag;
+    mag * if n < 1.5 {
+        1.0
+    } else if n < 3.5 {
+        2.0
+    } else if n < 7.5 {
+        5.0
+    } else {
+        10.0
+    }
+}
+
+fn fmt(v: f64, step: f64) -> String {
+    let dec = if step >= 1.0 { 0 } else { (-step.log10()).ceil() as usize };
+    let s = format!("{v:.dec$}");
+    if s.trim_start_matches('-').chars().all(|c| c == '0' || c == '.') { s.trim_start_matches('-').to_string() } else { s }
+}

crates/ui-egui/src/panels/key_dialogs.rs

@@ -0,0 +1,287 @@
+//! Animation dialogs: Keyframe Velocity, Keyframe Interpolation and Time Stretch. Each one is
+//! pre-filled from the engine (`keys.info`, the layer) and commits through one engine command.
+
+use egui::{Color32, vec2};
+use serde_json::{Value, json};
+
+use crate::theme::Tokens;
+use crate::{Dialog, EffectcraftApp};
+
+#[derive(Clone, Debug, Default)]
+pub struct VelocityDraft {
+    pub dims: usize,
+    pub units: String,
+    pub name: String,
+    pub in_speed: Vec<f64>,
+    pub in_inf: Vec<f64>,
+    pub out_speed: Vec<f64>,
+    pub out_inf: Vec<f64>,
+    /// Which sides exist (first key has no incoming side, last none outgoing).
+    pub has_in: bool,
+    pub has_out: bool,
+    pub continuous: bool,
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct InterpDraft {
+    /// Index into TEMPORAL / SPATIAL / ROVING (0 = Current Settings).
+    pub temporal: usize,
+    pub spatial: usize,
+    pub roving: usize,
+    pub has_spatial: bool,
+    pub count: usize,
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct StretchDraft {
+    pub percent: f64,
+    pub duration: f64,
+    /// 0 = Layer In-point, 1 = Current Frame, 2 = Layer Out-point.
+    pub hold: usize,
+    pub orig_duration: f64,
+    pub orig_percent: f64,
+}
+
+pub const TEMPORAL: [(&str, &str); 6] = [
+    ("Current Settings", ""),
+    ("Linear", "linear"),
+    ("Bezier", "bezier"),
+    ("Continuous Bezier", "continuousBezier"),
+    ("Auto Bezier", "autoBezier"),
+    ("Hold", "hold"),
+];
+pub const SPATIAL: [(&str, &str); 5] =
+    [("Current Settings", ""), ("Linear", "linear"), ("Bezier", "bezier"), ("Continuous Bezier", "continuousBezier"), ("Auto Bezier", "autoBezier")];
+pub const ROVING: [&str; 3] = ["Current Settings", "Lock To Time", "Rove Across Time"];
+
+fn num(v: &Value) -> f64 {
+    v.as_f64().unwrap_or(0.0)
+}
+
+/// Animation ▸ Keyframe Velocity… (⇧⌘K) with keys selected.
+pub fn open_velocity(app: &mut EffectcraftApp) -> Result<(), String> {
+    let info = app.session.execute("keys.info", json!({})).map_err(|e| e.to_string())?;
+    let first = info.as_array().and_then(|a| a.first()).ok_or("select keyframes first")?;
+    let dims = first["dims"].as_u64().unwrap_or(1).max(1) as usize;
+    let side = |k: &str| -> (Vec<f64>, Vec<f64>, bool) {
+        let a = first[k].as_array().cloned().unwrap_or_default();
+        let has = a.iter().any(|e| !e.is_null());
+        let sp = (0..dims).map(|d| a.get(d).map(|e| num(&e["speed"])).unwrap_or(0.0)).collect();
+        let inf = (0..dims).map(|d| a.get(d).map(|e| num(&e["influence"])).filter(|v| *v > 0.0).unwrap_or(33.33)).collect();
+        (sp, inf, has)
+    };
+    let (in_speed, in_inf, has_in) = side("inEase");
+    let (out_speed, out_inf, has_out) = side("outEase");
+    app.dialog_state.velocity = VelocityDraft {
+        dims,
+        units: first["units"].as_str().unwrap_or("units/sec").into(),
+        name: first["name"].as_str().unwrap_or("").into(),
+        in_speed,
+        in_inf,
+        out_speed,
+        out_inf,
+        has_in,
+        has_out,
+        continuous: first["continuous"].as_bool().unwrap_or(false),
+    };
+    app.dialog = Some(Dialog::KeyVelocity);
+    Ok(())
+}
+
+/// Animation ▸ Keyframe Interpolation… (⌥⌘K).
+pub fn open_interpolation(app: &mut EffectcraftApp) -> Result<(), String> {
+    let info = app.session.execute("keys.info", json!({})).map_err(|e| e.to_string())?;
+    let a = info.as_array().cloned().unwrap_or_default();
+    if a.is_empty() {
+        return Err("select keyframes first".into());
+    }
+    app.dialog_state.interp = InterpDraft { has_spatial: a.iter().any(|k| !k["spatial"].is_null()), count: a.len(), ..Default::default() };
+    app.dialog = Some(Dialog::KeyInterpolation);
+    Ok(())
+}
+
+/// Layer ▸ Time ▸ Time Stretch…
+pub fn open_time_stretch(app: &mut EffectcraftApp) -> Result<(), String> {
+    let lid = *app.session.state.selected_layers.first().ok_or("select a layer first")?;
+    let l = app.session.active_comp().and_then(|c| c.layer(lid)).ok_or("no layer")?;
+    let dur = (l.out_point - l.in_point).seconds();
+    app.dialog_state.stretch = StretchDraft { percent: l.stretch, duration: dur, hold: 0, orig_duration: dur, orig_percent: l.stretch };
+    app.dialog = Some(Dialog::TimeStretch);
+    Ok(())
+}
+
+fn buttons(ui: &mut egui::Ui, app: &mut EffectcraftApp, t: &Tokens, prefix: &str) -> (bool, bool) {
+    let (mut ok, mut cancel) = (false, false);
+    ui.add_space(14.0);
+    ui.with_layout(egui::Layout::right_to_left(egui::Align::Center), |ui| {
+        let r = ui.add(egui::Button::new(egui::RichText::new("   OK   ").color(Color32::WHITE)).fill(t.accent));
+        app.auto.add(&format!("{prefix}.ok"), r.rect, "OK");
+        ok = r.clicked();
+        let r = ui.button("Cancel");
+        app.auto.add(&format!("{prefix}.cancel"), r.rect, "Cancel");
+        cancel = r.clicked();
+    });
+    (ok, cancel)
+}
+
+fn drag(ui: &mut egui::Ui, app: &mut EffectcraftApp, id: &str, v: &mut f64, speed: f64, range: std::ops::RangeInclusive<f64>, suffix: &str, enabled: bool) {
+    let r = ui.add_enabled(enabled, egui::DragValue::new(v).speed(speed).range(range).max_decimals(2).suffix(suffix));
+    app.auto.add(id, r.rect, id);
+}
+
+pub fn velocity(app: &mut EffectcraftApp, ctx: &egui::Context, t: &Tokens) {
+    let mut d = app.dialog_state.velocity.clone();
+    let (mut ok, mut cancel) = (false, false);
+    let title = if d.name.is_empty() { "Keyframe Velocity".to_string() } else { format!("Keyframe Velocity: {}", d.name) };
+    let h = 250.0 + 2.0 * 26.0 * d.dims as f32;
+    super::dialogs::modal(ctx, &title, vec2(440.0, h), t, |ui| {
+        for (label, out) in [("Incoming Velocity", false), ("Outgoing Velocity", true)] {
+            ui.label(egui::RichText::new(label).font(Tokens::medium(12.5)));
+            let enabled = if out { d.has_out } else { d.has_in };
+            egui::Grid::new(("vel", out)).num_columns(3).spacing([12.0, 6.0]).show(ui, |ui| {
+                for dim in 0..d.dims {
+                    let tag = if d.dims > 1 { format!("Dimension {}", ["X", "Y", "Z", "W"][dim.min(3)]) } else { String::new() };
+                    ui.label(egui::RichText::new(tag).color(t.text_dim));
+                    let side = if out { "out" } else { "in" };
+                    ui.horizontal(|ui| {
+                        ui.label("Speed:");
+                        let v = if out { &mut d.out_speed[dim] } else { &mut d.in_speed[dim] };
+                        drag(ui, app, &format!("dialog.velocity.{side}Speed.{dim}"), v, 1.0, -1e7..=1e7, "", enabled);
+                        ui.label(egui::RichText::new(&d.units).color(t.text_dim));
+                    });
+                    ui.horizontal(|ui| {
+                        ui.label("Influence:");
+                        let v = if out { &mut d.out_inf[dim] } else { &mut d.in_inf[dim] };
+                        drag(ui, app, &format!("dialog.velocity.{side}Influence.{dim}"), v, 0.2, 0.1..=100.0, " %", enabled);
+                    });
+                    ui.end_row();
+                }
+            });
+            ui.add_space(8.0);
+        }
+        let r = ui.checkbox(&mut d.continuous, "Continuous (Lock Outgoing to Incoming)");
+        app.auto.add("dialog.velocity.continuous", r.rect, "Continuous");
+        if d.continuous {
+            d.out_speed = d.in_speed.clone();
+        }
+        (ok, cancel) = buttons(ui, app, t, "dialog.velocity");
+    });
+    app.dialog_state.velocity = d.clone();
+    if ok || super::dialogs::ui_enter(ctx) {
+        let mut params = json!({"continuous": d.continuous});
+        if d.has_in {
+            params["inSpeed"] = json!(d.in_speed);
+            params["inInfluence"] = json!(d.in_inf);
+        }
+        if d.has_out {
+            params["outSpeed"] = json!(d.out_speed);
+            params["outInfluence"] = json!(d.out_inf);
+        }
+        if let Err(e) = app.session.execute("keys.velocity", params) {
+            app.ui.status = e.to_string();
+        }
+        cancel = true;
+    }
+    if cancel {
+        app.dialog = None;
+    }
+}
+
+fn combo(ui: &mut egui::Ui, app: &mut EffectcraftApp, id: &str, sel: &mut usize, opts: &[&str], enabled: bool) {
+    ui.add_enabled_ui(enabled, |ui| {
+        let r = egui::ComboBox::from_id_salt(id).width(200.0).selected_text(opts[*sel]).show_ui(ui, |ui| {
+            for (i, o) in opts.iter().enumerate() {
+                ui.selectable_value(sel, i, *o);
+            }
+        });
+        app.auto.add(id, r.response.rect, id);
+    });
+}
+
+pub fn interpolation(app: &mut EffectcraftApp, ctx: &egui::Context, t: &Tokens) {
+    let mut d = app.dialog_state.interp.clone();
+    let (mut ok, mut cancel) = (false, false);
+    super::dialogs::modal(ctx, "Keyframe Interpolation", vec2(440.0, 250.0), t, |ui| {
+        egui::Grid::new("interp-grid").num_columns(2).spacing([14.0, 10.0]).show(ui, |ui| {
+            ui.label("Temporal Interpolation:");
+            combo(ui, app, "dialog.interpolation.temporal", &mut d.temporal, &TEMPORAL.map(|x| x.0), true);
+            ui.end_row();
+            ui.label("Spatial Interpolation:");
+            combo(ui, app, "dialog.interpolation.spatial", &mut d.spatial, &SPATIAL.map(|x| x.0), d.has_spatial);
+            ui.end_row();
+            ui.label("Roving:");
+            combo(ui, app, "dialog.interpolation.roving", &mut d.roving, &ROVING, d.has_spatial);
+            ui.end_row();
+        });
+        ui.add_space(6.0);
+        ui.label(egui::RichText::new(format!("{} keyframe{} selected", d.count, if d.count == 1 { "" } else { "s" })).color(t.text_dim));
+        (ok, cancel) = buttons(ui, app, t, "dialog.interpolation");
+    });
+    app.dialog_state.interp = d.clone();
+    if ok || super::dialogs::ui_enter(ctx) {
+        let mut params = json!({});
+        if d.temporal > 0 {
+            params["interpolation"] = json!(TEMPORAL[d.temporal].1);
+        }
+        if d.spatial > 0 && d.has_spatial {
+            params["spatial"] = json!(SPATIAL[d.spatial].1);
+        }
+        if d.roving > 0 && d.has_spatial {
+            params["roving"] = json!(d.roving == 2);
+        }
+        if params.as_object().is_some_and(|m| !m.is_empty())
+            && let Err(e) = app.session.execute("keys.interpolation", params)
+        {
+            app.ui.status = e.to_string();
+        }
+        cancel = true;
+    }
+    if cancel {
+        app.dialog = None;
+    }
+}
+
+pub fn time_stretch(app: &mut EffectcraftApp, ctx: &egui::Context, t: &Tokens) {
+    let mut d = app.dialog_state.stretch.clone();
+    let (mut ok, mut cancel) = (false, false);
+    super::dialogs::modal(ctx, "Time Stretch", vec2(420.0, 300.0), t, |ui| {
+        ui.label(egui::RichText::new("Stretch").font(Tokens::medium(12.5)));
+        egui::Grid::new("stretch-grid").num_columns(2).spacing([14.0, 8.0]).show(ui, |ui| {
+            ui.label("Original Duration:");
+            ui.label(format!("{:.2} s", d.orig_duration));
+            ui.end_row();
+            ui.label("Stretch Factor:");
+            let before = d.percent;
+            drag(ui, app, "dialog.timeStretch.percent", &mut d.percent, 0.5, -10000.0..=10000.0, " %", true);
+            if (before - d.percent).abs() > 1e-9 && d.orig_percent.abs() > 1e-9 {
+                d.duration = d.orig_duration * d.percent.abs() / d.orig_percent.abs();
+            }
+            ui.end_row();
+            ui.label("New Duration:");
+            let before = d.duration;
+            drag(ui, app, "dialog.timeStretch.duration", &mut d.duration, 0.05, 0.01..=100000.0, " s", true);
+            if (before - d.duration).abs() > 1e-9 && d.orig_duration > 1e-9 {
+                d.percent = d.orig_percent.signum() * d.orig_percent.abs() * d.duration / d.orig_duration;
+            }
+            ui.end_row();
+        });
+        ui.add_space(10.0);
+        ui.label(egui::RichText::new("Hold In Place").font(Tokens::medium(12.5)));
+        for (i, l) in ["Layer In-point", "Current Frame", "Layer Out-point"].into_iter().enumerate() {
+            let r = ui.radio_value(&mut d.hold, i, l);
+            app.auto.add(&format!("dialog.timeStretch.hold.{i}"), r.rect, l);
+        }
+        (ok, cancel) = buttons(ui, app, t, "dialog.timeStretch");
+    });
+    app.dialog_state.stretch = d.clone();
+    if ok || super::dialogs::ui_enter(ctx) {
+        let hold = ["in", "current", "out"][d.hold.min(2)];
+        if let Err(e) = app.session.execute("layer.timeStretch", json!({"percent": d.percent, "hold": hold})) {
+            app.ui.status = e.to_string();
+        }
+        cancel = true;
+    }
+    if cancel {
+        app.dialog = None;
+    }
+}

crates/ui-egui/src/panels/mod.rs

@@ -4,7 +4,9 @@ pub mod comp_settings;
 pub mod dialogs;
 pub mod effect_controls;
 pub mod effects_presets;
+pub mod graph;
 pub mod info;
+pub mod key_dialogs;
 pub mod misc;
 pub mod project;
 pub mod properties;
@@ -35,11 +37,8 @@ pub fn timecode(session: &Session, comp: &Comp, t: Tick) -> String {
     let fr = comp.frame_rate;
     match session.project.settings.time_display {
         TimeDisplayStyle::Frames => format!("{:05}", fr.frame_at(t) + session.project.settings.frame_start),
-        TimeDisplayStyle::Timecode => {
-            let df = fr.supports_drop_frame();
-            let s = effectcraft_engine::time::format_timecode_frames(fr.frame_at(t + comp.display_start), fr, df);
-            if df { s } else { s.replace(';', ":") }
-        }
+        // AE's display: `0:00:02:15` (non-drop-frame counting, as AE shows new comps).
+        TimeDisplayStyle::Timecode => effectcraft_engine::time::format_timecode_ae(fr.frame_at(t + comp.display_start), fr, false),
     }
 }
 

crates/ui-egui/src/panels/project.rs

@@ -240,10 +240,8 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         if resp.double_clicked() {
             match &it.kind {
                 ItemKind::Comp(_) => actions.push(("comp.open".into(), json!({"comp": id.0}))),
-                ItemKind::Folder => {
-                    if !app.ui.project_open_folders.remove(&id.0) {
-                        app.ui.project_open_folders.insert(id.0);
-                    }
+                ItemKind::Folder if !app.ui.project_open_folders.remove(&id.0) => {
+                    app.ui.project_open_folders.insert(id.0);
                 }
                 _ => {}
             }

crates/ui-egui/src/panels/timeline.rs

@@ -21,8 +21,54 @@ use crate::{EffectcraftApp, widgets};
 #[derive(Clone, Debug)]
 enum RowKind {
     Layer,
-    Group { uid: u64, name: String, open: bool, has_children: bool, fx: Option<bool> },
-    Prop { uid: u64 },
+    Group {
+        uid: u64,
+        name: String,
+        open: bool,
+        has_children: bool,
+        fx: Option<bool>,
+    },
+    Prop {
+        uid: u64,
+    },
+    /// Inline expression editor under a property with an expression.
+    Expr {
+        uid: u64,
+        lines: usize,
+    },
+}
+
+/// Row height (expression editors grow with their text).
+fn row_height(row: &Row, rh: f32) -> f32 {
+    match row.kind {
+        RowKind::Expr { lines, .. } => rh * lines.clamp(1, 8) as f32 + 6.0,
+        _ => rh,
+    }
+}
+
+/// Insert an expression editor row after every property that has an expression.
+fn with_expr_rows(rows: Vec<Row>, comp: &Comp, closed: &std::collections::BTreeSet<u64>) -> Vec<Row> {
+    let mut out = Vec::with_capacity(rows.len());
+    for r in rows {
+        let extra = match r.kind {
+            RowKind::Prop { uid } if !closed.contains(&uid) => comp.layer(r.layer).and_then(|l| l.props.find(uid)).and_then(|p| p.expr.as_ref()).map(|e| Row {
+                layer: r.layer,
+                depth: r.depth,
+                kind: RowKind::Expr { uid, lines: e.text.lines().count().max(1) },
+            }),
+            _ => None,
+        };
+        out.push(r);
+        out.extend(extra);
+    }
+    out
+}
+
+/// A pick-whip drag in progress: (parent = 0 / property = 1, layer, prop uid, start point).
+type PickWhip = (u8, u64, u64, Pos2);
+
+fn pick_whip_id() -> egui::Id {
+    egui::Id::new("tl-pickwhip")
 }
 
 #[derive(Clone, Debug)]
@@ -42,7 +88,6 @@ struct Cols {
     label: f32,
     num: f32,
     name: f32,
-    name_w: f32,
     switches: f32,
     mode: f32,
     trkmat: f32,
@@ -61,22 +106,22 @@ fn cols(x0: f32, width: f32, show_modes: bool) -> Cols {
     let mode = switches + SW * 8.0 + 6.0;
     let trkmat = mode + if show_modes { 92.0 } else { 0.0 };
     let parent = trkmat + if show_modes { 112.0 } else { 0.0 };
-    Cols { av, label, num, name, name_w, switches, mode, trkmat, parent, end: parent + 116.0 }
+    Cols { av, label, num, name, switches, mode, trkmat, parent, end: parent + 116.0 }
 }
 
 /// Timeline horizontal mapping.
 #[derive(Clone, Copy, Debug)]
-struct TMap {
-    x0: f32,
-    start: f64,
-    pps: f64,
+pub(crate) struct TMap {
+    pub x0: f32,
+    pub start: f64,
+    pub pps: f64,
 }
 
 impl TMap {
-    fn x(&self, secs: f64) -> f32 {
+    pub fn x(&self, secs: f64) -> f32 {
         self.x0 + ((secs - self.start) * self.pps) as f32
     }
-    fn t(&self, x: f32) -> f64 {
+    pub fn t(&self, x: f32) -> f64 {
         self.start + (x - self.x0) as f64 / self.pps
     }
 }
@@ -141,6 +186,10 @@ fn prop_visible(p: &Property, layer: &Layer) -> bool {
     if p.two_d_only && layer.is_3d() {
         return false;
     }
+    // Separate Dimensions: X/Y/Z Position replace Position.
+    if p.match_id == "position" && layer.transform().is_some_and(|tr| tr.get("positionX").is_some() && tr.get("position").is_some_and(|q| q.uid == p.uid)) {
+        return false;
+    }
     true
 }
 
@@ -168,7 +217,7 @@ fn build_rows(app: &EffectcraftApp, comp: &Comp) -> Vec<Row> {
         }
         if let Some(kind) = tl.reveal.first() {
             let (group, props): (&str, Vec<&str>) = match kind.as_str() {
-                "position" => ("transform", vec!["position"]),
+                "position" => ("transform", vec!["position", "positionX", "positionY", "positionZ"]),
                 "scale" => ("transform", vec!["scale"]),
                 "rotation" => ("transform", vec!["rotation", "rotationX", "rotationY", "orientation"]),
                 "opacity" => ("transform", vec!["opacity"]),
@@ -322,7 +371,8 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     let ruler_h = 34.0;
     let colhdr_h = 22.0;
     let footer_h = 24.0;
-    let left_w = (rect.width() * 0.5).clamp(420.0, 860.0);
+    let fixed = AV_W + LABEL_W + NUM_W + SW * 8.0 + if app.ui.timeline.show_modes { 92.0 + 112.0 } else { 0.0 } + 116.0 + 6.0;
+    let left_w = (fixed + 190.0).clamp(420.0, (rect.width() * 0.62).max(420.0));
     let cw = cols(rect.min.x, left_w, app.ui.timeline.show_modes);
     let graph_x0 = rect.min.x + left_w + 1.0;
     let graph_x1 = rect.max.x - 10.0;
@@ -346,7 +396,7 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     let tc_rect = Rect::from_min_size(pos2(rect.min.x + 12.0, top + 6.0), vec2(150.0, 24.0));
     let tc_resp = ui.interact(tc_rect, egui::Id::new("tl-timecode"), Sense::click_and_drag());
     p.text(tc_rect.left_center(), Align2::LEFT_CENTER, &tc, Tokens::semibold(20.0), t.timecode);
-    let sub = format!("{} ({:.2} fps)", fr.frame_at(time), fr.as_f64());
+    let sub = format!("{:05} ({:.2} fps)", fr.frame_at(time) + app.session.project.settings.frame_start, fr.as_f64());
     p.text(pos2(tc_rect.min.x, tc_rect.max.y + 8.0), Align2::LEFT_CENTER, sub, Tokens::ui(10.5), t.text_faint);
     app.auto.add("timeline.timecode", tc_rect, &tc);
     if tc_resp.dragged() {
@@ -439,7 +489,7 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     let fd = comp.frame_duration().seconds();
     let cy0 = ruler.min.y + 11.0;
     let mut run: Option<(i64, i64)> = None;
-    let mut draw_run = |a: i64, b: i64| {
+    let draw_run = |a: i64, b: i64| {
         let x0 = tm.x(a as f64 * fd);
         let x1 = tm.x((b + 1) as f64 * fd);
         p.rect_filled(Rect::from_min_max(pos2(x0, cy0), pos2(x1, cy0 + 2.5)), 0.0, t.cache_green);
@@ -458,14 +508,26 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         draw_run(a, b);
     }
     // Ticks + labels.
-    let secs_per_label = [0.0333, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0, 10.0, 30.0, 60.0].into_iter().find(|s| s * pps >= 70.0).unwrap_or(60.0);
+    // Label spacing in whole frames (AE: `00:15f`-style seconds:frames labels).
+    let fps_i = fr.as_f64().round().max(1.0) as i64;
+    let half = (fps_i / 2).max(1);
+    let label_frames = [1, 2, 5, 10, half, fps_i, 2 * fps_i, 5 * fps_i, 10 * fps_i, 30 * fps_i, 60 * fps_i]
+        .into_iter()
+        .find(|f| *f as f64 * fd * pps >= 52.0)
+        .unwrap_or(60 * fps_i);
+    let secs_per_label = label_frames as f64 * fd;
     let first = (tm.start / secs_per_label).floor() * secs_per_label;
     let mut s = first;
     let pr = p.with_clip_rect(Rect::from_min_max(pos2(graph_x0, ruler.min.y), ruler.max));
     while s <= tm.t(graph_x1) + secs_per_label {
         let x = tm.x(s);
         pr.line_segment([pos2(x, ruler.max.y - 10.0), pos2(x, ruler.max.y)], Stroke::new(1.0, t.tl_ruler_tick));
-        let label = if secs_per_label < 1.0 { format!("{:02}f", fr.frame_at(Tick::from_seconds_f64(s + 1e-9))) } else { format!("{:02}s", s.round() as i64) };
+        let fno = (s / fd).round() as i64;
+        let label = if fno >= 60 * fps_i * 60 {
+            format!("{}:{:02}:{:02}f", fno / (fps_i * 60), (fno / fps_i) % 60, fno % fps_i)
+        } else {
+            format!("{:02}:{:02}f", fno / fps_i, fno % fps_i)
+        };
         pr.text(pos2(x + 3.0, ruler.max.y - 16.0), Align2::LEFT_CENTER, label, Tokens::ui(10.0), t.tl_ruler_text);
         for k in 1..5 {
             let xx = tm.x(s + secs_per_label * k as f64 / 5.0);
@@ -520,9 +582,9 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     let _ = cw.end;
 
     // ---- rows.
-    let rows = build_rows(app, &comp);
+    let rows = with_expr_rows(build_rows(app, &comp), &comp, &app.ui.timeline.expr_closed);
     let rh = t.row_h;
-    let total_h = rows.len() as f32 * rh;
+    let total_h: f32 = rows.iter().map(|r| row_height(r, rh)).sum();
     let max_scroll = (total_h - rows_rect.height() + rh).max(0.0);
     if ui.rect_contains_pointer(rows_rect) {
         let (dy, dx, zoom) = ui.input(|i| (i.smooth_scroll_delta.y, i.smooth_scroll_delta.x, i.modifiers.alt));
@@ -548,16 +610,27 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     let mut ui_actions: Vec<UiAct> = Vec::new();
     let idx_of = |id: LayerId| comp.index_of(id).unwrap_or(0);
     let graph_on = app.ui.timeline.graph_editor;
+    let full_clip = ui.clip_rect();
+    let left_clip = full_clip.intersect(Rect::from_min_max(pos2(rect.min.x, rows_rect.min.y), pos2(graph_x0 - 1.0, rows_rect.max.y)));
+    let right_clip = full_clip.intersect(Rect::from_min_max(pos2(graph_x0, rows_rect.min.y), rows_rect.max));
+    // Registered before the rows so keys, bars and editors on top of it get the pointer first.
+    let empty_rect = if graph_on { Rect::NOTHING } else { Rect::from_min_max(pos2(graph_x0, rows_rect.min.y), rows_rect.max) };
+    let empty = ui.interact(empty_rect, egui::Id::new("tl-graph-bg"), Sense::click_and_drag());
+    let mut hit_rows: Vec<(Rect, Row)> = vec![];
     for (ri, row) in rows.iter().enumerate() {
-        let r = Rect::from_min_size(pos2(rect.min.x, y), vec2(rect.width(), rh));
-        y += rh;
+        // Outline widgets never spill into the time graph (narrow timelines).
+        ui.set_clip_rect(left_clip);
+        let hh = row_height(row, rh);
+        let r = Rect::from_min_size(pos2(rect.min.x, y), vec2(rect.width(), hh));
+        y += hh;
         if r.max.y < rows_rect.min.y || r.min.y > rows_rect.max.y {
             continue;
         }
+        hit_rows.push((r, row.clone()));
         let Some(layer) = comp.layer(row.layer) else { continue };
         let is_sel = selected.contains(&layer.id);
         let left = Rect::from_min_max(r.min, pos2(graph_x0 - 1.0, r.max.y));
-        let cy = r.center().y;
+        let cy = r.min.y + rh / 2.0;
         match &row.kind {
             RowKind::Layer => {
                 lp.rect_filled(
@@ -739,7 +812,15 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     }
                 }
                 // Parent.
-                let pr_rect = Rect::from_min_size(pos2(cw.parent + 2.0, cy - 9.0), vec2(110.0, 18.0));
+                let pw_rect = Rect::from_center_size(pos2(cw.parent + 9.0, cy), vec2(15.0, 15.0));
+                let pw = ui.interact(pw_rect, egui::Id::new(("parent-whip", layer.id.0)), Sense::drag()).on_hover_text("Parent pick whip: drag onto a layer");
+                icons::paint(&lp, pw_rect.shrink(1.0), Icon::PickWhip, if pw.hovered() || pw.dragged() { t.text } else { t.text_dim });
+                app.auto.add(&format!("timeline.layer.{}.pickWhip", layer.id.0), pw_rect, "Parent pick whip");
+                if pw.drag_started() {
+                    let pw_state: PickWhip = (0, layer.id.0, 0, pw_rect.center());
+                    ctx.data_mut(|d| d.insert_temp(pick_whip_id(), pw_state));
+                }
+                let pr_rect = Rect::from_min_size(pos2(cw.parent + 20.0, cy - 9.0), vec2(94.0, 18.0));
                 let plabel = layer.parent.and_then(|p| comp.layer(p)).map(|l| format!("{}. {}", idx_of(l.id), l.name)).unwrap_or_else(|| "None".into());
                 let presp = widgets::dropdown(ui, pr_rect, &plabel, &t, egui::Id::new(("parent", layer.id.0)));
                 app.auto.add(&format!("timeline.layer.{}.parent", layer.id.0), pr_rect, "Parent");
@@ -755,6 +836,7 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     actions.push(("layer.setParent".into(), json!({"layers": [layer.id.0], "parent": par})));
                 }
                 // Layer bar.
+                ui.set_clip_rect(right_clip);
                 if !graph_on {
                     let x_in = tm.x(layer.in_point.seconds());
                     let x_out = tm.x(layer.out_point.seconds());
@@ -785,10 +867,8 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     if lin.hovered() || lout.hovered() || lin.dragged() || lout.dragged() {
                         ctx.set_cursor_icon(egui::CursorIcon::ResizeHorizontal);
                     }
-                    if body.clicked() || body.drag_started() {
-                        if !is_sel {
-                            actions.push(("layer.select".into(), json!({"layers": [layer.id.0], "add": ui.input(|i| i.modifiers.shift)})));
-                        }
+                    if (body.clicked() || body.drag_started()) && !is_sel {
+                        actions.push(("layer.select".into(), json!({"layers": [layer.id.0], "add": ui.input(|i| i.modifiers.shift)})));
                     }
                     layer_context_menu(&body, layer, &mut actions);
                     let drag_key = format!("bar-{}", layer.id.0);
@@ -875,6 +955,75 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     ui_actions.push(UiAct::ToggleGroup(*uid));
                 }
             }
+            RowKind::Expr { uid, lines } => {
+                let Some(prop) = layer.props.find(*uid) else { continue };
+                let Some(ex) = prop.expr.clone() else { continue };
+                lp.rect_filled(left, 0.0, t.row_alt);
+                let indent = cw.name + 6.0 + 14.0 * row.depth as f32;
+                lp.text(pos2(indent + 12.0, cy), Align2::LEFT_CENTER, "Expression:", Tokens::ui(11.5), t.text_dim);
+                lp.text(pos2(indent + 82.0, cy), Align2::LEFT_CENTER, &prop.name, Tokens::ui(11.5), t.text);
+                // "=" enable switch and the property pick whip (AE's expression controls).
+                let en_r = Rect::from_center_size(pos2(cw.switches + 10.0, cy), vec2(16.0, 16.0));
+                let en = ui.interact(en_r, egui::Id::new(("expr-en", uid)), Sense::click()).on_hover_text("Enable Expression");
+                lp.rect_stroke(en_r.shrink(1.0), 2.0, Stroke::new(1.0, t.separator), StrokeKind::Inside);
+                let expr_col = Color32::from_rgb(0xe8, 0x7c, 0x5c);
+                lp.text(
+                    en_r.center(),
+                    Align2::CENTER_CENTER,
+                    if ex.enabled { "=" } else { "≠" },
+                    Tokens::semibold(13.0),
+                    if ex.enabled { expr_col } else { t.text_dim },
+                );
+                app.auto.add(&format!("timeline.prop.{uid}.exprEnable"), en_r, "Enable Expression");
+                if en.clicked() {
+                    actions.push(("prop.setExpression".into(), json!({"layer": layer.id.0, "prop": uid, "enabled": !ex.enabled})));
+                }
+                let pw_rect = Rect::from_center_size(pos2(cw.switches + 30.0, cy), vec2(15.0, 15.0));
+                let pw = ui.interact(pw_rect, egui::Id::new(("expr-whip", uid)), Sense::drag()).on_hover_text("Expression pick whip: drag onto a property");
+                icons::paint(&lp, pw_rect.shrink(1.0), Icon::PickWhip, if pw.hovered() || pw.dragged() { t.text } else { t.text_dim });
+                app.auto.add(&format!("timeline.prop.{uid}.pickWhip"), pw_rect, "Expression pick whip");
+                if pw.drag_started() {
+                    let pw_state: PickWhip = (1, layer.id.0, *uid, pw_rect.center());
+                    ctx.data_mut(|d| d.insert_temp(pick_whip_id(), pw_state));
+                }
+                // Syntax errors: warning in the outline (the expression is disabled).
+                if let Some(check) = app.session.expr_check
+                    && let Err(e) = check(&ex.text)
+                {
+                    let wr = Rect::from_center_size(pos2(cw.switches + 50.0, cy), vec2(14.0, 14.0));
+                    lp.text(wr.center(), Align2::CENTER_CENTER, "⚠", Tokens::ui(12.0), Color32::from_rgb(0xf0, 0xa0, 0x30));
+                    let _ = ui.interact(wr, egui::Id::new(("expr-err", uid)), Sense::hover()).on_hover_text(e);
+                }
+                // The editor in the time-graph area.
+                ui.set_clip_rect(right_clip);
+                gp.rect_filled(Rect::from_min_max(pos2(graph_x0, r.min.y), r.max), 0.0, Color32::from_rgb(0x1a, 0x1a, 0x1a));
+                let er = Rect::from_min_max(pos2(graph_x0 + 8.0, r.min.y + 3.0), pos2(rect.max.x - 14.0, r.max.y - 3.0));
+                let buf_id = egui::Id::new(("expr-buf", uid));
+                let mut buf: String = ctx.data(|d| d.get_temp(buf_id)).unwrap_or_else(|| ex.text.clone());
+                let mut child = ui.new_child(egui::UiBuilder::new().max_rect(er));
+                let resp = child.add(
+                    egui::TextEdit::multiline(&mut buf)
+                        .id(egui::Id::new(("expr-edit", uid)))
+                        .font(Tokens::mono(11.5))
+                        .text_color(if ex.enabled { expr_col } else { t.text_dim })
+                        .desired_width(er.width())
+                        .desired_rows((*lines).clamp(1, 8))
+                        .frame(egui::Frame::NONE),
+                );
+                app.auto.add(&format!("timeline.prop.{uid}.expression"), er, &prop.name);
+                let commit = resp.has_focus() && ui.input(|i| i.key_pressed(egui::Key::Enter) && (i.modifiers.command || i.modifiers.ctrl));
+                if commit {
+                    resp.surrender_focus();
+                }
+                if resp.has_focus() && !commit {
+                    ctx.data_mut(|d| d.insert_temp(buf_id, buf));
+                } else {
+                    if (resp.lost_focus() || commit) && buf.trim_end() != ex.text {
+                        actions.push(("prop.setExpression".into(), json!({"layer": layer.id.0, "prop": uid, "expression": buf.trim_end()})));
+                    }
+                    ctx.data_mut(|d| d.remove::<String>(buf_id));
+                }
+            }
             RowKind::Prop { uid } => {
                 let Some(prop) = layer.props.find(*uid) else { continue };
                 let sel_prop = app.session.state.selected_props.contains(&(layer.id, *uid));
@@ -961,8 +1110,9 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                 let value = ectx.value(layer, prop);
                 let vx = (cw.switches + 4.0).max(name_x + 120.0);
                 value_editor(app, ui, &lp, layer, prop, &value, pos2(vx, cy), &mut actions);
+                ui.set_clip_rect(right_clip);
                 // Expression text row hint.
-                if let Some(e) = prop.expr.as_ref().filter(|e| e.enabled) {
+                if let Some(e) = prop.expr.as_ref().filter(|e| e.enabled && app.ui.timeline.expr_closed.contains(uid)) {
                     gp.text(
                         pos2(graph_x0 + 8.0, cy),
                         Align2::LEFT_CENTER,
@@ -1001,15 +1151,32 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                         }
                         kresp.context_menu(|ui| {
                             for (lbl, cmd, params) in [
+                                ("Copy", "keys.copy", json!({})),
+                                ("Paste", "keys.paste", json!({})),
+                                ("-", "", json!({})),
+                                ("Keyframe Interpolation…", "keys.interpolation", json!({})),
+                                ("Keyframe Velocity…", "keys.velocity", json!({})),
+                                ("Toggle Hold Keyframe", "keys.toggleHold", json!({})),
+                                ("Rove Across Time", "keys.interpolation", json!({"roving": !k.roving})),
+                                ("-", "", json!({})),
                                 ("Easy Ease", "keys.easyEase", json!({})),
                                 ("Easy Ease In", "keys.easyEaseIn", json!({})),
                                 ("Easy Ease Out", "keys.easyEaseOut", json!({})),
-                                ("Toggle Hold Keyframe", "keys.toggleHold", json!({})),
+                                ("Time-Reverse Keyframes", "keys.timeReverse", json!({})),
+                                ("-", "", json!({})),
                                 ("Linear", "keys.interpolation", json!({"interpolation": "linear"})),
                                 ("Bezier", "keys.interpolation", json!({"interpolation": "bezier"})),
-                                ("Auto Bezier", "keys.interpolation", json!({"autoBezier": true})),
+                                ("Auto Bezier", "keys.interpolation", json!({"interpolation": "autoBezier"})),
+                                ("Select All Keyframes", "keys.selectAll", json!({})),
                                 ("Delete", "keys.delete", json!({})),
                             ] {
+                                if lbl == "-" {
+                                    ui.separator();
+                                    continue;
+                                }
+                                if lbl == "Rove Across Time" && !prop.spatial {
+                                    continue;
+                                }
                                 if ui.button(lbl).clicked() {
                                     if !ks {
                                         actions.push(("keys.select".into(), json!({"keys": [{"layer": layer.id.0, "prop": uid, "time": k.time.seconds()}]})));
@@ -1039,17 +1206,40 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
             }
         }
     }
+    ui.set_clip_rect(full_clip);
+    // Pick whips: a line follows the pointer; releasing over a row links to it.
+    if let Some((kind, src_layer, src_prop, start)) = ctx.data(|d| d.get_temp::<PickWhip>(pick_whip_id())) {
+        let ptr = ctx.input(|i| i.pointer.latest_pos()).unwrap_or(start);
+        let fg = ctx.layer_painter(egui::LayerId::new(egui::Order::Foreground, egui::Id::new("tl-pickwhip-line")));
+        fg.line_segment([start, ptr], Stroke::new(1.5, t.accent));
+        fg.circle_stroke(ptr, 4.0, Stroke::new(1.5, t.accent));
+        let target = hit_rows.iter().find(|(r, _)| r.contains(ptr)).map(|(r, row)| (*r, row.clone()));
+        if let Some((tr, _)) = &target {
+            fg.rect_stroke(Rect::from_min_max(tr.min, pos2(graph_x0 - 1.0, tr.max.y)), 0.0, Stroke::new(1.0, t.accent), StrokeKind::Inside);
+        }
+        if ctx.input(|i| !i.pointer.any_down()) {
+            ctx.data_mut(|d| d.remove::<PickWhip>(pick_whip_id()));
+            match (kind, target) {
+                (0, Some((_, row))) if row.layer.0 != src_layer => {
+                    actions.push(("layer.setParent".into(), json!({"layers": [src_layer], "parent": row.layer.0})));
+                }
+                (1, Some((_, Row { layer, kind: RowKind::Prop { uid }, .. }))) if uid != src_prop => {
+                    actions.push(("prop.pickWhip".into(), json!({"layer": src_layer, "prop": src_prop, "target": {"layer": layer.0, "prop": uid}})));
+                }
+                _ => {}
+            }
+        }
+    }
     // Graph editor.
     if graph_on {
-        graph_editor(app, ui, &gp, &comp, &ectx, tm, Rect::from_min_max(pos2(graph_x0, rows_rect.min.y), rows_rect.max));
+        super::graph::show(app, ui, &gp, &comp, &ectx, tm, Rect::from_min_max(pos2(graph_x0, rows_rect.min.y), rows_rect.max), &mut actions);
     }
     // Empty-area click in the graph: deselect keys; drag: box-select keys.
-    let empty = ui.interact(Rect::from_min_max(pos2(graph_x0, rows_rect.min.y), rows_rect.max), egui::Id::new("tl-graph-bg"), Sense::click_and_drag());
     if empty.clicked() {
         actions.push(("keys.select".into(), json!({"keys": []})));
     }
     if let (true, Some(origin), Some(cur)) =
-        (empty.dragged(), empty.interact_pointer_pos().map(|_| ctx.input(|i| i.pointer.press_origin())).flatten(), empty.interact_pointer_pos())
+        (empty.dragged(), empty.interact_pointer_pos().and_then(|_| ctx.input(|i| i.pointer.press_origin())), empty.interact_pointer_pos())
     {
         let br = Rect::from_two_pos(origin, cur);
         gp.rect_filled(br, 0.0, t.accent.gamma_multiply(0.12));
@@ -1064,7 +1254,7 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         let mut yy = rows_rect.min.y - app.ui.timeline.scroll_y;
         for row in &rows {
             let cy = yy + rh / 2.0;
-            yy += rh;
+            yy += row_height(row, rh);
             if let RowKind::Prop { uid } = row.kind
                 && cy >= br.min.y
                 && cy <= br.max.y
@@ -1140,8 +1330,7 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         p.rect_stroke(rows_rect, 0.0, Stroke::new(2.0, t.accent), StrokeKind::Inside);
         if ctx.input(|i| i.pointer.any_released()) {
             let hover_y = ctx.input(|i| i.pointer.hover_pos()).map(|p| p.y).unwrap_or(0.0);
-            let row_i = ((hover_y - rows_rect.min.y + app.ui.timeline.scroll_y) / rh).floor() as usize;
-            let target = rows.get(row_i).map(|r| r.layer);
+            let target = hit_rows.iter().find(|(r, _)| hover_y >= r.min.y && hover_y < r.max.y).map(|(_, row)| row.layer);
             match payload.as_ref() {
                 crate::panels::DragPayload::Item(id) => actions.push(("layer.addItem".into(), json!({"item": id}))),
                 crate::panels::DragPayload::Effect(e) => {
@@ -1188,6 +1377,10 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         }
     }
     for (id, params) in actions {
+        if id == "__endMerge" {
+            app.session.history.merge_key = None;
+            continue;
+        }
         if let Err(e) = crate::menus::invoke(app, &ctx, &id, params) {
             app.ui.status = e;
         }
@@ -1257,7 +1450,11 @@ fn layer_context_menu(resp: &egui::Response, layer: &Layer, actions: &mut Vec<(S
             item(ui, "Flip Vertical", "layer.transform", json!({"layers": [id], "op": "flipV"}));
         });
         ui.menu_button("Time", |ui| {
-            item(ui, "Time-Reverse Layer", "layer.timeStretch", json!({"layers": [id], "op": "reverse"}));
+            item(ui, "Enable Time Remapping", "layer.enableTimeRemap", json!({"layers": [id]}));
+            item(ui, "Time-Reverse Layer", "layer.timeReverse", json!({"layers": [id]}));
+            item(ui, "Time Stretch…", "layer.timeStretch", json!({}));
+            item(ui, "Freeze Frame", "layer.freezeFrame", json!({"layers": [id]}));
+            item(ui, "Freeze on Last Frame", "layer.freezeOnLastFrame", json!({"layers": [id]}));
         });
         ui.menu_button("Blending Mode", |ui| {
             for m in BlendMode::ALL {
@@ -1412,86 +1609,3 @@ fn value_editor(
         }
     }
 }
-
-/// Value graph of the selected properties (numeric dimensions over time) with key markers.
-fn graph_editor(app: &mut EffectcraftApp, ui: &mut egui::Ui, p: &egui::Painter, comp: &Comp, ectx: &EvalCtx, tm: TMap, area: Rect) {
-    let t = app.tokens;
-    let props: Vec<(LayerId, u64)> = if app.session.state.selected_props.is_empty() {
-        // Default: animated properties of selected layers.
-        let mut v = vec![];
-        for l in comp.layers.iter().filter(|l| app.session.state.selected_layers.contains(&l.id)) {
-            l.props.walk("", &mut |_, pr| {
-                if pr.is_animated() && !pr.value.components().is_empty() {
-                    v.push((l.id, pr.uid));
-                }
-            });
-        }
-        v
-    } else {
-        app.session.state.selected_props.clone()
-    };
-    p.rect_filled(area, 0.0, Color32::from_rgb(0x1e, 0x1e, 0x1e));
-    // Grid.
-    for i in 1..8 {
-        let y = area.min.y + area.height() * i as f32 / 8.0;
-        p.line_segment([pos2(area.min.x, y), pos2(area.max.x, y)], Stroke::new(1.0, Color32::from_white_alpha(10)));
-    }
-    if props.is_empty() {
-        p.text(area.center(), Align2::CENTER_CENTER, "Select animated properties to show them in the Graph Editor", Tokens::ui(12.0), t.text_faint);
-        return;
-    }
-    let colors =
-        [Color32::from_rgb(0xe0, 0x50, 0x50), Color32::from_rgb(0x60, 0xd0, 0x60), Color32::from_rgb(0x50, 0x8c, 0xf0), Color32::from_rgb(0xe8, 0xc8, 0x40)];
-    // Sample all curves over the visible span; normalise to a common range.
-    let n = ((area.width() / 2.0) as usize).max(2);
-    let mut curves: Vec<(Vec<Vec<f64>>, &Layer, &Property)> = vec![];
-    let (mut lo, mut hi) = (f64::INFINITY, f64::NEG_INFINITY);
-    for (lid, uid) in &props {
-        let Some(l) = comp.layer(*lid) else { continue };
-        let Some(pr) = l.props.find(*uid) else { continue };
-        let mut dims: Vec<Vec<f64>> = vec![];
-        for i in 0..n {
-            let x = area.min.x + area.width() * i as f32 / (n - 1) as f32;
-            let tt = Tick::from_seconds_f64(tm.t(x));
-            let v = ectx.at(tt).value(l, pr).components();
-            if dims.is_empty() {
-                dims = vec![Vec::with_capacity(n); v.len().min(3)];
-            }
-            for (d, c) in v.iter().take(dims.len()).enumerate() {
-                dims[d].push(*c);
-                lo = lo.min(*c);
-                hi = hi.max(*c);
-            }
-        }
-        curves.push((dims, l, pr));
-    }
-    if !lo.is_finite() || !hi.is_finite() {
-        return;
-    }
-    if (hi - lo).abs() < 1e-9 {
-        hi = lo + 1.0;
-    }
-    let pad = (hi - lo) * 0.1;
-    let (lo, hi) = (lo - pad, hi + pad);
-    let ymap = |v: f64| area.max.y - ((v - lo) / (hi - lo)) as f32 * area.height();
-    for (dims, l, pr) in &curves {
-        for (d, vals) in dims.iter().enumerate() {
-            let pts: Vec<Pos2> = vals.iter().enumerate().map(|(i, v)| pos2(area.min.x + area.width() * i as f32 / (n - 1) as f32, ymap(*v))).collect();
-            p.add(egui::Shape::line(pts, Stroke::new(1.5, colors[d % colors.len()])));
-        }
-        for k in &pr.keys {
-            let x = tm.x(l.comp_time(k.time).seconds());
-            for (d, v) in k.value.components().iter().take(dims.len()).enumerate() {
-                let c = pos2(x, ymap(*v));
-                p.rect_filled(Rect::from_center_size(c, vec2(6.0, 6.0)), 0.0, Color32::WHITE);
-                p.rect_stroke(Rect::from_center_size(c, vec2(6.0, 6.0)), 0.0, Stroke::new(1.0, colors[d % colors.len()]), StrokeKind::Outside);
-            }
-        }
-    }
-    // Value labels.
-    for i in 0..=4 {
-        let v = lo + (hi - lo) * i as f64 / 4.0;
-        p.text(pos2(area.min.x + 4.0, ymap(v)), Align2::LEFT_BOTTOM, format!("{v:.1}"), Tokens::ui(10.0), t.text_faint);
-    }
-    let _ = ui;
-}

crates/ui-egui/src/panels/viewer.rs

@@ -55,13 +55,82 @@ pub fn last_fit(ctx: &egui::Context) -> f32 {
 /// What a drag in the viewer is doing.
 #[derive(Clone, Debug)]
 enum Gesture {
-    Move { layers: Vec<(LayerId, [f64; 3], Mat3)>, start: [f64; 2] },
-    Scale { layer: LayerId, anchor_screen: Pos2, start_scale: [f64; 3], start_local: [f64; 2], inv: Mat3, uniform: bool },
-    Rotate { layer: LayerId, center: Pos2, start_angle: f64, start_rot: f64 },
-    Anchor { layer: LayerId, start_anchor: [f64; 3], start_pos: [f64; 3], start: [f64; 2], inv: Mat3, l2p: Mat3 },
-    Pan { start_pan: [f32; 2] },
-    Create { tool: Tool, start: [f64; 2] },
-    Marquee { start: Pos2 },
+    Move {
+        layers: Vec<(LayerId, [f64; 3], Mat3)>,
+        start: [f64; 2],
+    },
+    Scale {
+        layer: LayerId,
+        start_scale: [f64; 3],
+        start_local: [f64; 2],
+        inv: Mat3,
+    },
+    Rotate {
+        layer: LayerId,
+        center: Pos2,
+        start_angle: f64,
+        start_rot: f64,
+    },
+    Anchor {
+        layer: LayerId,
+        start_anchor: [f64; 3],
+        start_pos: [f64; 3],
+        start: [f64; 2],
+        inv: Mat3,
+        l2p: Mat3,
+    },
+    Pan {
+        start_pan: [f32; 2],
+    },
+    Create {
+        tool: Tool,
+        start: [f64; 2],
+    },
+    Marquee {
+        start: Pos2,
+    },
+    /// Dragging selected mask vertices (comp-space point of the previous frame, comp → layer).
+    Vertices {
+        last: [f64; 2],
+        inv: Mat3,
+    },
+    /// Dragging a vertex's Bezier tangent (both sides symmetric unless Alt breaks them).
+    Tangent {
+        layer: LayerId,
+        mask: u64,
+        index: usize,
+        out: bool,
+        vertex: [f64; 2],
+        inv: Mat3,
+    },
+    /// Pen tool: pulling the tangents of the vertex just placed.
+    Pen {
+        layer: LayerId,
+        mask: u64,
+        index: usize,
+        vertex: [f64; 2],
+        inv: Mat3,
+        press: Pos2,
+    },
+}
+
+/// Pen tool path in progress: (layer, mask uid).
+fn pen_id() -> egui::Id {
+    egui::Id::new("viewer-pen")
+}
+
+/// Mask vertex / tangent hit targets drawn this frame.
+#[derive(Clone, Copy)]
+struct VertexHit {
+    layer: LayerId,
+    mask: u64,
+    index: usize,
+    pos: Pos2,
+    /// None = the vertex itself, Some(out?) = a tangent handle.
+    tangent: Option<bool>,
+    /// Layer-space vertex position and layer → comp matrix.
+    vertex: [f64; 2],
+    l2c: Mat3,
 }
 
 const HANDLE: f32 = 7.0;
@@ -251,6 +320,12 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     let ectx = EvalCtx { project: &snap_project, comp_id: cid, comp: &comp, time, expr: snap_expr.as_deref() };
     let selected = app.session.state.selected_layers.clone();
     let mut handle_hits: Vec<(LayerId, usize, Pos2)> = Vec::new();
+    let mut vertex_hits: Vec<VertexHit> = Vec::new();
+    let sel_vertices = app.session.state.selected_vertices.clone();
+    // Pen path in progress ends when the tool changes or its mask is gone.
+    if app.ui.tool != Tool::Pen || ui.input(|i| i.key_pressed(egui::Key::Escape) || i.key_pressed(egui::Key::Enter)) {
+        ui.data_mut(|d| d.remove::<(LayerId, u64)>(pen_id()));
+    }
     if app.ui.viewer.show_layer_controls {
         for l in comp.layers.iter().filter(|l| selected.contains(&l.id) && l.is_active_at(time)) {
             let col = Tokens::label(l.label);
@@ -300,14 +375,37 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     if sp.closed && !pts.is_empty() {
                         pts.push(pts[0]);
                     }
-                    painter.add(egui::Shape::line(pts, Stroke::new(1.0, Color32::from_rgb(color[0], color[1], color[2]))));
-                    for v in &sp.vertices {
-                        let c = m.apply(gv2(v[0], v[1]));
-                        painter.rect_filled(
-                            Rect::from_center_size(map.to_screen([c.x, c.y]), vec2(5.0, 5.0)),
-                            0.0,
-                            Color32::from_rgb(color[0], color[1], color[2]),
-                        );
+                    let mc = Color32::from_rgb(color[0], color[1], color[2]);
+                    painter.add(egui::Shape::line(pts, Stroke::new(1.0, mc)));
+                    let scr = |p: [f64; 2]| {
+                        let c = m.apply(gv2(p[0], p[1]));
+                        map.to_screen([c.x, c.y])
+                    };
+                    for (i, v) in sp.vertices.iter().enumerate() {
+                        let s = scr(*v);
+                        let selected = sel_vertices.iter().any(|x| x.layer == l.id && x.mask == g.uid && x.index == i);
+                        // Selected vertices: filled with their tangent handles; others hollow.
+                        if selected {
+                            for (out, tg) in [(false, sp.in_tangents.get(i)), (true, sp.out_tangents.get(i))] {
+                                let Some(tg) = tg.filter(|t| t[0] != 0.0 || t[1] != 0.0) else { continue };
+                                let h = scr([v[0] + tg[0], v[1] + tg[1]]);
+                                painter.line_segment([s, h], Stroke::new(1.0, mc));
+                                painter.circle_filled(h, 3.0, mc);
+                                vertex_hits.push(VertexHit { layer: l.id, mask: g.uid, index: i, pos: h, tangent: Some(out), vertex: *v, l2c: m });
+                            }
+                            painter.rect_filled(Rect::from_center_size(s, vec2(6.0, 6.0)), 0.0, mc);
+                        } else {
+                            painter.rect_filled(Rect::from_center_size(s, vec2(6.0, 6.0)), 0.0, Color32::from_black_alpha(160));
+                            painter.rect_stroke(Rect::from_center_size(s, vec2(6.0, 6.0)), 0.0, Stroke::new(1.0, mc), StrokeKind::Inside);
+                        }
+                        app.auto.add(&format!("viewer.mask.{}.vertex.{i}", g.uid), Rect::from_center_size(s, vec2(8.0, 8.0)), &g.name);
+                        vertex_hits.push(VertexHit { layer: l.id, mask: g.uid, index: i, pos: s, tangent: None, vertex: *v, l2c: m });
+                    }
+                    // Pen rubber band from the last vertex to the pointer.
+                    if ui.data(|d| d.get_temp::<(LayerId, u64)>(pen_id())) == Some((l.id, g.uid))
+                        && let (Some(last), Some(hp)) = (sp.vertices.last(), ui.input(|i| i.pointer.hover_pos()))
+                    {
+                        painter.line_segment([scr(*last), hp], Stroke::new(1.0, mc.gamma_multiply(0.6)));
                     }
                 }
             }
@@ -399,10 +497,31 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     }
     let mods = ui.input(|i| i.modifiers);
     let space_pan = ui.input(|i| i.key_down(egui::Key::Space)) && !ctx.egui_wants_keyboard_input();
+    // Pen tool: each press places a vertex (dragging pulls Bezier tangents); pressing on the
+    // first vertex closes the path.
+    if app.ui.tool == Tool::Pen
+        && !space_pan
+        && resp.hovered()
+        && ui.input(|i| i.pointer.primary_pressed())
+        && let Some(pos) = ui.input(|i| i.pointer.press_origin())
+    {
+        pen_press(app, ui, &ectx, &map, &vertex_hits, pos);
+    }
+    // A pen click (press + release without a drag) ends its tangent gesture on release.
+    if ui.input(|i| i.pointer.primary_released())
+        && matches!(ui.data(|d| d.get_temp::<Gesture>(egui::Id::new("viewer-gesture"))), Some(Gesture::Pen { .. }))
+        && !resp.drag_stopped()
+    {
+        ui.data_mut(|d| d.remove::<Gesture>(egui::Id::new("viewer-gesture")));
+    }
+    let vertex_at = |pos: Pos2, tangents: bool| -> Option<VertexHit> {
+        vertex_hits.iter().rev().filter(|h| h.tangent.is_some() == tangents).find(|h| h.pos.distance(pos) < 6.0).copied()
+    };
     if resp.drag_started()
         && let Some(pos) = resp.interact_pointer_pos()
     {
         let cpt = map.to_comp(pos);
+        let press = ui.input(|i| i.pointer.press_origin()).unwrap_or(pos);
         let tool = if space_pan || resp.dragged_by(egui::PointerButton::Middle) { Tool::Hand } else { app.ui.tool };
         let g = match tool {
             Tool::Hand => Some(Gesture::Pan { start_pan: app.ui.viewer.pan }),
@@ -432,6 +551,22 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                 })
             }),
             t if t.is_shape() => Some(Gesture::Create { tool: t, start: cpt }),
+            Tool::Selection if vertex_at(press, true).is_some() => vertex_at(press, true).map(|h| Gesture::Tangent {
+                layer: h.layer,
+                mask: h.mask,
+                index: h.index,
+                out: h.tangent == Some(true),
+                vertex: h.vertex,
+                inv: h.l2c.inverse().unwrap_or(Mat3::IDENTITY),
+            }),
+            Tool::Selection if vertex_at(press, false).is_some() => vertex_at(press, false).map(|h| {
+                let me = json!({"layer": h.layer.0, "mask": h.mask, "index": h.index});
+                let selected = app.session.state.selected_vertices.iter().any(|v| v.layer == h.layer && v.mask == h.mask && v.index == h.index);
+                if !selected {
+                    let _ = app.session.execute("mask.selectVertices", json!({"vertices": [me], "add": mods.shift}));
+                }
+                Gesture::Vertices { last: cpt, inv: h.l2c.inverse().unwrap_or(Mat3::IDENTITY) }
+            }),
             Tool::Selection => {
                 if let Some((lid, hi, _)) = handle_hits.iter().find(|(_, _, h)| h.distance(pos) < HANDLE + 2.0).cloned() {
                     let layer = comp.layer(lid).cloned();
@@ -440,17 +575,9 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                         let (l2c, _) = ectx.layer_to_comp(&layer);
                         let inv = l2c.inverse()?;
                         let a = ectx.v3(&layer, tr, "anchor", [0.0; 3]);
-                        let ac = l2c.apply(gv2(a[0], a[1]));
                         let lp = inv.apply(gv2(cpt[0], cpt[1]));
                         let _ = hi;
-                        Some(Gesture::Scale {
-                            layer: lid,
-                            anchor_screen: map.to_screen([ac.x, ac.y]),
-                            start_scale: ectx.v3(&layer, tr, "scale", [100.0; 3]),
-                            start_local: [lp.x - a[0], lp.y - a[1]],
-                            inv,
-                            uniform: hi < 4,
-                        })
+                        Some(Gesture::Scale { layer: lid, start_scale: ectx.v3(&layer, tr, "scale", [100.0; 3]), start_local: [lp.x - a[0], lp.y - a[1]], inv })
                     })
                 } else if let Some(l) = pick(app, &ectx, cpt, mods.shift) {
                     let layers: Vec<(LayerId, [f64; 3], Mat3)> = app
@@ -495,14 +622,14 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     let _ = app.session.execute("prop.set", json!({"layer": lid.0, "path": "transform/position", "value": v, "merge": merge}));
                 }
             }
-            Gesture::Scale { layer, start_scale, start_local, inv, uniform, .. } => {
+            Gesture::Scale { layer, start_scale, start_local, inv, .. } => {
                 let lp = inv.apply(gv2(cpt[0], cpt[1]));
                 // Local point relative to the anchor in *unscaled* layer space.
                 let a = comp.layer(layer).and_then(|l| l.transform().map(|tr| ectx.v3(l, tr, "anchor", [0.0; 3]))).unwrap_or([0.0; 3]);
                 let cur = [lp.x - a[0], lp.y - a[1]];
                 let fx = if start_local[0].abs() > 1e-6 { cur[0] / start_local[0] } else { 1.0 };
                 let fy = if start_local[1].abs() > 1e-6 { cur[1] / start_local[1] } else { 1.0 };
-                let (fx, fy) = if mods.shift || uniform && start_local[0].abs() > 1e-6 && start_local[1].abs() > 1e-6 && mods.shift {
+                let (fx, fy) = if mods.shift {
                     let f = (fx + fy) / 2.0;
                     (f, f)
                 } else {
@@ -564,6 +691,32 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                 let r = Rect::from_two_pos(a, pos);
                 painter.rect_stroke(r, 0.0, Stroke::new(1.0, t.accent), StrokeKind::Middle);
             }
+            Gesture::Vertices { last, inv } => {
+                let d = inv.apply_vec(gv2(cpt[0] - last[0], cpt[1] - last[1]));
+                if d.x != 0.0 || d.y != 0.0 {
+                    let _ = app.session.execute("mask.moveVertices", json!({"delta": [d.x, d.y], "merge": merge}));
+                }
+                ui.data_mut(|dd| dd.insert_temp(gid, Gesture::Vertices { last: cpt, inv }));
+            }
+            Gesture::Tangent { layer, mask, index, out, vertex, inv } => {
+                let lp = inv.apply(gv2(cpt[0], cpt[1]));
+                let t = [lp.x - vertex[0], lp.y - vertex[1]];
+                let mut params = json!({"layer": layer.0, "mask": mask, "index": index, "merge": merge});
+                params[if out { "out" } else { "in" }] = json!(t);
+                if !mods.alt {
+                    params[if out { "in" } else { "out" }] = json!([-t[0], -t[1]]);
+                }
+                let _ = app.session.execute("mask.setVertex", params);
+            }
+            Gesture::Pen { layer, mask, index, vertex, inv, press } => {
+                if pos.distance(press) > 3.0 {
+                    let lp = inv.apply(gv2(cpt[0], cpt[1]));
+                    let t = [lp.x - vertex[0], lp.y - vertex[1]];
+                    let _ = app
+                        .session
+                        .execute("mask.setVertex", json!({"layer": layer.0, "mask": mask, "index": index, "out": t, "in": [-t[0], -t[1]], "merge": merge}));
+                }
+            }
             Gesture::Marquee { start } => {
                 let r = Rect::from_two_pos(start, pos);
                 painter.rect_filled(r, 0.0, t.accent.gamma_multiply(0.12));
@@ -620,6 +773,13 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
                     ui.data_mut(|d| d.insert_temp(egui::Id::new("viewer-text-edit"), (v["layer"].as_u64().unwrap_or(0), "Text".to_string())));
                 }
             }
+            Tool::Pen => {}
+            Tool::Selection if vertex_at(pos, false).is_some() => {
+                if let Some(h) = vertex_at(pos, false) {
+                    let me = json!({"layer": h.layer.0, "mask": h.mask, "index": h.index});
+                    let _ = app.session.execute("mask.selectVertices", json!({"vertices": [me], "add": mods.shift, "toggle": mods.shift}));
+                }
+            }
             _ => {
                 if pick(app, &ectx, cpt, mods.shift).is_none() {
                     let _ = app.session.execute("edit.deselectAll", json!({}));
@@ -628,6 +788,7 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
         }
     }
     if resp.double_clicked()
+        && app.ui.tool != Tool::Pen
         && let Some(pos) = resp.interact_pointer_pos()
     {
         let cpt = map.to_comp(pos);
@@ -654,6 +815,51 @@ pub fn show(app: &mut EffectcraftApp, ui: &mut egui::Ui, rect: Rect) {
     bottom_bar(app, ui, bar, zoom, fit, time, &comp);
 }
 
+/// Pen tool press at `pos`: start a mask on the selected layer, add a vertex, or close the path.
+fn pen_press(app: &mut EffectcraftApp, ui: &mut egui::Ui, ectx: &EvalCtx, map: &ViewerMap, hits: &[VertexHit], pos: Pos2) {
+    let gid = egui::Id::new("viewer-gesture");
+    let current: Option<(LayerId, u64)> = ui.data(|d| d.get_temp(pen_id()));
+    let target = current.map(|c| c.0).or_else(|| {
+        app.session.state.selected_layers.iter().copied().find(|id| ectx.comp.layer(*id).is_some_and(|l| l.masks().is_some() && !l.switches.locked))
+    });
+    let Some(lid) = target else {
+        app.ui.status = "Select a layer to draw a mask with the Pen tool".into();
+        return;
+    };
+    let Some(layer) = ectx.comp.layer(lid) else { return };
+    let l2c = ectx.layer_to_comp(layer).0;
+    let Some(inv) = l2c.inverse() else { return };
+    let c = map.to_comp(pos);
+    let lp = inv.apply(gv2(c[0], c[1]));
+    let lp = [lp.x, lp.y];
+    let still_there = current.is_some_and(|(l, m)| layer.masks().is_some_and(|ms| ms.find_group(m).is_some()) && l == lid);
+    if let (true, Some((_, mask))) = (still_there, current) {
+        let count = hits.iter().filter(|h| h.layer == lid && h.mask == mask && h.tangent.is_none()).count();
+        let first = hits.iter().find(|h| h.layer == lid && h.mask == mask && h.index == 0 && h.tangent.is_none());
+        if count >= 2 && first.is_some_and(|f| f.pos.distance(pos) < 8.0) {
+            let _ = app.session.execute("mask.setClosed", json!({"layer": lid.0, "mask": mask, "closed": true}));
+            ui.data_mut(|d| {
+                d.remove::<(LayerId, u64)>(pen_id());
+                d.remove::<Gesture>(gid);
+            });
+            return;
+        }
+        if let Ok(v) = app.session.execute("mask.addVertex", json!({"layer": lid.0, "mask": mask, "point": lp})) {
+            let index = v.as_u64().unwrap_or(0) as usize;
+            ui.data_mut(|d| d.insert_temp(gid, Gesture::Pen { layer: lid, mask, index, vertex: lp, inv, press: pos }));
+        }
+        return;
+    }
+    if let Ok(v) = app.session.execute("mask.new", json!({"layer": lid.0, "vertices": [lp]}))
+        && let Some(mask) = v["mask"].as_u64()
+    {
+        ui.data_mut(|d| {
+            d.insert_temp(pen_id(), (lid, mask));
+            d.insert_temp(gid, Gesture::Pen { layer: lid, mask, index: 0, vertex: lp, inv, press: pos });
+        });
+    }
+}
+
 /// Topmost layer under a comp point (selects it; shift toggles). Returns the hit layer.
 fn pick(app: &mut EffectcraftApp, ectx: &EvalCtx, cpt: [f64; 2], toggle: bool) -> Option<LayerId> {
     let hit = ectx
@@ -851,7 +1057,7 @@ fn bottom_bar(app: &mut EffectcraftApp, ui: &mut egui::Ui, bar: Rect, zoom: f32,
         app.ui.viewer.res = Resolution::ALL[i];
     }
     x = r.max.x + 6.0;
-    if tog(ui, &mut app.auto, &mut x, Icon::Region, false, "roi", "Region of Interest") {}
+    let _ = tog(ui, &mut app.auto, &mut x, Icon::Region, false, "roi", "Region of Interest");
     if tog(ui, &mut app.auto, &mut x, Icon::Checker, app.ui.viewer.transparency_grid, "transparency", "Toggle Transparency Grid") {
         app.ui.viewer.transparency_grid = !app.ui.viewer.transparency_grid;
     }

crates/ui-egui/src/state.rs

@@ -249,6 +249,28 @@ pub struct TimelineState {
     pub open_groups: BTreeSet<u64>,
     /// "Reveal" filter: only show these property match ids (P/S/R/T/A…) — empty = normal.
     pub reveal: Vec<String>,
+    /// Graph Editor: `value` or `speed` graph.
+    #[serde(default = "value_graph")]
+    pub graph_mode: String,
+    /// Show only the selected properties (else every animated property of the selected layers).
+    #[serde(default = "yes")]
+    pub graph_show_selected: bool,
+    /// Auto-zoom the graph height to the visible curves.
+    #[serde(default = "yes")]
+    pub graph_auto_zoom: bool,
+    /// Manual graph value range (when auto-zoom is off).
+    #[serde(default)]
+    pub graph_range: Option<(f64, f64)>,
+    /// Properties whose inline expression editor is collapsed.
+    #[serde(default)]
+    pub expr_closed: BTreeSet<u64>,
+}
+
+fn value_graph() -> String {
+    "value".into()
+}
+fn yes() -> bool {
+    true
 }
 
 impl Default for TimelineState {
@@ -258,12 +280,17 @@ impl Default for TimelineState {
             pps: None,
             scroll_y: 0.0,
             columns_w: 560.0,
-            show_modes: true,
+            show_modes: false,
             graph_editor: false,
             search: String::new(),
             open_layers: BTreeSet::new(),
             open_groups: BTreeSet::new(),
             reveal: vec![],
+            graph_mode: value_graph(),
+            graph_show_selected: true,
+            graph_auto_zoom: true,
+            graph_range: None,
+            expr_closed: BTreeSet::new(),
         }
     }
 }