diff --git a/ASSETS.md b/ASSETS.md index 4684a39f..69ffc8a0 100644 --- a/ASSETS.md +++ b/ASSETS.md @@ -89,6 +89,8 @@ Generated-in-code art is original and has no file to list. This covers the defau | `assets/icons/dc-appearance.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | | `assets/icons/dc-arc.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | | `assets/icons/dc-arrow-down.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | +| `assets/icons/dc-arrow-extend.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | +| `assets/icons/dc-arrow-tip.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | | `assets/icons/dc-arrow-up.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | | `assets/icons/dc-artboard-options.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | | `assets/icons/dc-artboards.svg` | VectorCraft contributors | Original work, drawn for VectorCraft | MIT OR Apache-2.0 | | diff --git a/assets/icons/dc-arrow-extend.svg b/assets/icons/dc-arrow-extend.svg new file mode 100644 index 00000000..fd1092ba --- /dev/null +++ b/assets/icons/dc-arrow-extend.svg @@ -0,0 +1 @@ + diff --git a/assets/icons/dc-arrow-tip.svg b/assets/icons/dc-arrow-tip.svg new file mode 100644 index 00000000..a83f67a6 --- /dev/null +++ b/assets/icons/dc-arrow-tip.svg @@ -0,0 +1 @@ + diff --git a/crates/doc/src/appearance.rs b/crates/doc/src/appearance.rs index 69597c83..b72f79c0 100644 --- a/crates/doc/src/appearance.rs +++ b/crates/doc/src/appearance.rs @@ -77,12 +77,34 @@ impl Arrowhead { ]; } +/// Where an arrowhead sits relative to the end of its path. In both modes the stroke stops under +/// the head, so the line never shows through a hollow head or past its tip. +#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Hash, Serialize, Deserialize)] +pub enum ArrowAlign { + /// The tip extends past the end point (the path keeps its length). + #[default] + Extend, + /// The tip sits on the end point (the stroke is shortened by the head). + Tip, +} + /// Variable-width profile: (position 0..1 along the path, left width factor, right width factor). #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)] pub struct WidthProfile { pub points: Vec<(f64, f64, f64)>, } +/// A built-in width profile (the Stroke panel's Profile list). +#[derive(Clone, Copy, Debug, PartialEq)] +pub struct ProfilePreset { + /// Stable id used by `stroke.set {profile}`. + pub id: &'static str, + /// Menu label. + pub label: &'static str, + /// (t, left, right) width points. + pub points: &'static [(f64, f64, f64)], +} + impl WidthProfile { /// Width factor at `t` (average of both sides), linear between points. pub fn at(&self, t: f64) -> (f64, f64) { @@ -102,15 +124,34 @@ impl WidthProfile { let l = p.last().unwrap(); (l.1, l.2) } - /// Illustrator's "Width Profile 1" (lens shape) analogue. + /// The built-in profiles, in menu order. "uniform" is the plain stroke (no profile). + pub const PRESETS: [ProfilePreset; 4] = [ + ProfilePreset { id: "uniform", label: "Uniform", points: &[(0.0, 1.0, 1.0), (1.0, 1.0, 1.0)] }, + ProfilePreset { id: "lens", label: "Lens", points: &[(0.0, 0.0, 0.0), (0.5, 1.0, 1.0), (1.0, 0.0, 0.0)] }, + ProfilePreset { id: "taperStart", label: "Taper Start", points: &[(0.0, 0.0, 0.0), (1.0, 1.0, 1.0)] }, + ProfilePreset { id: "taperEnd", label: "Taper End", points: &[(0.0, 1.0, 1.0), (1.0, 0.0, 0.0)] }, + ]; + /// The built-in profile with this id. + pub fn preset(id: &str) -> Option { + Self::PRESETS.iter().find(|p| p.id == id).map(|p| Self { points: p.points.to_vec() }) + } + /// The id of the built-in profile these points match, if any. + pub fn preset_id(&self) -> Option<&'static str> { + Self::PRESETS.iter().find(|p| p.points == self.points.as_slice()).map(|p| p.id) + } + /// The id of a stroke's profile: "uniform" without one, "custom" when it matches no preset. + pub fn id_of(p: Option<&Self>) -> &'static str { + p.map_or(Some("uniform"), Self::preset_id).unwrap_or("custom") + } + /// The lens profile (thin ends, full width in the middle). pub fn lens() -> Self { - Self { points: vec![(0.0, 0.0, 0.0), (0.5, 1.0, 1.0), (1.0, 0.0, 0.0)] } + Self::preset("lens").expect("built-in") } pub fn taper_end() -> Self { - Self { points: vec![(0.0, 1.0, 1.0), (1.0, 0.0, 0.0)] } + Self::preset("taperEnd").expect("built-in") } pub fn taper_start() -> Self { - Self { points: vec![(0.0, 0.0, 0.0), (1.0, 1.0, 1.0)] } + Self::preset("taperStart").expect("built-in") } } @@ -186,6 +227,9 @@ pub struct StrokeLayer { pub visible: bool, #[serde(default, skip_serializing_if = "Vec::is_empty")] pub effects: Vec, + /// Arrowhead placement at both ends. + #[serde(default, skip_serializing_if = "crate::skip::is_default")] + pub arrow_align: ArrowAlign, } fn ten() -> f64 { @@ -220,8 +264,21 @@ impl StrokeLayer { blend: BlendMode::Normal, visible: true, effects: vec![], + arrow_align: ArrowAlign::Extend, } } + /// Weight of the start (`end == false`) or end arrowhead: stroke weight × its scale, at least + /// a quarter point. A head of weight `hw` is `4·hw` long and wide. + pub fn arrow_weight(&self, end: bool) -> f64 { + let pct = if end { self.arrow_scale.1 } else { self.arrow_scale.0 }; + (self.width * pct / 100.0).max(0.25) + } + /// How far the arrowheads can reach from the path's end points (0 without heads): the + /// head's diagonal, or with [`ArrowAlign::Extend`] its length plus the cap past the end. + pub fn arrow_reach(&self) -> f64 { + let reach = |head: Option, end: bool| head.map_or(0.0, |_| 4.5 * self.arrow_weight(end) + self.width / 2.0); + reach(self.start_arrow, false).max(reach(self.end_arrow, true)) + } /// The box an unplaced gradient on this stroke fits to (see [`stroke_paint_bounds`]). pub fn paint_bounds(&self, geometric: vectorcraft_geom::Rect) -> vectorcraft_geom::Rect { stroke_paint_bounds(geometric, self.width) @@ -313,11 +370,14 @@ impl Appearance { self.items .iter() .filter_map(|i| match i { - AppearanceItem::Stroke(s) if s.visible && !s.paint.is_none() => Some(match s.align { - StrokeAlign::Center => s.width / 2.0 * if s.join == LineJoin::Miter { s.miter_limit.min(4.0) } else { 1.0 }, - StrokeAlign::Outside => s.width, - StrokeAlign::Inside => 0.0, - }), + AppearanceItem::Stroke(s) if s.visible && !s.paint.is_none() => Some( + match s.align { + StrokeAlign::Center => s.width / 2.0 * if s.join == LineJoin::Miter { s.miter_limit.min(4.0) } else { 1.0 }, + StrokeAlign::Outside => s.width, + StrokeAlign::Inside => 0.0, + } + .max(s.arrow_reach()), + ), _ => None, }) .fold(0.0, f64::max) @@ -414,6 +474,48 @@ mod tests { assert_eq!(p.at(2.0), (0.0, 0.0)); } + #[test] + fn profile_presets_round_trip_their_ids() { + for p in WidthProfile::PRESETS { + let prof = WidthProfile::preset(p.id).unwrap(); + assert_eq!(prof.preset_id(), Some(p.id)); + assert_eq!(WidthProfile::id_of(Some(&prof)), p.id); + } + assert_eq!(WidthProfile::id_of(None), "uniform"); + assert_eq!(WidthProfile::id_of(Some(&WidthProfile { points: vec![(0.0, 0.3, 0.3)] })), "custom"); + assert!(WidthProfile::preset("nope").is_none()); + assert_eq!(WidthProfile::lens().points, vec![(0.0, 0.0, 0.0), (0.5, 1.0, 1.0), (1.0, 0.0, 0.0)]); + } + + #[test] + fn arrow_align_defaults_to_extend_and_round_trips() { + let mut st = StrokeLayer::new(Paint::solid(Color::BLACK), 2.0); + assert_eq!(st.arrow_align, ArrowAlign::Extend); + // The default is not written, so older readers see the same JSON as before. + assert!(!serde_json::to_string(&st).unwrap().contains("arrow_align")); + let old: StrokeLayer = serde_json::from_str(r#"{"paint":{"type":"none"},"width":2.0}"#).unwrap(); + assert_eq!(old.arrow_align, ArrowAlign::Extend); + st.arrow_align = ArrowAlign::Tip; + let back: StrokeLayer = serde_json::from_str(&serde_json::to_string(&st).unwrap()).unwrap(); + assert_eq!(back, st); + } + + #[test] + fn outset_covers_arrowheads() { + let mut a = Appearance::basic(Paint::None, Paint::solid(Color::BLACK), 4.0); + a.stroke_mut().unwrap().join = LineJoin::Round; + assert_eq!(a.outset(), 2.0); + let st = a.stroke_mut().unwrap(); + st.end_arrow = Some(Arrowhead::Triangle); + st.arrow_scale = (100.0, 200.0); + assert_eq!(st.arrow_weight(false), 4.0); + assert_eq!(st.arrow_weight(true), 8.0); + // A 32 pt head whose tip sits up to its length (plus the cap) past the end point. + assert_eq!(a.outset(), 4.5 * 8.0 + 2.0); + a.stroke_mut().unwrap().width = 0.01; + assert_eq!(a.stroke().unwrap().arrow_weight(true), 0.25, "heads keep a minimum size"); + } + #[test] fn outset_depends_on_align() { let mut a = Appearance::basic(Paint::None, Paint::solid(Color::BLACK), 10.0); diff --git a/crates/doc/src/lib.rs b/crates/doc/src/lib.rs index 4378dd75..79f044ab 100644 --- a/crates/doc/src/lib.rs +++ b/crates/doc/src/lib.rs @@ -31,7 +31,10 @@ pub(crate) mod skip { } } -pub use appearance::{Appearance, AppearanceItem, Arrowhead, Dash, Effect, FillLayer, LineCap, LineJoin, StrokeAlign, StrokeLayer, WidthProfile}; +pub use appearance::{ + Appearance, AppearanceItem, ArrowAlign, Arrowhead, Dash, Effect, FillLayer, LineCap, LineJoin, ProfilePreset, StrokeAlign, StrokeLayer, + WidthProfile, +}; pub use graph::{GraphKind, GraphSpec}; pub use hit::{Hit, HitKind}; pub use live::{BlendOrientation, BlendSpacing, BlendSpec, EnvelopeKind, GradientMesh, MeshPoint}; diff --git a/crates/effects/src/lib.rs b/crates/effects/src/lib.rs index 17c4911f..3268d948 100644 --- a/crates/effects/src/lib.rs +++ b/crates/effects/src/lib.rs @@ -8,6 +8,8 @@ //! - **Raster effects** (Drop Shadow, Inner/Outer Glow, Feather, Gaussian Blur) are described by //! [`raster_effects`] and painted by the renderer; [`outset`] says how far they reach beyond //! the geometry. +//! - **Stroke geometry** ([`stroke`]): arrowheads, dash patterns and width profiles, shared by the +//! renderer, the exporters and Outline Stroke. //! - [`effect_catalog`] lists every effect with its menu path, parameter documentation and the //! defaults of Illustrator's dialogs. Missing parameters always fall back to those defaults. //! @@ -19,6 +21,7 @@ mod bake; mod distort; mod group; mod raster; +pub mod stroke; mod stylize; mod util; mod warp; diff --git a/crates/effects/src/stroke.rs b/crates/effects/src/stroke.rs new file mode 100644 index 00000000..f57f949f --- /dev/null +++ b/crates/effects/src/stroke.rs @@ -0,0 +1,182 @@ +//! Stroke geometry shared by the canvas, the PDF/SVG exporters and Outline Stroke, so every +//! consumer paints the same shapes: +//! +//! - [`stroke_pieces`]: the centre line (trimmed under the arrowheads) and the arrowheads as +//! filled outlines (hollow kinds are rings), placed by [`ArrowAlign`](vectorcraft_doc::ArrowAlign); +//! - [`dash`]: the dash pattern; zero-length dashes become [`Dot`]s that a round or projecting cap +//! turns into discs or squares ([`dot_outline`]); +//! - [`width_outline`]: variable-width (profile) strokes; +//! - [`line_outline`]: the line part of a stroke as one filled outline (profile, dashes, dots, +//! caps and joins). + +mod arrow; +mod dash; +mod width; + +use std::borrow::Cow; + +use kurbo::{BezPath, ParamCurve, ParamCurveDeriv, PathEl, PathSeg, Vec2}; +use vectorcraft_doc::{LineCap, LineJoin, StrokeAlign, StrokeLayer}; + +pub use arrow::Arrow; +pub use dash::{Dashed, Dot, dash, dot_outline}; +pub use width::width_outline; + +/// Arc-length accuracy for dashing and trimming (document points). +const ARCLEN_ACCURACY: f64 = 1e-6; + +/// The geometry one stroke paints, in the coordinate space of its path. +#[derive(Clone, Debug)] +pub struct StrokePieces<'a> { + /// The centre line to stroke: the path with its ends trimmed under the arrowheads (borrowed + /// when nothing is trimmed). Empty when the heads cover the whole path. + pub line: Cow<'a, BezPath>, + /// The arrowheads, start first. Closed ends get none. + pub heads: Vec, +} + +/// The centre line and arrowheads of stroke `st` along `bp`. +pub fn stroke_pieces<'a>(bp: &'a BezPath, st: &StrokeLayer) -> StrokePieces<'a> { + if st.start_arrow.is_none() && st.end_arrow.is_none() { + return StrokePieces { line: Cow::Borrowed(bp), heads: vec![] }; + } + arrow::pieces(bp, st) +} + +/// Does `bp` end with a `ClosePath`? +pub fn is_closed(bp: &BezPath) -> bool { + bp.elements().last().is_some_and(|e| matches!(e, PathEl::ClosePath)) +} + +/// The width actually stroked: inside/outside strokes of closed paths are drawn twice as wide +/// and clipped to one side; open paths always stroke centred. +pub fn aligned_width(st: &StrokeLayer, closed: bool) -> f64 { + match st.align { + StrokeAlign::Inside | StrokeAlign::Outside if closed => st.width * 2.0, + _ => st.width, + } +} + +/// How far a cap reaches past the end of a stroke of `width`. +pub fn cap_extent(cap: LineCap, width: f64) -> f64 { + match cap { + LineCap::Butt => 0.0, + LineCap::Round | LineCap::Square => width / 2.0, + } +} + +/// The stroke style (cap, join, miter limit) of `st` at `width`, without dashes. +pub fn style(st: &StrokeLayer, width: f64) -> kurbo::Stroke { + kurbo::Stroke::new(width) + .with_join(match st.join { + LineJoin::Miter => kurbo::Join::Miter, + LineJoin::Round => kurbo::Join::Round, + LineJoin::Bevel => kurbo::Join::Bevel, + }) + .with_caps(match st.cap { + LineCap::Butt => kurbo::Cap::Butt, + LineCap::Round => kurbo::Cap::Round, + LineCap::Square => kurbo::Cap::Square, + }) + .with_miter_limit(st.miter_limit) +} + +/// Does the dash pattern of `st` draw anything other than a solid line? +pub fn is_dashed(st: &StrokeLayer) -> bool { + st.dash.as_ref().is_some_and(|d| d.pattern.iter().any(|v| *v > 0.0)) +} + +/// The filled outline of the line part of `st` along `line` (usually [`StrokePieces::line`]) at +/// `width` (see [`aligned_width`]), flattened/fitted to `tol`: the width profile, or the dash +/// pattern with its dots, with the stroke's caps and joins. Fill it with the non-zero rule. +/// Arrowheads are not included. +pub fn line_outline(line: &BezPath, st: &StrokeLayer, width: f64, tol: f64) -> BezPath { + if line.elements().is_empty() || width <= 0.0 || !width.is_finite() { + return BezPath::new(); + } + let tol = tol.max(1e-4); + if let Some(profile) = st.profile.as_ref().filter(|_| !is_dashed(st)) { + return width_outline(line, width, profile, st.cap, tol); + } + let style = style(st, width); + match st.dash.as_ref().and_then(|d| dash(line, d)) { + Some(d) => { + let mut out = kurbo::stroke(d.path.iter(), &style, &kurbo::StrokeOpts::default(), tol); + out.extend(dot_outline(&d.dots, width, st.cap, tol).iter()); + out + } + None => kurbo::stroke(line.iter(), &style, &kurbo::StrokeOpts::default(), tol), + } +} + +/// Unit tangent of `s` at `t`, robust at ends where control points coincide with the end point. +pub(crate) fn tangent(s: &PathSeg, t: f64) -> Vec2 { + let d = match s { + PathSeg::Line(l) => l.p1 - l.p0, + PathSeg::Quad(q) => { + let v = q.deriv().eval(t).to_vec2(); + if v.hypot() > 1e-9 { v } else { q.p2 - q.p0 } + } + PathSeg::Cubic(c) => { + let v = c.deriv().eval(t).to_vec2(); + if v.hypot() > 1e-9 { + v + } else if t < 0.5 { + // The first control point that differs from the start gives the direction. + [c.p2, c.p3].into_iter().map(|p| p - c.p0).find(|v| v.hypot() > 1e-9).unwrap_or_default() + } else { + [c.p1, c.p0].into_iter().map(|p| c.p3 - p).find(|v| v.hypot() > 1e-9).unwrap_or_default() + } + } + }; + unit(d) +} + +/// `v` normalised, or +x when it has no length. +pub(crate) fn unit(v: Vec2) -> Vec2 { + let h = v.hypot(); + if h > 1e-12 { v / h } else { Vec2::new(1.0, 0.0) } +} + +/// Append `seg` to `out` (which must already have a current point at its start). +pub(crate) fn push_seg(out: &mut BezPath, seg: &PathSeg) { + match seg { + PathSeg::Line(l) => out.line_to(l.p1), + PathSeg::Quad(q) => out.quad_to(q.p1, q.p2), + PathSeg::Cubic(c) => out.curve_to(c.p1, c.p2, c.p3), + } +} + +/// Element ranges of the subpaths of `bp` (each with whether it is closed). +pub(crate) fn subpaths(bp: &BezPath) -> Vec<(std::ops::Range, bool)> { + let els = bp.elements(); + let mut out = vec![]; + let mut start = 0; + for (i, el) in els.iter().enumerate() { + match el { + PathEl::MoveTo(_) if i > start => { + out.push((start..i, false)); + start = i; + } + PathEl::ClosePath => { + out.push((start..i + 1, true)); + start = i + 1; + } + _ => {} + } + } + if start < els.len() { + out.push((start..els.len(), false)); + } + // A lone MoveTo (or a MoveTo straight after a ClosePath) draws nothing. + out.retain(|(r, _)| r.len() > 1); + out +} + +/// The segments of one subpath (`els` starts with its MoveTo; a ClosePath adds the closing line). +pub(crate) fn segments(els: &[PathEl]) -> Vec { + kurbo::segments(els.iter().copied()).collect() +} + +#[cfg(test)] +mod tests; diff --git a/crates/effects/src/stroke/arrow.rs b/crates/effects/src/stroke/arrow.rs new file mode 100644 index 00000000..080ddeb3 --- /dev/null +++ b/crates/effects/src/stroke/arrow.rs @@ -0,0 +1,257 @@ +//! Arrowheads. A head of weight `hw` (stroke weight × scale) is `4·hw` long and `4·hw` wide. +//! Hollow kinds are rings (`hw/2` walls) or, for the open arrow, a chevron with `hw` arms. The +//! stroke ends under the head at the head's *inset* from the tip: halfway into solid heads, in +//! the back wall of hollow ones (with the cap kept out of the hole) and at the chevron's inner +//! corner. With [`ArrowAlign::Tip`] the tip sits on the end point and the stroke is shortened by +//! the inset; with [`ArrowAlign::Extend`] the path keeps its length and the tip sits the inset +//! past the end point. + +use std::borrow::Cow; + +use kurbo::{BezPath, ParamCurve, ParamCurveArclen, PathSeg, Point, Shape, Vec2}; +use vectorcraft_doc::{ArrowAlign, Arrowhead, StrokeLayer}; + +use super::{ARCLEN_ACCURACY, StrokePieces, cap_extent, push_seg, segments, subpaths, tangent, unit}; + +/// One arrowhead. +#[derive(Clone, Debug, PartialEq)] +pub struct Arrow { + pub kind: Arrowhead, + /// The filled outline (non-zero rule; hollow kinds are rings). + pub outline: BezPath, + pub tip: Point, + /// Unit direction the head points in. + pub dir: Vec2, + /// Distance from the tip back to where the stroke ends under the head. + pub inset: f64, +} + +/// [`super::stroke_pieces`] for a stroke with at least one arrowhead. +pub(super) fn pieces<'a>(bp: &'a BezPath, st: &StrokeLayer) -> StrokePieces<'a> { + let subs = subpaths(bp); + let els = bp.elements(); + // Heads go on the start of the first subpath and the end of the last one, when open. + let first = subs.first().filter(|s| !s.1).map(|s| s.0.clone()); + let last = subs.last().filter(|s| !s.1).map(|s| s.0.clone()); + let cap = cap_extent(st.cap, st.width); + let (hw0, hw1) = (st.arrow_weight(false), st.arrow_weight(true)); + let start = st.start_arrow.zip(first).map(|(k, r)| (k, r, inset(k, hw0, cap))); + let end = st.end_arrow.zip(last).map(|(k, r)| (k, r, inset(k, hw1, cap))); + if start.is_none() && end.is_none() { + return StrokePieces { line: Cow::Borrowed(bp), heads: vec![] }; + } + let tip_mode = st.arrow_align == ArrowAlign::Tip; + let mut heads = vec![]; + // Trims per subpath index (start, end), applied in tip mode only. + let mut trims: Vec<(f64, f64)> = vec![(0.0, 0.0); subs.len()]; + let mut place = |kind: Arrowhead, range: std::ops::Range, at_start: bool, inset: f64, hw: f64| { + let segs = segments(&els[range]); + let (end_pt, outward) = end_of(&segs, at_start); + let (tip, dir) = if tip_mode { + // Point along the chord from where the stroke now ends to the end point. + let dir = cut_point(&segs, at_start, inset).map(|p| end_pt - p).filter(|v| v.hypot() > 1e-9).map(unit).unwrap_or(outward); + (end_pt, dir) + } else { + (end_pt + outward * inset, outward) + }; + heads.push(Arrow { kind, outline: shape(kind, tip, dir, hw), tip, dir, inset }); + }; + if let Some((k, r, i)) = start { + place(k, r, true, i, hw0); + if tip_mode { + trims[0].0 = i; + } + } + if let Some((k, r, i)) = end { + place(k, r, false, i, hw1); + if tip_mode { + trims[subs.len() - 1].1 = i; + } + } + if !tip_mode { + return StrokePieces { line: Cow::Borrowed(bp), heads }; + } + let mut line = BezPath::new(); + for ((range, _), &(s0, s1)) in subs.iter().zip(&trims) { + if s0 == 0.0 && s1 == 0.0 { + line.extend(els[range.clone()].iter().copied()); + continue; + } + // Only open subpaths get heads, so a trimmed subpath stays open. + let segs = trim(&segments(&els[range.clone()]), s0, s1); + if let Some(first) = segs.first() { + line.move_to(first.start()); + for s in &segs { + push_seg(&mut line, s); + } + } + } + StrokePieces { line: Cow::Owned(line), heads } +} + +/// The end point of a subpath and the unit direction pointing out of it there. +fn end_of(segs: &[PathSeg], at_start: bool) -> (Point, Vec2) { + let long = |s: &&PathSeg| s.arclen(ARCLEN_ACCURACY) > 1e-9; + if at_start { + let p = segs.first().map_or(Point::ORIGIN, |s| s.start()); + let d = segs.iter().find(long).map_or(Vec2::new(-1.0, 0.0), |s| -tangent(s, 0.0)); + (p, d) + } else { + let p = segs.last().map_or(Point::ORIGIN, |s| s.end()); + let d = segs.iter().rev().find(long).map_or(Vec2::new(1.0, 0.0), |s| tangent(s, 1.0)); + (p, d) + } +} + +/// The point `dist` along the subpath from its start (or back from its end), if it is that long. +fn cut_point(segs: &[PathSeg], from_start: bool, dist: f64) -> Option { + let (i, t) = if from_start { cut_from_start(segs, dist)? } else { cut_from_end(segs, dist)? }; + Some(segs[i].eval(t)) +} + +/// (segment, parameter) at arc length `dist` from the start. +fn cut_from_start(segs: &[PathSeg], dist: f64) -> Option<(usize, f64)> { + let mut acc = 0.0; + for (i, s) in segs.iter().enumerate() { + let len = s.arclen(ARCLEN_ACCURACY); + if acc + len >= dist { + return Some((i, if len > 0.0 { s.inv_arclen(dist - acc, ARCLEN_ACCURACY) } else { 0.0 })); + } + acc += len; + } + None +} + +/// (segment, parameter) at arc length `dist` back from the end. +fn cut_from_end(segs: &[PathSeg], dist: f64) -> Option<(usize, f64)> { + let mut acc = 0.0; + for (i, s) in segs.iter().enumerate().rev() { + let len = s.arclen(ARCLEN_ACCURACY); + if acc + len >= dist { + return Some((i, if len > 0.0 { s.inv_arclen(len - (dist - acc), ARCLEN_ACCURACY) } else { 1.0 })); + } + acc += len; + } + None +} + +/// The segments with `s0` of arc length removed from the start and `s1` from the end (empty when +/// nothing is left). +fn trim(segs: &[PathSeg], s0: f64, s1: f64) -> Vec { + let (Some((i0, t0)), Some((i1, t1))) = (cut_from_start(segs, s0), cut_from_end(segs, s1)) else { return vec![] }; + if (i0, t0) >= (i1, t1) { + return vec![]; + } + if i0 == i1 { + return vec![segs[i0].subsegment(t0..t1)]; + } + let mut out = Vec::with_capacity(i1 - i0 + 1); + out.push(segs[i0].subsegment(t0..1.0)); + out.extend_from_slice(&segs[i0 + 1..i1]); + out.push(segs[i1].subsegment(0.0..t1)); + out +} + +/// Head length (and width) for weight `hw`. +fn len(hw: f64) -> f64 { + 4.0 * hw +} +/// Wall of the hollow ring heads. +fn ring(hw: f64) -> f64 { + 0.5 * hw +} +/// Arm thickness of the open arrow. +fn arm(hw: f64) -> f64 { + hw +} +/// Thickness of the bar. +fn bar(hw: f64) -> f64 { + 0.75 * hw +} +/// Where the notch of the (open) arrow sits, as a fraction of the length. +const NOTCH: f64 = 0.7; + +/// Distance from the tip where the stroke ends, for a stroke whose cap reaches `cap` past its end. +fn inset(kind: Arrowhead, hw: f64, cap: f64) -> f64 { + let l = len(hw); + // Solid heads: halfway in, far enough that the cap stays behind the tip. + let solid = |back: f64| (back / 2.0).max(cap); + // Hollow heads: in the back wall, with the cap kept out of the hole. + let hollow = |back: f64| (back - ring(hw) / 2.0).max(back - ring(hw) + cap); + match kind { + Arrowhead::Triangle | Arrowhead::Circle | Arrowhead::Square | Arrowhead::Diamond => solid(l), + Arrowhead::Arrow => solid(NOTCH * l), + Arrowhead::Bar => solid(bar(hw)), + Arrowhead::TriangleOpen | Arrowhead::CircleOpen | Arrowhead::SquareOpen => hollow(l), + // The inner corner of the chevron: arm / sin(half angle). + Arrowhead::ArrowOpen => (arm(hw) * (l * l + l * l / 4.0).sqrt() / (l / 2.0)).max(cap), + } +} + +/// Outline of a `kind` head of weight `hw` with its tip at `tip`, pointing along `dir`. +fn shape(kind: Arrowhead, tip: Point, dir: Vec2, hw: f64) -> BezPath { + let n = Vec2::new(-dir.y, dir.x); + let l = len(hw); + let half = l / 2.0; + let base = tip - dir * l; + let mut p = BezPath::new(); + let triangle = [tip, base + n * half, base - n * half]; + let square = [tip + n * half, base + n * half, base - n * half, tip - n * half]; + let centre = tip - dir * half; + match kind { + Arrowhead::Triangle => polygon(&mut p, &triangle), + Arrowhead::TriangleOpen => ring_polygon(&mut p, &triangle, ring(hw)), + Arrowhead::Arrow => polygon(&mut p, &[tip, base + n * half, tip - dir * (NOTCH * l), base - n * half]), + Arrowhead::ArrowOpen => { + // Arms of thickness `arm` from the tip to the base corners, cut square at their ends. + let t = arm(hw); + let (a, b) = (base + n * half, base - n * half); + let (ua, ub) = (unit(a - tip), unit(b - tip)); + // Inward (towards the axis) normals of the two arms. + let (na, nb) = (Vec2::new(-ua.y, ua.x), Vec2::new(ub.y, -ub.x)); + let inner = tip - dir * (t * (a - tip).hypot() / half); + polygon(&mut p, &[tip, a, a + na * t, inner, b + nb * t, b]); + } + Arrowhead::Circle => p.extend(kurbo::Circle::new(centre, half).path_elements(0.01)), + Arrowhead::CircleOpen => { + p.extend(kurbo::Circle::new(centre, half).path_elements(0.01)); + p.extend(kurbo::Circle::new(centre, half - ring(hw)).to_path(0.01).reverse_subpaths()); + } + Arrowhead::Square => polygon(&mut p, &square), + Arrowhead::SquareOpen => ring_polygon(&mut p, &square, ring(hw)), + Arrowhead::Diamond => polygon(&mut p, &[tip, centre + n * half, base, centre - n * half]), + Arrowhead::Bar => { + let t = bar(hw); + polygon(&mut p, &[tip + n * half, tip + n * half - dir * t, tip - n * half - dir * t, tip - n * half]); + } + } + p +} + +fn polygon(p: &mut BezPath, pts: &[Point]) { + let Some((first, rest)) = pts.split_first() else { return }; + p.move_to(*first); + for q in rest { + p.line_to(*q); + } + p.close_path(); +} + +/// A convex polygon with a hole: the polygon inset by `wall`, wound the other way. +fn ring_polygon(p: &mut BezPath, pts: &[Point], wall: f64) { + polygon(p, pts); + let n = pts.len(); + // Signed area: which side of each edge is inside. + let area: f64 = (0..n).map(|i| pts[i].to_vec2().cross(pts[(i + 1) % n].to_vec2())).sum(); + let inward = |e: Vec2| if area > 0.0 { Vec2::new(-e.y, e.x) } else { Vec2::new(e.y, -e.x) }; + let inner: Vec = (0..n) + .map(|i| { + let (prev, cur, next) = (pts[(i + n - 1) % n], pts[i], pts[(i + 1) % n]); + let (n1, n2) = (inward(unit(cur - prev)), inward(unit(next - cur))); + // The corner where both edges, moved in by `wall`, meet. + cur + (n1 + n2) * (wall / (1.0 + n1.dot(n2))) + }) + .rev() + .collect(); + polygon(p, &inner); +} diff --git a/crates/effects/src/stroke/dash.rs b/crates/effects/src/stroke/dash.rs new file mode 100644 index 00000000..a5d8ce00 --- /dev/null +++ b/crates/effects/src/stroke/dash.rs @@ -0,0 +1,191 @@ +//! Dash patterns. Dashes follow the path's arc length, restart on every subpath and join across +//! the start of a closed subpath. A dash of zero length is a [`Dot`]: with a round cap it paints +//! a disc, with a projecting cap a square turned along the path, with a butt cap nothing. + +use kurbo::{BezPath, ParamCurve, ParamCurveArclen, PathSeg, Point, Shape, Vec2}; +use vectorcraft_doc::{Dash, LineCap}; + +use super::{ARCLEN_ACCURACY, push_seg, segments, subpaths, tangent}; + +/// More dashes than this (a tiny pattern on a long path) draws the line solid instead. +const MAX_DASHES: f64 = 200_000.0; +/// A pattern whose longest entry is shorter than this can't advance along the path (each entry +/// ends within the generator's tolerance of where it starts), so it draws the line solid. +const MIN_ENTRY: f64 = 1e-6; + +/// A zero-length dash: where it sits and the path's direction there. +#[derive(Clone, Copy, Debug, PartialEq)] +pub struct Dot { + pub at: Point, + pub dir: Vec2, +} + +/// A dashed path: the dashes (open subpaths to stroke without a dash pattern) and the dots. +#[derive(Clone, Debug, Default)] +pub struct Dashed { + pub path: BezPath, + pub dots: Vec, +} + +/// Apply dash pattern `d` to `bp`. `None` when the pattern has no positive length (the line is +/// solid) or is too fine to draw (then the line is drawn solid too). +pub fn dash(bp: &BezPath, d: &Dash) -> Option { + if d.pattern.iter().any(|v| !v.is_finite()) || !d.offset.is_finite() { + return None; + } + let mut pat: Vec = d.pattern.iter().map(|v| v.max(0.0)).collect(); + if !pat.iter().any(|v| *v > MIN_ENTRY) { + return None; + } + // An odd pattern repeats with dashes and gaps swapped (as in SVG and PDF). + if pat.len() % 2 == 1 { + pat.extend_from_within(..); + } + let period: f64 = pat.iter().sum(); + let subs: Vec<(Vec, bool)> = subpaths(bp).into_iter().map(|(r, closed)| (segments(&bp.elements()[r]), closed)).collect(); + let lens: Vec> = subs.iter().map(|(segs, _)| segs.iter().map(|s| s.arclen(ARCLEN_ACCURACY)).collect()).collect(); + let total: f64 = lens.iter().flatten().sum(); + if total / period * pat.len() as f64 > MAX_DASHES { + return None; + } + // Where the pattern starts: `offset` into it. + let mut off = d.offset.rem_euclid(period); + let mut ix0 = 0; + while off > pat[ix0] { + off -= pat[ix0]; + ix0 = (ix0 + 1) % pat.len(); + } + let phase = Phase { ix: ix0, rem: pat[ix0] - off, on: ix0 % 2 == 0 }; + let mut out = Dashed::default(); + for ((segs, closed), lens) in subs.iter().zip(&lens) { + dash_subpath(&mut out, segs, lens, *closed, &pat, phase); + } + Some(out) +} + +/// Position in the pattern: entry index, length left in it, and whether it is a dash. +#[derive(Clone, Copy)] +struct Phase { + ix: usize, + rem: f64, + on: bool, +} + +fn dash_subpath(out: &mut Dashed, segs: &[PathSeg], lens: &[f64], closed: bool, pat: &[f64], mut ph: Phase) { + const EPS: f64 = 1e-9; + let first_dot = out.dots.len(); + let starts_on = ph.on && ph.rem > 0.0; + let mut dashes: Vec> = vec![]; + let mut cur: Vec = vec![]; + let mut cuts = 0; + for (seg, &len) in segs.iter().zip(lens) { + let mut s = 0.0; + loop { + let left = len - s; + if ph.rem > left + EPS { + if ph.on && left > EPS { + cur.push(sub(seg, len, s, len)); + } + ph.rem -= left; + break; + } + let end = (s + ph.rem).min(len); + if ph.on { + if pat[ph.ix] > 0.0 { + if end > s { + cur.push(sub(seg, len, s, end)); + } + if !cur.is_empty() { + dashes.push(std::mem::take(&mut cur)); + } + } else { + let t = param(seg, len, end); + out.dots.push(Dot { at: seg.eval(t), dir: tangent(seg, t) }); + } + } + cuts += 1; + s = end; + ph.ix = (ph.ix + 1) % pat.len(); + ph.rem = pat[ph.ix]; + ph.on = !ph.on; + } + } + let ends_on = !cur.is_empty(); + if ends_on { + dashes.push(cur); + } + if closed { + if cuts == 0 && ends_on { + // One dash all the way round: keep it closed so the start gets a join, not caps. + let segs = dashes.pop().unwrap_or_default(); + write(&mut out.path, &segs); + out.path.close_path(); + return; + } + if starts_on && ends_on && dashes.len() > 1 { + // The dash running through the start point is one dash. + let mut last = dashes.pop().unwrap_or_default(); + last.append(&mut dashes[0]); + dashes[0] = last; + } + // A dot on the start point is reached again at the end. + if out.dots.len() > first_dot + 1 && out.dots[first_dot].at.distance(out.dots[out.dots.len() - 1].at) < 1e-6 { + out.dots.pop(); + } + } + for d in &dashes { + write(&mut out.path, d); + } +} + +fn write(out: &mut BezPath, segs: &[PathSeg]) { + let Some(first) = segs.first() else { return }; + out.move_to(first.start()); + for s in segs { + push_seg(out, s); + } +} + +/// Curve parameter at arc length `s` along `seg` (of total length `len`). +fn param(seg: &PathSeg, len: f64, s: f64) -> f64 { + if s <= 0.0 { + 0.0 + } else if s >= len { + 1.0 + } else if let PathSeg::Line(_) = seg { + s / len + } else { + seg.inv_arclen(s, ARCLEN_ACCURACY) + } +} + +/// The part of `seg` between arc lengths `s0` and `s1`. +fn sub(seg: &PathSeg, len: f64, s0: f64, s1: f64) -> PathSeg { + seg.subsegment(param(seg, len, s0)..param(seg, len, s1)) +} + +/// Outlines of `dots` for a stroke of `width` with `cap`: discs (round), squares turned along the +/// path (projecting) or nothing (butt). Each outline winds like kurbo's stroke outlines, so a dot +/// touching a dash doesn't cancel it under the non-zero rule. +pub fn dot_outline(dots: &[Dot], width: f64, cap: LineCap, tol: f64) -> BezPath { + let mut out = BezPath::new(); + let r = width / 2.0; + if r <= 0.0 { + return out; + } + for d in dots { + match cap { + LineCap::Butt => {} + LineCap::Round => out.extend(kurbo::Circle::new(d.at, r).path_elements(tol)), + LineCap::Square => { + let (u, n) = (d.dir * r, Vec2::new(-d.dir.y, d.dir.x) * r); + out.move_to(d.at - u - n); + out.line_to(d.at + u - n); + out.line_to(d.at + u + n); + out.line_to(d.at - u + n); + out.close_path(); + } + } + } + out +} diff --git a/crates/effects/src/stroke/tests.rs b/crates/effects/src/stroke/tests.rs new file mode 100644 index 00000000..6811e810 --- /dev/null +++ b/crates/effects/src/stroke/tests.rs @@ -0,0 +1,305 @@ +use kurbo::{BezPath, PathEl, Point, Rect, Shape, Vec2}; +use vectorcraft_color::{Color, Paint}; +use vectorcraft_doc::{ArrowAlign, Arrowhead, Dash, LineCap, StrokeLayer, WidthProfile}; + +use super::*; + +fn line(x0: f64, x1: f64) -> BezPath { + let mut b = BezPath::new(); + b.move_to((x0, 0.0)); + b.line_to((x1, 0.0)); + b +} + +fn square(size: f64) -> BezPath { + Rect::new(0.0, 0.0, size, size).to_path(0.1) +} + +fn stroke(width: f64, f: impl FnOnce(&mut StrokeLayer)) -> StrokeLayer { + let mut st = StrokeLayer::new(Paint::solid(Color::BLACK), width); + f(&mut st); + st +} + +fn dashed(pattern: &[f64], offset: f64) -> Dash { + Dash { pattern: pattern.to_vec(), offset, align_corners: false } +} + +fn length(bp: &BezPath) -> f64 { + bp.segments().map(|s| kurbo::ParamCurveArclen::arclen(&s, 1e-9)).sum() +} + +fn moves(bp: &BezPath) -> usize { + bp.elements().iter().filter(|e| matches!(e, PathEl::MoveTo(_))).count() +} + +fn near(a: f64, b: f64, tol: f64) -> bool { + (a - b).abs() <= tol +} + +// ---------------------------------------------------------------- dashes and dots + +#[test] +fn zero_length_dashes_are_dots_along_the_tangent() { + let d = dash(&line(0.0, 60.0), &dashed(&[0.0, 6.0], 0.0)).unwrap(); + assert!(d.path.elements().is_empty(), "no dash has length"); + let xs: Vec = d.dots.iter().map(|p| p.at.x).collect(); + assert_eq!(d.dots.len(), 11, "{xs:?}"); + for (i, dot) in d.dots.iter().enumerate() { + assert!(near(dot.at.x, 6.0 * i as f64, 1e-9) && near(dot.at.y, 0.0, 1e-12)); + assert!(near(dot.dir.x, 1.0, 1e-12)); + } + // The offset shifts the dots along the path. + let d = dash(&line(0.0, 60.0), &dashed(&[0.0, 6.0], 3.0)).unwrap(); + assert_eq!(d.dots.len(), 10); + assert!(near(d.dots[0].at.x, 3.0, 1e-9)); + // Dots on a curve follow its direction. + let c = kurbo::Circle::new((0.0, 0.0), 50.0).to_path(1e-6); + let d = dash(&c, &dashed(&[0.0, 10.0], 0.0)).unwrap(); + for dot in &d.dots { + assert!(dot.dir.dot(dot.at.to_vec2()).abs() < 1e-3, "tangent ⟂ radius at {:?}", dot.at); + } +} + +#[test] +fn dots_on_a_closed_path_are_not_doubled_at_the_start() { + let d = dash(&square(60.0), &dashed(&[0.0, 6.0], 0.0)).unwrap(); + assert_eq!(d.dots.len(), 40); +} + +#[test] +fn dashes_follow_arc_length_and_join_across_the_start_of_closed_paths() { + let d = dash(&line(10.0, 90.0), &dashed(&[10.0, 10.0], 0.0)).unwrap(); + assert_eq!(moves(&d.path), 4); + assert!(near(length(&d.path), 40.0, 1e-6)); + // An odd pattern repeats with dashes and gaps swapped: 10 on, 10 off, 10 on… + let odd = dash(&line(0.0, 80.0), &dashed(&[10.0], 0.0)).unwrap(); + assert_eq!(moves(&odd.path), 4); + // Perimeter 400, dashes of 20 starting 10 into the pattern: the dash at 390..410 runs + // through the start point and is one dash. + let sq = dash(&square(100.0), &dashed(&[20.0, 20.0], 10.0)).unwrap(); + assert_eq!(moves(&sq.path), 10); + assert!(near(length(&sq.path), 200.0, 1e-6)); + // A pattern without length is a solid line; one dash round a closed path stays closed. + assert!(dash(&line(0.0, 10.0), &dashed(&[0.0, 0.0], 0.0)).is_none()); + let whole = dash(&square(10.0), &dashed(&[100.0, 1.0], 0.0)).unwrap(); + assert!(is_closed(&whole.path)); + // A pattern far too fine for the path is drawn solid rather than as millions of dashes. + assert!(dash(&line(0.0, 1e6), &dashed(&[0.001, 0.001], 0.0)).is_none()); +} + +#[test] +fn dot_outlines_take_the_cap_shape_and_wind_like_stroked_dashes() { + let dots = [Dot { at: Point::new(10.0, 0.0), dir: Vec2::new(1.0, 0.0) }]; + let round = dot_outline(&dots, 4.0, LineCap::Round, 1e-4); + assert!(near(round.area(), std::f64::consts::PI * 4.0, 1e-3)); + let sq = dot_outline(&dots, 4.0, LineCap::Square, 1e-4); + assert!(near(sq.area(), 16.0, 1e-9)); + assert!(sq.contains(Point::new(11.9, 1.9)) && !round.contains(Point::new(11.9, 1.9))); + assert!(dot_outline(&dots, 4.0, LineCap::Butt, 1e-4).elements().is_empty()); + // A dot overlapping a dash adds to it under the non-zero rule instead of cancelling it. + let dash_outline = kurbo::stroke(line(0.0, 10.0).iter(), &kurbo::Stroke::new(4.0), &Default::default(), 1e-4); + for o in [&round, &sq] { + assert_eq!(o.area().signum(), dash_outline.area().signum()); + } + let st = stroke(4.0, |s| { + s.cap = LineCap::Round; + s.dash = Some(dashed(&[10.0, 1.0, 0.0, 1.0], 0.0)); + }); + let o = line_outline(&line(0.0, 12.0), &st, 4.0, 1e-3); + assert!(o.contains(Point::new(10.5, 0.0)), "the dot overlapping the dash end is painted"); +} + +#[test] +fn line_outline_uses_the_profile_dashes_or_a_plain_stroke() { + let l = line(0.0, 100.0); + let plain = line_outline(&l, &stroke(10.0, |_| {}), 10.0, 1e-3); + assert!(near(plain.area().abs(), 1000.0, 1e-6)); + let lens = line_outline(&l, &stroke(10.0, |s| s.profile = Some(WidthProfile::lens())), 10.0, 1e-3); + assert!(near(lens.area().abs(), 500.0, 1e-6)); + // Dashes take precedence over a profile (as before). + let st = stroke(10.0, |s| { + s.profile = Some(WidthProfile::lens()); + s.dash = Some(dashed(&[25.0, 25.0], 0.0)); + }); + assert!(near(line_outline(&l, &st, 10.0, 1e-3).area().abs(), 500.0, 1e-6)); + assert!(line_outline(&BezPath::new(), &st, 10.0, 1e-3).elements().is_empty()); +} + +#[test] +fn aligned_width_doubles_only_closed_inside_and_outside_strokes() { + let mut st = stroke(3.0, |s| s.align = vectorcraft_doc::StrokeAlign::Inside); + assert_eq!(aligned_width(&st, true), 6.0); + assert_eq!(aligned_width(&st, false), 3.0); + st.align = vectorcraft_doc::StrokeAlign::Center; + assert_eq!(aligned_width(&st, true), 3.0); +} + +// ---------------------------------------------------------------- arrowheads + +fn arrows(kind: Arrowhead, align: ArrowAlign, cap: LineCap) -> StrokeLayer { + stroke(2.0, |s| { + s.end_arrow = Some(kind); + s.arrow_align = align; + s.cap = cap; + }) +} + +#[test] +fn no_heads_borrows_the_path_and_closed_paths_get_none() { + let l = line(0.0, 50.0); + assert!(matches!(stroke_pieces(&l, &stroke(2.0, |_| {})).line, Cow::Borrowed(_))); + let st = stroke(2.0, |s| { + s.start_arrow = Some(Arrowhead::Triangle); + s.end_arrow = Some(Arrowhead::Triangle); + s.arrow_align = ArrowAlign::Tip; + }); + let sq = square(50.0); + let p = stroke_pieces(&sq, &st); + assert!(p.heads.is_empty()); + assert_eq!(p.line.as_ref(), &sq); +} + +#[test] +fn tip_mode_shortens_the_stroke_by_the_head_and_puts_the_tip_on_the_end_point() { + for kind in Arrowhead::ALL { + let st = arrows(kind, ArrowAlign::Tip, LineCap::Butt); + let l = line(0.0, 100.0); + let p = stroke_pieces(&l, &st); + let [h] = &p.heads[..] else { panic!("one head") }; + assert_eq!(h.tip, Point::new(100.0, 0.0), "{kind:?}"); + assert!(near(h.dir.x, 1.0, 1e-9), "{kind:?}"); + assert!(h.inset > 0.0 && h.inset <= 8.0, "{kind:?} inset {}", h.inset); + assert!(near(length(&p.line), 100.0 - h.inset, 1e-6), "{kind:?}"); + // Nothing reaches past the tip. + assert!(h.outline.bounding_box().x1 <= 100.0 + 0.01, "{kind:?}"); + assert!(h.outline.area().abs() > 0.5, "{kind:?}"); + } + // Both ends, on a curve: the start head points back along the path. + let mut c = BezPath::new(); + c.move_to((0.0, 0.0)); + c.curve_to((30.0, -40.0), (70.0, -40.0), (100.0, 0.0)); + let st = stroke(2.0, |s| { + s.start_arrow = Some(Arrowhead::Triangle); + s.end_arrow = Some(Arrowhead::Arrow); + s.arrow_align = ArrowAlign::Tip; + }); + let p = stroke_pieces(&c, &st); + assert_eq!(p.heads.len(), 2); + assert_eq!(p.heads[0].tip, Point::new(0.0, 0.0)); + assert!(p.heads[0].dir.x < 0.0 && p.heads[0].dir.y > 0.0, "{:?}", p.heads[0].dir); + let total = length(&c); + assert!(near(length(&p.line), total - p.heads[0].inset - p.heads[1].inset, 1e-5)); + // A path shorter than its heads leaves no line. + let short = line(0.0, 3.0); + let p = stroke_pieces(&short, &arrows(Arrowhead::Triangle, ArrowAlign::Tip, LineCap::Butt)); + assert!(p.line.elements().is_empty()); + assert_eq!(p.heads.len(), 1); +} + +#[test] +fn extend_mode_keeps_the_path_and_overhangs_by_the_inset() { + let l = line(0.0, 100.0); + let st = arrows(Arrowhead::Triangle, ArrowAlign::Extend, LineCap::Butt); + let p = stroke_pieces(&l, &st); + assert!(matches!(p.line, Cow::Borrowed(_))); + let h = &p.heads[0]; + assert!(near(h.tip.x, 100.0 + h.inset, 1e-9)); + // The same head as in tip mode, moved by the overhang. + let tip = stroke_pieces(&l, &arrows(Arrowhead::Triangle, ArrowAlign::Tip, LineCap::Butt)); + let mut moved = tip.heads[0].outline.clone(); + moved.apply_affine(kurbo::Affine::translate((h.inset, 0.0))); + let pts = |b: &BezPath| b.elements().iter().filter_map(|e| e.end_point()).collect::>(); + let (a, b) = (pts(&moved), pts(&h.outline)); + assert_eq!(a.len(), b.len()); + assert!(a.iter().zip(&b).all(|(p, q)| p.distance(*q) < 1e-9)); +} + +#[test] +fn hollow_heads_are_rings_and_the_stroke_stays_out_of_the_hole() { + for (kind, cap) in [(Arrowhead::CircleOpen, LineCap::Round), (Arrowhead::SquareOpen, LineCap::Square), (Arrowhead::TriangleOpen, LineCap::Butt)] { + let st = arrows(kind, ArrowAlign::Tip, cap); + let l = line(0.0, 100.0); + let p = stroke_pieces(&l, &st); + let h = &p.heads[0]; + let line_o = line_outline(&p.line, &st, st.width, 1e-3); + // A point inside the hole is neither head nor line. + let hole = Point::new(100.0 - 8.0 * 0.45, 0.0); + assert_eq!(h.outline.winding(hole), 0, "{kind:?} hole"); + assert_eq!(line_o.winding(hole), 0, "{kind:?} line in the hole"); + // The line reaches the back wall, so they overlap (no seam). + let back_wall = Point::new(100.0 - 8.0 + 0.25, 0.0); + assert_ne!(h.outline.winding(back_wall), 0, "{kind:?} wall"); + assert_ne!(line_o.winding(back_wall - Vec2::new(0.2, 0.0)), 0, "{kind:?} line reaches the wall"); + } + // The open arrow is a chevron: open between its arms. + let l = line(0.0, 100.0); + let p = stroke_pieces(&l, &arrows(Arrowhead::ArrowOpen, ArrowAlign::Tip, LineCap::Butt)); + let h = &p.heads[0]; + assert_eq!(h.outline.winding(Point::new(93.0, 0.0)), 0); + assert_ne!(h.outline.winding(Point::new(99.0, 0.0)), 0); +} + +#[test] +fn round_caps_never_poke_past_the_tip() { + for kind in Arrowhead::ALL { + for scale in [10.0, 100.0, 300.0] { + let mut st = arrows(kind, ArrowAlign::Tip, LineCap::Round); + st.arrow_scale = (scale, scale); + let l = line(0.0, 100.0); + let p = stroke_pieces(&l, &st); + let o = line_outline(&p.line, &st, st.width, 1e-3); + assert!(o.bounding_box().x1 <= 100.0 + 1e-3, "{kind:?} at {scale}%: {}", o.bounding_box().x1); + } + } +} + +// ---------------------------------------------------------------- robustness + +#[test] +fn degenerate_paths_and_patterns_neither_panic_nor_hang() { + let finite = |b: &BezPath| b.elements().iter().filter_map(|e| e.end_point()).all(|q| q.x.is_finite() && q.y.is_finite()); + let mut point = BezPath::new(); + point.move_to((0.0, 0.0)); + let lone = point.clone(); + point.line_to((0.0, 0.0)); + let mut still_curve = BezPath::new(); + still_curve.move_to((0.0, 0.0)); + still_curve.curve_to((0.0, 0.0), (0.0, 0.0), (0.0, 0.0)); + // Drawing on after a ClosePath, and curves whose handles sit on their end points. + let mut mixed = BezPath::new(); + mixed.move_to((0.0, 0.0)); + mixed.line_to((10.0, 0.0)); + mixed.close_path(); + mixed.line_to((5.0, 5.0)); + mixed.move_to((20.0, 0.0)); + mixed.curve_to((20.0, 0.0), (50.0, 50.0), (50.0, 50.0)); + mixed.quad_to((50.0, 50.0), (90.0, 0.0)); + let paths = [BezPath::new(), lone, point, still_curve, mixed, square(20.0)]; + // Negative, non-finite and sub-tolerance entries (the last used to loop forever on a + // zero-length path), and offsets far outside the pattern. + let patterns: [&[f64]; 6] = [&[0.0, 6.0], &[-1.0, 3.0], &[f64::NAN, 1.0], &[1e-12, 1e-12], &[0.0], &[3.0, 0.0]]; + for bp in &paths { + for kind in Arrowhead::ALL { + for align in [ArrowAlign::Extend, ArrowAlign::Tip] { + for cap in [LineCap::Butt, LineCap::Round, LineCap::Square] { + for pat in patterns { + for off in [0.0, -7.0, 1e12, f64::INFINITY] { + let st = stroke(2.0, |s| { + s.start_arrow = Some(kind); + s.end_arrow = Some(kind); + s.arrow_align = align; + s.cap = cap; + s.dash = Some(dashed(pat, off)); + }); + let p = stroke_pieces(bp, &st); + assert!(p.heads.iter().all(|h| finite(&h.outline)), "{bp:?} {kind:?}"); + assert!(finite(&line_outline(&p.line, &st, 2.0, 0.01)), "{bp:?} {pat:?} {off}"); + } + } + } + } + } + } + assert!(dash(&line(0.0, 1e-9), &dashed(&[1e-12, 1e-12], 0.0)).is_none(), "too fine to advance: solid"); +} diff --git a/crates/render/src/width.rs b/crates/effects/src/stroke/width.rs similarity index 89% rename from crates/render/src/width.rs rename to crates/effects/src/stroke/width.rs index 5ec8d5e7..aef94bf6 100644 --- a/crates/render/src/width.rs +++ b/crates/effects/src/stroke/width.rs @@ -6,24 +6,10 @@ //! projecting caps (the round cap blends the two side widths); closed subpaths become two loops //! of opposite orientation filled with the non-zero rule. -use vectorcraft_doc::{LineCap, StrokeAlign, StrokeLayer, WidthProfile}; -use vectorcraft_geom::kurbo::{self, BezPath, PathEl, Point, Vec2}; +use kurbo::{BezPath, PathEl, Point, Vec2}; +use vectorcraft_doc::{LineCap, WidthProfile}; -/// The outline to fill instead of stroking, when `st` has a width profile (and no dashes). -pub(crate) fn outline_for(bp: &BezPath, st: &StrokeLayer, tol: f64) -> Option { - let profile = st.profile.as_ref()?; - if st.dash.as_ref().is_some_and(|d| d.is_dashed()) { - return None; - } - let closed = bp.elements().last().is_some_and(|e| matches!(e, PathEl::ClosePath)); - let width = match st.align { - StrokeAlign::Center => st.width, - _ if closed => st.width * 2.0, - _ => st.width, - }; - let o = width_outline(bp, width, profile, st.cap, tol); - (!o.elements().is_empty()).then_some(o) -} +use super::unit; /// Filled outline of `bp` stroked with `width` scaled by `profile`, flattened to `tol`. pub fn width_outline(bp: &BezPath, width: f64, profile: &WidthProfile, cap: LineCap, tol: f64) -> BezPath { @@ -72,11 +58,6 @@ fn subpaths(bp: &BezPath, tol: f64) -> Vec<(Vec, bool)> { out } -fn unit(v: Vec2) -> Vec2 { - let h = v.hypot(); - if h > 1e-12 { v / h } else { Vec2::new(1.0, 0.0) } -} - /// Left normal in y-down space (left of the direction of travel). fn left(t: Vec2) -> Vec2 { Vec2::new(t.y, -t.x) @@ -255,7 +236,5 @@ mod tests { let a = area(&width_outline(&c, 10.0, &p, LineCap::Butt, 0.001)); let want = 2.0 * std::f64::consts::PI * 50.0 * 10.0; assert!((a - want).abs() / want < 0.01, "{a} vs {want}"); - let st = StrokeLayer { profile: None, ..StrokeLayer::new(vectorcraft_color::Paint::solid(vectorcraft_color::Color::BLACK), 4.0) }; - assert!(outline_for(&c, &st, 0.1).is_none()); } } diff --git a/crates/engine/src/cmd/stroke.rs b/crates/engine/src/cmd/stroke.rs index c97ace47..2f89ef7c 100644 --- a/crates/engine/src/cmd/stroke.rs +++ b/crates/engine/src/cmd/stroke.rs @@ -2,7 +2,7 @@ use serde_json::Value; use vectorcraft_color::{Color, Paint}; -use vectorcraft_doc::{Arrowhead, Dash, LineCap, LineJoin, StrokeAlign, StrokeLayer}; +use vectorcraft_doc::{ArrowAlign, Arrowhead, Dash, LineCap, LineJoin, StrokeAlign, StrokeLayer, WidthProfile}; use super::*; @@ -13,7 +13,7 @@ pub fn specs() -> Vec { "Stroke Options", ["Window", "Stroke"], None, - "{weight?, cap?: butt|round|square, join?: miter|round|bevel, miterLimit?, align?: center|inside|outside, dash?: [d,g,…]|null, dashOffset?, alignDashes?, startArrow?, endArrow?: name|null, profile?: \"uniform\"|\"lens\"|\"taperStart\"|\"taperEnd\", ids?}", + "{weight?, cap?: butt|round|square, join?: miter|round|bevel, miterLimit?, align?: center|inside|outside, dash?: [d,g,…]|null (a 0 dash with a round or projecting cap draws dots or squares), dashOffset?, alignDashes?, startArrow?, endArrow?: Arrow|ArrowOpen|Triangle|TriangleOpen|Circle|CircleOpen|Square|SquareOpen|Diamond|Bar|null, arrowAlign?: \"extend\" (tip past the end point, default)|\"tip\" (tip on the end point; the stroke is shortened), profile?: \"uniform\"|\"lens\"|\"taperStart\"|\"taperEnd\", ids?}", has_doc, stroke_set ), @@ -48,6 +48,17 @@ fn stroke_set(s: &mut Session, p: &Value) -> Result { } }; let (sa, ea) = (arrow("startArrow")?, arrow("endArrow")?); + let arrow_align = match str_param(p, "arrowAlign") { + None => None, + Some("extend") => Some(ArrowAlign::Extend), + Some("tip") => Some(ArrowAlign::Tip), + Some(o) => return Err(bad("stroke.set", format!("arrowAlign must be extend|tip, got {o}"))), + }; + let profile = match str_param(p, "profile") { + None => None, + Some("uniform") => Some(None), + Some(id) => Some(Some(WidthProfile::preset(id).ok_or_else(|| bad("stroke.set", format!("unknown profile {id}")))?)), + }; s.edit("Stroke", |d, _| { for id in &ids { let Some(n) = d.node_mut(*id) else { continue }; @@ -97,12 +108,11 @@ fn stroke_set(s: &mut Session, p: &Value) -> Result { if let Some(a) = ea { st.end_arrow = a; } - match str_param(p, "profile") { - Some("uniform") => st.profile = None, - Some("lens") => st.profile = Some(vectorcraft_doc::WidthProfile::lens()), - Some("taperStart") => st.profile = Some(vectorcraft_doc::WidthProfile::taper_start()), - Some("taperEnd") => st.profile = Some(vectorcraft_doc::WidthProfile::taper_end()), - _ => {} + if let Some(a) = arrow_align { + st.arrow_align = a; + } + if let Some(pr) = &profile { + st.profile = pr.clone(); } } Ok(()) @@ -111,11 +121,11 @@ fn stroke_set(s: &mut Session, p: &Value) -> Result { } /// Mirror a width profile along the path (t → 1 − t) or across it (swap left/right widths). -pub(crate) fn flip_profile(p: &vectorcraft_doc::WidthProfile, along: bool) -> vectorcraft_doc::WidthProfile { +pub(crate) fn flip_profile(p: &WidthProfile, along: bool) -> WidthProfile { let mut pts: Vec<(f64, f64, f64)> = if along { p.points.iter().map(|&(t, l, r)| (1.0 - t, l, r)).collect() } else { p.points.iter().map(|&(t, l, r)| (t, r, l)).collect() }; pts.sort_by(|a, b| a.0.total_cmp(&b.0)); - vectorcraft_doc::WidthProfile { points: pts } + WidthProfile { points: pts } } fn stroke_advanced(s: &mut Session, p: &Value) -> Result { diff --git a/crates/engine/src/lib.rs b/crates/engine/src/lib.rs index 53850b00..7b325cf6 100644 --- a/crates/engine/src/lib.rs +++ b/crates/engine/src/lib.rs @@ -742,6 +742,8 @@ mod tests_prefs; #[cfg(test)] mod tests_swatches; #[cfg(test)] +mod tests_strokegeom; +#[cfg(test)] mod tests_textedit; #[cfg(test)] mod tests_xform; diff --git a/crates/engine/src/tests_strokegeom.rs b/crates/engine/src/tests_strokegeom.rs new file mode 100644 index 00000000..ee43644c --- /dev/null +++ b/crates/engine/src/tests_strokegeom.rs @@ -0,0 +1,76 @@ +//! Stroke geometry from the Stroke panel's commands (`cmd/stroke.rs`): arrowhead alignment and +//! the width-profile presets. + +use serde_json::json; +use vectorcraft_doc::{ArrowAlign, StrokeLayer, WidthProfile}; + +use super::*; + +fn session_with_line() -> (Session, NodeId) { + let mut s = Session::new(); + s.execute("file.new", &json!({"width": 200, "height": 200})).unwrap(); + let r = s.execute("shape.line", &json!({"x1": 10, "y1": 100, "x2": 150, "y2": 100})).unwrap(); + (s, NodeId(r["id"].as_u64().unwrap())) +} + +fn stroke(s: &Session, id: NodeId) -> StrokeLayer { + s.doc().unwrap().doc.node(id).unwrap().appearance.stroke().unwrap().clone() +} + +#[test] +fn arrow_align_is_set_per_stroke_and_validated() { + let (mut s, id) = session_with_line(); + assert_eq!(stroke(&s, id).arrow_align, ArrowAlign::Extend); + s.execute("stroke.set", &json!({"endArrow": "TriangleOpen", "arrowAlign": "tip"})).unwrap(); + let st = stroke(&s, id); + assert_eq!((st.end_arrow, st.arrow_align), (Some(vectorcraft_doc::Arrowhead::TriangleOpen), ArrowAlign::Tip)); + s.execute("stroke.set", &json!({"arrowAlign": "extend", "ids": [id.0]})).unwrap(); + assert_eq!(stroke(&s, id).arrow_align, ArrowAlign::Extend); + assert!(s.execute("stroke.set", &json!({"arrowAlign": "middle"})).is_err()); + s.execute("edit.undo", &json!({})).unwrap(); + assert_eq!(stroke(&s, id).arrow_align, ArrowAlign::Tip); +} + +#[test] +fn profiles_come_from_the_preset_catalogue() { + let (mut s, id) = session_with_line(); + for p in WidthProfile::PRESETS { + s.execute("stroke.set", &json!({"profile": p.id})).unwrap(); + let st = stroke(&s, id); + assert_eq!(WidthProfile::id_of(st.profile.as_ref()), p.id); + } + assert!(stroke(&s, id).profile.is_some()); + s.execute("stroke.set", &json!({"profile": "uniform"})).unwrap(); + assert!(stroke(&s, id).profile.is_none(), "uniform is the plain stroke"); + assert!(s.execute("stroke.set", &json!({"profile": "zigzag"})).is_err()); + // The params doc (what agents read) lists every preset and the arrow alignment. + let spec = command_specs().iter().find(|c| c.id == "stroke.set").unwrap(); + for p in WidthProfile::PRESETS { + assert!(spec.params.contains(&format!("\"{}\"", p.id)), "{}", p.id); + } + assert!(spec.params.contains("arrowAlign")); + // …and every arrowhead name `startArrow`/`endArrow` accept. + for a in vectorcraft_doc::Arrowhead::ALL { + let name = serde_json::to_value(a).unwrap(); + assert!(spec.params.contains(name.as_str().unwrap()), "{name}"); + s.execute("stroke.set", &json!({"endArrow": name})).unwrap(); + assert_eq!(stroke(&s, id).end_arrow, Some(a)); + } +} + +#[test] +fn arrow_align_and_profiles_survive_the_native_format() { + let (mut s, id) = session_with_line(); + s.execute( + "stroke.set", + &json!({"startArrow": "CircleOpen", "endArrow": "Arrow", "arrowAlign": "tip", "profile": "lens", "dash": [0, 6], "cap": "round"}), + ) + .unwrap(); + let doc = &s.doc().unwrap().doc; + let back = vectorcraft_format::load(&vectorcraft_format::save(doc, false)).unwrap(); + assert_eq!(back.node(id).unwrap().appearance.stroke().unwrap(), &stroke(&s, id)); + // A stroke with the default alignment writes nothing new, so older builds read it unchanged. + s.execute("stroke.set", &json!({"arrowAlign": "extend"})).unwrap(); + let text = String::from_utf8(vectorcraft_format::save(&s.doc().unwrap().doc, true)).unwrap(); + assert!(!text.contains("arrow_align")); +} diff --git a/crates/pdf/src/export.rs b/crates/pdf/src/export.rs index cc7179a1..935f442c 100644 --- a/crates/pdf/src/export.rs +++ b/crates/pdf/src/export.rs @@ -11,10 +11,10 @@ use krilla::num::NormalizedF32; use krilla::page::PageSettings; use krilla::paint::{Fill, LinearGradient, RadialGradient, SpreadMethod, Stop, Stroke, StrokeDash}; use krilla::surface::Surface; -use kurbo::{ParamCurve, ParamCurveDeriv, PathEl, Shape, Vec2}; +use kurbo::{PathEl, Shape, Vec2}; use vectorcraft_color::{BlendMode, Color, GradientKind, Paint}; use vectorcraft_doc::appearance::stroke_paint_bounds; -use vectorcraft_doc::{AppearanceItem, Arrowhead, Document, LineCap, LineJoin, Node, NodeKind, StrokeAlign, StrokeLayer, TextObject}; +use vectorcraft_doc::{AppearanceItem, Document, LineCap, LineJoin, Node, NodeKind, StrokeAlign, StrokeLayer, TextObject}; use vectorcraft_geom::{Affine, BezPath, FillRule, Rect}; use crate::{Compatibility, ExportReport, PdfError, PdfOptions}; @@ -522,6 +522,18 @@ impl Exporter<'_> { s.push_blend_mode(blend(st.blend)); pushes += 1; } + // The line ends under its arrowheads; they overlap, so both take the opacity once, as a group. + let pieces = vectorcraft_effects::stroke::stroke_pieces(bp, st); + let grouped = !pieces.heads.is_empty() && st.opacity < 1.0; + if grouped { + s.push_opacity(norm(st.opacity)); + pushes += 1; + } + let opacity = if grouped { NormalizedF32::ONE } else { norm(st.opacity) }; + let trimmed = match &pieces.line { + std::borrow::Cow::Owned(line) => Some(to_path(line)), + std::borrow::Cow::Borrowed(_) => None, + }; let width = match st.align { StrokeAlign::Center => st.width, _ if closed => st.width * 2.0, @@ -566,20 +578,23 @@ impl Exporter<'_> { LineJoin::Round => krilla::paint::LineJoin::Round, LineJoin::Bevel => krilla::paint::LineJoin::Bevel, }, - opacity: norm(st.opacity), + opacity, dash, })); - s.draw_path(path); + // A line fully covered by its heads (Tip alignment) has nothing left to stroke. + if let Some(line) = trimmed.as_ref().map_or(Some(path), Option::as_ref) { + s.draw_path(line); + } s.set_stroke(None); // Pop the alignment clip before drawing arrowheads. if matches!(st.align, StrokeAlign::Inside | StrokeAlign::Outside) && closed && pushes > 0 { s.pop(); pushes -= 1; } - if st.start_arrow.is_some() || st.end_arrow.is_some() { - for head in arrowheads(bp, st) { - if let Some(p) = to_path(&head) { - s.set_fill(Some(Fill { paint: paint.clone(), opacity: norm(st.opacity), rule: krilla::paint::FillRule::NonZero })); + if !pieces.heads.is_empty() { + s.set_fill(Some(Fill { paint, opacity, rule: krilla::paint::FillRule::NonZero })); + for head in &pieces.heads { + if let Some(p) = to_path(&head.outline) { s.draw_path(&p); } } @@ -678,78 +693,3 @@ impl Exporter<'_> { s.pop(); } } - -/// Arrowhead outlines for a stroke (same geometry as the renderer). -fn arrowheads(bp: &BezPath, st: &StrokeLayer) -> Vec { - let segs: Vec = bp.segments().collect(); - let mut out = Vec::new(); - let (Some(first), Some(last)) = (segs.first(), segs.last()) else { return out }; - if let Some(a) = st.start_arrow { - out.push(head(a, first.eval(0.0), tangent(first, 0.0) * -1.0, st.width * st.arrow_scale.0 / 100.0)); - } - if let Some(a) = st.end_arrow { - out.push(head(a, last.eval(1.0), tangent(last, 1.0), st.width * st.arrow_scale.1 / 100.0)); - } - out -} - -fn tangent(s: &kurbo::PathSeg, t: f64) -> Vec2 { - let d = match s { - kurbo::PathSeg::Line(l) => l.p1 - l.p0, - kurbo::PathSeg::Quad(q) => q.deriv().eval(t).to_vec2(), - kurbo::PathSeg::Cubic(c) => { - let v = c.deriv().eval(t).to_vec2(); - if v.hypot() < 1e-9 { c.p3 - c.p0 } else { v } - } - }; - let l = d.hypot(); - if l < 1e-12 { Vec2::new(1.0, 0.0) } else { d / l } -} - -fn head(kind: Arrowhead, tip: kurbo::Point, dir: Vec2, w: f64) -> BezPath { - let w = w.max(0.25); - let n = Vec2::new(-dir.y, dir.x); - let len = 4.0 * w; - let half = 2.0 * w; - let base = tip - dir * len; - let mut p = BezPath::new(); - match kind { - Arrowhead::Triangle | Arrowhead::TriangleOpen | Arrowhead::Arrow | Arrowhead::ArrowOpen => { - p.move_to(tip); - p.line_to(base + n * half); - if matches!(kind, Arrowhead::Arrow | Arrowhead::ArrowOpen) { - p.line_to(tip - dir * (len * 0.7)); - } - p.line_to(base - n * half); - p.close_path(); - } - Arrowhead::Circle | Arrowhead::CircleOpen => { - p = kurbo::Circle::new(tip - dir * half, half).to_path(0.01); - } - Arrowhead::Square | Arrowhead::SquareOpen => { - let c = tip - dir * half; - p.move_to(c + dir * half + n * half); - p.line_to(c - dir * half + n * half); - p.line_to(c - dir * half - n * half); - p.line_to(c + dir * half - n * half); - p.close_path(); - } - Arrowhead::Diamond => { - let c = tip - dir * half; - p.move_to(tip); - p.line_to(c + n * half); - p.line_to(c - dir * half); - p.line_to(c - n * half); - p.close_path(); - } - Arrowhead::Bar => { - let t = w * 0.75; - p.move_to(tip + n * half); - p.line_to(tip + n * half - dir * t); - p.line_to(tip - n * half - dir * t); - p.line_to(tip - n * half); - p.close_path(); - } - } - p -} diff --git a/crates/pdf/src/lib.rs b/crates/pdf/src/lib.rs index ed602a51..680c0076 100644 --- a/crates/pdf/src/lib.rs +++ b/crates/pdf/src/lib.rs @@ -105,3 +105,5 @@ pub enum PdfError { #[cfg(test)] mod tests; +#[cfg(test)] +mod tests_stroke; diff --git a/crates/pdf/src/tests_stroke.rs b/crates/pdf/src/tests_stroke.rs new file mode 100644 index 00000000..26515ccf --- /dev/null +++ b/crates/pdf/src/tests_stroke.rs @@ -0,0 +1,92 @@ +//! Stroke geometry in PDF export: arrowheads and the trimmed line come from the shared +//! `vectorcraft_effects::stroke` geometry, and they take the stroke opacity once. + +use vectorcraft_color::{Color, Paint}; +use vectorcraft_doc::{Appearance, AppearanceItem, ArrowAlign, Arrowhead, Document, Node, NodeId, NodeKind, StrokeLayer}; +use vectorcraft_effects::stroke::stroke_pieces; +use vectorcraft_geom::{Point, Rect, Shape, shapes}; + +use crate::*; + +fn line_doc(st: StrokeLayer) -> (Document, Node) { + let mut d = Document::new(100.0, 100.0); + let mut n = Node::path( + NodeId(0), + shapes::line(Point::new(20.0, 50.0), Point::new(80.0, 50.0)), + Appearance { items: vec![AppearanceItem::Stroke(st)], effects: vec![] }, + ); + n.id = d.alloc_id(); + let layer = d.default_layer().unwrap(); + d.insert(Some(layer), 0, n.clone()).unwrap(); + (d, n) +} + +fn arrow_stroke(kind: Arrowhead, align: ArrowAlign, opacity: f32) -> StrokeLayer { + let mut st = StrokeLayer::new(Paint::solid(Color::BLACK), 4.0); + st.end_arrow = Some(kind); + st.arrow_align = align; + st.opacity = opacity; + st +} + +fn close(a: Rect, b: Rect) -> bool { + [(a.x0, b.x0), (a.y0, b.y0), (a.x1, b.x1), (a.y1, b.y1)].iter().all(|(p, q)| (p - q).abs() < 0.01) +} + +/// Bounding boxes of the filled and the stroked paths of a PDF read back. +fn painted_boxes(d: &Document) -> (Vec, Vec) { + let back = import(&export(d, &PdfOptions::default()).unwrap()).unwrap(); + let (mut fills, mut strokes) = (vec![], vec![]); + back.walk(|m| { + let Some(bb) = m.geometric_bounds().filter(|_| matches!(m.kind, NodeKind::Path { .. } | NodeKind::Compound { .. })) else { return }; + match m.appearance.items.first() { + Some(AppearanceItem::Fill(_)) => fills.push(bb), + Some(AppearanceItem::Stroke(_)) => strokes.push(bb), + None => {} + } + }); + (fills, strokes) +} + +#[test] +fn arrowheads_and_the_trimmed_line_match_the_shared_geometry() { + for align in [ArrowAlign::Extend, ArrowAlign::Tip] { + for kind in Arrowhead::ALL { + let (d, n) = line_doc(arrow_stroke(kind, align, 1.0)); + let bp = n.path_data().unwrap().to_bezpath(); + let pieces = stroke_pieces(&bp, n.appearance.stroke().unwrap()); + let (fills, strokes) = painted_boxes(&d); + let head = pieces.heads[0].outline.bounding_box(); + assert_eq!(fills.len(), 1, "{kind:?} {align:?}: one head"); + assert!(close(fills[0], head), "{kind:?} {align:?}: {:?} vs {head:?}", fills[0]); + assert_eq!(strokes.len(), 1, "{kind:?} {align:?}: one line"); + assert!(close(strokes[0], pieces.line.bounding_box()), "{kind:?} {align:?}: {:?}", strokes[0]); + if align == ArrowAlign::Tip { + assert!((strokes[0].x1 - (80.0 - pieces.heads[0].inset)).abs() < 0.01, "{kind:?}: the stroke stops under the head"); + } + } + } +} + +#[test] +fn line_and_head_share_one_opacity_group() { + let (d, _) = line_doc(arrow_stroke(Arrowhead::Triangle, ArrowAlign::Tip, 0.5)); + let back = import(&export(&d, &PdfOptions::default()).unwrap()).unwrap(); + let mut group_opacity = None; + let mut leaf_opacities = vec![]; + back.walk(|m| match &m.kind { + NodeKind::Group { .. } if m.opacity < 1.0 => group_opacity = Some(m.opacity), + NodeKind::Path { .. } => { + leaf_opacities.push(m.opacity); + for i in &m.appearance.items { + leaf_opacities.push(match i { + AppearanceItem::Fill(f) => f.opacity, + AppearanceItem::Stroke(s) => s.opacity, + }); + } + } + _ => {} + }); + assert!(group_opacity.is_some_and(|o| (o - 0.5).abs() < 0.01), "{group_opacity:?}"); + assert!(leaf_opacities.iter().all(|o| (o - 1.0).abs() < 1e-3), "{leaf_opacities:?}"); +} diff --git a/crates/render/src/lib.rs b/crates/render/src/lib.rs index f7d72e92..19579ef7 100644 --- a/crates/render/src/lib.rs +++ b/crates/render/src/lib.rs @@ -12,23 +12,22 @@ mod live; mod paint; mod pattern; pub mod proof; -mod width; use std::collections::HashMap; use std::sync::Arc; use vectorcraft_doc::appearance::stroke_paint_bounds; -use vectorcraft_doc::{AppearanceItem, Document, LineCap, LineJoin, Node, NodeId, NodeKind, StrokeAlign, StrokeLayer, TextObject}; +use vectorcraft_doc::{AppearanceItem, Document, Node, NodeId, NodeKind, StrokeAlign, StrokeLayer, TextObject}; use vectorcraft_geom::{Affine, BezPath, FillRule, Rect, Shape}; use vello_cpu::kurbo; use vello_cpu::peniko::{self, BlendMode, Compose, Mix}; use vello_cpu::{Pixmap, RenderContext, Resources}; +pub use effects::stroke::width_outline; pub use live::expand_live; pub use pattern::render_pattern_swatch; pub use vectorcraft_effects as effects; pub use vello_cpu; -pub use width::width_outline; /// Largest raster an export may ask [`Renderer::render_region`] for, per side. The CPU rasteriser /// addresses at most `u16::MAX` pixels per side (and panics at that edge). @@ -673,57 +672,36 @@ impl Renderer { } fn draw_stroke(&mut self, ctx: &mut RenderContext, f: &Frame, bp: &BezPath, rule: FillRule, st: &StrokeLayer, bounds: Rect) { - let layered = st.opacity < 1.0 || st.blend != vectorcraft_color::BlendMode::Normal || st.align == StrokeAlign::Outside; + let pieces = effects::stroke::stroke_pieces(bp, st); + // The line and its heads overlap: they take the opacity once, in one layer, instead of + // each folding it into its paint. + let folded = if pieces.heads.is_empty() { 1.0 } else { std::mem::replace(&mut self.alpha, 1.0) }; + let opacity = st.opacity * folded; + let layered = opacity < 1.0 || st.blend != vectorcraft_color::BlendMode::Normal || st.align == StrokeAlign::Outside; if layered { ctx.set_transform(Affine::IDENTITY); - ctx.push_layer(None, Some(blend_mode(st.blend)), Some(st.opacity), None, None); + ctx.push_layer(None, Some(blend_mode(st.blend)), Some(opacity), None, None); } ctx.set_transform(f.view); - let closed = bp.elements().last().is_some_and(|e| matches!(e, kurbo::PathEl::ClosePath)); - let width = match st.align { - StrokeAlign::Center => st.width, - _ if closed => st.width * 2.0, - _ => st.width, - }; - // Keep hairlines visible when zoomed far out (Illustrator shows at least ~1 device pixel). - let width = width.max(f.px * 0.5); - let mut stroke = kurbo::Stroke::new(width) - .with_join(match st.join { - LineJoin::Miter => kurbo::Join::Miter, - LineJoin::Round => kurbo::Join::Round, - LineJoin::Bevel => kurbo::Join::Bevel, - }) - .with_caps(match st.cap { - LineCap::Butt => kurbo::Cap::Butt, - LineCap::Round => kurbo::Cap::Round, - LineCap::Square => kurbo::Cap::Square, - }) - .with_miter_limit(st.miter_limit); - if let Some(d) = &st.dash - && d.is_dashed() - { - let mut pat = d.pattern.clone(); - if pat.len() % 2 == 1 { - pat.extend(pat.clone()); - } - stroke = stroke.with_dashes(d.offset, pat); - } - ctx.set_stroke(stroke.clone()); + let closed = effects::stroke::is_closed(bp); + // Keep hairlines visible when zoomed far out (at least ~1 device pixel). + let width = effects::stroke::aligned_width(st, closed).max(f.px * 0.5); let inside = st.align == StrokeAlign::Inside && closed; if inside { ctx.set_fill_rule(fill_rule(rule)); ctx.push_clip_layer(bp); } - if paint::set_paint(ctx, &st.paint, bounds.inflate(st.width / 2.0, st.width / 2.0), f.doc) { + // One paint box for the line and the heads, so a gradient runs on into the heads. + let paint_bounds = bounds.inflate(st.width / 2.0, st.width / 2.0); + if paint::set_paint(ctx, &st.paint, paint_bounds, f.doc) { self.fold_alpha(ctx, &st.paint); - if let Some(o) = width::outline_for(bp, st, f.px * 0.25) { - ctx.set_fill_rule(peniko::Fill::NonZero); - ctx.fill_path(&o); - } else if let Some(o) = self.cached_stroke(f, bp, st, &stroke) { - ctx.set_fill_rule(peniko::Fill::NonZero); - ctx.fill_path(&o); - } else { - ctx.stroke_path(bp); + ctx.set_fill_rule(peniko::Fill::NonZero); + match self.cached_stroke(f, &pieces.line, st, width) { + Some(o) => ctx.fill_path(&o), + None => ctx.fill_path(&effects::stroke::line_outline(&pieces.line, st, width, f.px * 0.25)), + } + for head in &pieces.heads { + ctx.fill_path(&head.outline); } } if inside { @@ -737,36 +715,29 @@ impl Renderer { ctx.fill_path(bp); ctx.set_blend_mode(BlendMode::default()); } - // Arrowheads. - if st.start_arrow.is_some() || st.end_arrow.is_some() { - for (arrow, head) in paint::arrowheads(bp, st) { - let _ = arrow; - if paint::set_paint(ctx, &st.paint, bounds, f.doc) { - ctx.set_fill_rule(peniko::Fill::NonZero); - ctx.fill_path(&head); - } - } - } if layered { ctx.pop_layer(); } + if !pieces.heads.is_empty() { + self.alpha = folded; + } } - /// The stroke of the fast-path node `self.cur` expanded to a fill outline in document space, - /// cached across frames. The tolerance (vello's 0.25 device px) is bucketed to powers of two, - /// never coarser than needed, so zooming reuses outlines until the level changes. - fn cached_stroke(&mut self, f: &Frame, bp: &BezPath, st: &StrokeLayer, stroke: &kurbo::Stroke) -> Option> { + /// The line part of a stroke of the fast-path node `self.cur` (see + /// [`effects::stroke::line_outline`]), cached across frames. The tolerance (vello's 0.25 + /// device px) is bucketed to powers of two, never coarser than needed, so zooming reuses + /// outlines until the level changes. + fn cached_stroke(&mut self, f: &Frame, line: &BezPath, st: &StrokeLayer, width: f64) -> Option> { let node = self.cur.clone()?; let level = (f.px * 0.25).log2().floor() as i32; - let key = (st as *const StrokeLayer as usize, stroke.width.to_bits(), level); + let key = (st as *const StrokeLayer as usize, width.to_bits(), level); if let Some(e) = self.strokes.get_mut(&key) && Arc::ptr_eq(&e.node, &node) { e.stamp = self.stamp; return Some(e.outline.clone()); } - let tolerance = 2f64.powi(level); - let outline = Arc::new(kurbo::stroke(bp.iter(), stroke, &kurbo::StrokeOpts::default(), tolerance)); + let outline = Arc::new(effects::stroke::line_outline(line, st, width, 2f64.powi(level))); self.strokes.insert(key, StrokeEntry { node, outline: outline.clone(), stamp: self.stamp }); Some(outline) } diff --git a/crates/render/src/paint.rs b/crates/render/src/paint.rs index 8c3d030a..c33e89c5 100644 --- a/crates/render/src/paint.rs +++ b/crates/render/src/paint.rs @@ -1,10 +1,9 @@ -//! Paint conversion (solid, gradients, patterns), arrowheads and image decoding. +//! Paint conversion (solid, gradients, patterns) and image decoding. use vectorcraft_color::{GradientKind, Paint}; -use vectorcraft_doc::{Arrowhead, Document, StrokeLayer}; -use vectorcraft_geom::{Affine, BezPath, Point, Rect, Shape, Vec2}; +use vectorcraft_doc::Document; +use vectorcraft_geom::{Affine, Rect, Vec2}; use vello_cpu::RenderContext; -use vello_cpu::kurbo::{self, ParamCurve, ParamCurveDeriv}; use vello_cpu::peniko::{self, ColorStop}; fn color(c: &vectorcraft_color::Color, alpha: f32) -> peniko::Color { @@ -54,86 +53,6 @@ pub fn set_paint(ctx: &mut RenderContext, p: &Paint, bounds: Rect, doc: &Documen } } -/// Arrowhead geometry for a stroke: (which, filled outline) in document coordinates. -pub fn arrowheads(bp: &BezPath, st: &StrokeLayer) -> Vec<(Arrowhead, BezPath)> { - let segs: Vec = bp.segments().collect(); - let mut out = Vec::new(); - let (Some(first), Some(last)) = (segs.first(), segs.last()) else { return out }; - if let Some(a) = st.start_arrow { - let p = first.eval(0.0); - let d = tangent(first, 0.0) * -1.0; - out.push((a, head(a, p, d, st.width * st.arrow_scale.0 / 100.0))); - } - if let Some(a) = st.end_arrow { - let p = last.eval(1.0); - let d = tangent(last, 1.0); - out.push((a, head(a, p, d, st.width * st.arrow_scale.1 / 100.0))); - } - out -} - -fn tangent(s: &kurbo::PathSeg, t: f64) -> Vec2 { - let d = match s { - kurbo::PathSeg::Line(l) => l.p1 - l.p0, - kurbo::PathSeg::Quad(q) => q.deriv().eval(t).to_vec2(), - kurbo::PathSeg::Cubic(c) => { - let v = c.deriv().eval(t).to_vec2(); - if v.hypot() < 1e-9 { c.p3 - c.p0 } else { v } - } - }; - let l = d.hypot(); - if l < 1e-12 { Vec2::new(1.0, 0.0) } else { d / l } -} - -/// Arrowhead outline pointing along `dir` with its tip at `tip`, sized for stroke weight `w`. -fn head(kind: Arrowhead, tip: Point, dir: Vec2, w: f64) -> BezPath { - let w = w.max(0.25); - let n = Vec2::new(-dir.y, dir.x); - let len = 4.0 * w; - let half = 2.0 * w; - let base = tip - dir * len; - let mut p = BezPath::new(); - match kind { - Arrowhead::Triangle | Arrowhead::TriangleOpen | Arrowhead::Arrow | Arrowhead::ArrowOpen => { - p.move_to(tip); - p.line_to(base + n * half); - if matches!(kind, Arrowhead::Arrow | Arrowhead::ArrowOpen) { - p.line_to(tip - dir * (len * 0.7)); - } - p.line_to(base - n * half); - p.close_path(); - } - Arrowhead::Circle | Arrowhead::CircleOpen => { - p = kurbo::Circle::new(tip - dir * half, half).to_path(0.01); - } - Arrowhead::Square | Arrowhead::SquareOpen => { - let c = tip - dir * half; - p.move_to(c + dir * half + n * half); - p.line_to(c - dir * half + n * half); - p.line_to(c - dir * half - n * half); - p.line_to(c + dir * half - n * half); - p.close_path(); - } - Arrowhead::Diamond => { - let c = tip - dir * half; - p.move_to(tip); - p.line_to(c + n * half); - p.line_to(c - dir * half); - p.line_to(c - n * half); - p.close_path(); - } - Arrowhead::Bar => { - let t = w * 0.75; - p.move_to(tip + n * half); - p.line_to(tip + n * half - dir * t); - p.line_to(tip - n * half - dir * t); - p.line_to(tip - n * half); - p.close_path(); - } - } - p -} - /// Decode encoded image bytes into a premultiplied pixmap. pub fn decode_pixmap(bytes: &[u8]) -> Option { let img = image::load_from_memory(bytes).ok()?.to_rgba8(); diff --git a/crates/render/src/tests.rs b/crates/render/src/tests.rs index 6fe81b0a..4a8aff07 100644 --- a/crates/render/src/tests.rs +++ b/crates/render/src/tests.rs @@ -202,8 +202,9 @@ fn arrowheads_render() { let l = d.layers[0].id; d.insert(Some(l), 0, n).unwrap(); let r = render(&d); - // Arrowhead is wider than the 2 pt line. - assert!(r.pixel(73, 47)[0] < 128); + // The arrowhead (past the end point by default: tip at 84) is wider than the 2 pt line. + assert!(r.pixel(78, 48)[0] < 128); + assert!(r.pixel(85, 50)[0] > 200, "nothing past the tip"); } use vectorcraft_doc::Arrowhead; diff --git a/crates/render/tests/stroke_geometry.rs b/crates/render/tests/stroke_geometry.rs new file mode 100644 index 00000000..80f326e1 --- /dev/null +++ b/crates/render/tests/stroke_geometry.rs @@ -0,0 +1,184 @@ +//! Pixel tests for the shared stroke geometry (`vectorcraft_effects::stroke`) on the canvas: +//! dotted lines (zero-length dashes) and arrowheads (hollow kinds, alignment, compositing). + +use vectorcraft_color::{Color, Gradient, GradientKind, GradientPaint, GradientStop, Paint}; +use vectorcraft_doc::{Appearance, AppearanceItem, ArrowAlign, Arrowhead, Dash, Document, LineCap, StrokeLayer}; +use vectorcraft_geom::{Point, Rect, Shape, shapes}; +use vectorcraft_render::{Renderer, effects}; +use vectorcraft_testkit::fixtures::DocBuilder; +use vectorcraft_testkit::raster::{Image, assert_similar, render_region}; +use vectorcraft_testkit::svg; + +/// Pixels per point in these tests. +const S: f64 = 4.0; + +fn stroked(width: f64, f: impl FnOnce(&mut StrokeLayer)) -> Appearance { + let mut st = StrokeLayer::new(Paint::solid(Color::BLACK), width); + f(&mut st); + Appearance { items: vec![AppearanceItem::Stroke(st)], effects: vec![] } +} + +/// A horizontal line from x0 to x1 at y = 50 on a 100 × 100 artboard. +fn line_doc(x0: f64, x1: f64, app: Appearance, opacity: f32) -> Document { + let mut b = DocBuilder::new(100.0, 100.0); + b.path(shapes::line(Point::new(x0, 50.0), Point::new(x1, 50.0)), app, |n| n.opacity = opacity); + b.build() +} + +fn render(d: &Document) -> Image { + render_region(d, Rect::new(0.0, 0.0, 100.0, 100.0), S) +} + +/// Is the pixel at document point (x, y) dark? +fn dark(img: &Image, x: f64, y: f64) -> bool { + img.over_white((x * S) as u32, (y * S) as u32)[0] < 128 +} + +fn dotted(cap: LineCap) -> Document { + line_doc( + 20.0, + 80.0, + stroked(4.0, |s| { + s.cap = cap; + s.dash = Some(Dash { pattern: vec![0.0, 6.0], offset: 0.0, align_corners: false }); + }), + 1.0, + ) +} + +#[test] +fn zero_length_dashes_draw_dots_with_a_round_cap_and_squares_with_a_projecting_cap() { + let round = render(&dotted(LineCap::Round)); + // 60 pt with a dot every 6 pt: 11 separate dots along the centre line. + let row: Vec = (0..round.width).map(|x| round.over_white(x, (50.0 * S) as u32)[0] < 128).collect(); + let runs = row.windows(2).filter(|w| !w[0] && w[1]).count(); + assert_eq!(runs, 11, "dots along the line"); + for k in 0..=10 { + let x = 20.0 + 6.0 * k as f64; + assert!(dark(&round, x, 50.0), "dot {k}"); + assert!(!dark(&round, x + 3.0, 50.0), "gap after dot {k}"); + } + // A disc's corner region is empty; a square fills it. + assert!(!dark(&round, 20.0 + 1.8, 50.0 + 1.8)); + let square = render(&dotted(LineCap::Square)); + assert!(dark(&square, 20.0 + 1.8, 50.0 + 1.8)); + assert!(dark(&square, 26.0 - 1.8, 50.0 - 1.8)); + // A butt cap gives a zero-length dash no area at all. + assert_eq!(render(&dotted(LineCap::Butt)).ink(), 0); +} + +#[test] +fn dotted_lines_survive_svg_export_and_render_the_same() { + for cap in [LineCap::Round, LineCap::Square] { + let d = dotted(cap); + let text = svg::export(&d, &Default::default()); + let back = svg::import(&text).unwrap(); + assert_similar(&render(&d), &render(&back), 0.05, 0.001); + } +} + +fn arrow_doc(kind: Arrowhead, align: ArrowAlign, opacity: f32, f: impl FnOnce(&mut StrokeLayer)) -> Document { + line_doc( + 20.0, + 80.0, + stroked(4.0, |s| { + s.end_arrow = Some(kind); + s.arrow_align = align; + f(s); + }), + opacity, + ) +} + +/// The arrowhead the shared geometry computes for the line of `d`. +fn head_of(d: &Document) -> effects::stroke::Arrow { + let n = d.layers[0].children().unwrap()[0].clone(); + let bp = n.path_data().unwrap().to_bezpath(); + effects::stroke::stroke_pieces(&bp, n.appearance.stroke().unwrap()).heads.remove(0) +} + +#[test] +fn a_hollow_circle_head_is_empty_inside() { + let d = arrow_doc(Arrowhead::CircleOpen, ArrowAlign::Extend, 1.0, |_| {}); + let h = head_of(&d); + let centre = h.tip - h.dir * 8.0; + let img = render(&d); + assert!(!dark(&img, centre.x, centre.y), "the centre of an open circle is empty"); + assert!(dark(&img, h.tip.x - 1.0, 50.0), "its wall is painted"); + // The filled circle is solid. + let solid = render(&arrow_doc(Arrowhead::Circle, ArrowAlign::Extend, 1.0, |_| {})); + assert!(dark(&solid, centre.x, centre.y)); +} + +#[test] +fn heads_are_drawn_where_the_shared_geometry_puts_them_and_never_past_the_tip() { + for align in [ArrowAlign::Extend, ArrowAlign::Tip] { + for kind in Arrowhead::ALL { + let d = arrow_doc(kind, align, 1.0, |s| s.cap = LineCap::Round); + let h = head_of(&d); + if align == ArrowAlign::Tip { + assert_eq!(h.tip, Point::new(80.0, 50.0)); + } else { + assert!((h.tip.x - (80.0 + h.inset)).abs() < 1e-9); + } + let img = render(&d); + // The rightmost ink is the tip (allowing for antialiasing). + let right = (0..img.width).rev().find(|&x| (0..img.height).any(|y| img.over_white(x, y)[0] < 250)).unwrap(); + let bb = h.outline.bounding_box(); + assert!((right as f64 / S - bb.x1).abs() <= 0.5, "{kind:?} {align:?}: ink ends at {} vs head {}", right as f64 / S, bb.x1); + assert!(!dark(&img, h.tip.x + 0.5, 50.0), "{kind:?} {align:?}: nothing past the tip"); + } + } +} + +/// Straight-alpha pixel at document point (x, y), rendered on transparent. +fn alpha_at(d: &Document, x: f64, y: f64) -> u8 { + let r = Renderer::new().render_region(d, Rect::new(0.0, 0.0, 100.0, 100.0), S, false); + r.pixel((x * S) as u32, (y * S) as u32)[3] +} + +#[test] +fn line_and_head_take_the_opacity_once() { + for (node, stroke) in [(0.5, 1.0), (1.0, 0.5)] { + let d = arrow_doc(Arrowhead::Triangle, ArrowAlign::Extend, node, |s| s.opacity = stroke); + let h = head_of(&d); + let line = alpha_at(&d, 40.0, 50.0); + assert!((120..=135).contains(&line), "half-opaque line: {line}"); + // Where the line runs under the head, and in the head beside it. + let overlap = alpha_at(&d, h.tip.x - h.inset - 1.0, 50.0); + let beside = alpha_at(&d, h.tip.x - 12.0, 50.0 + 4.5); + assert_eq!(overlap, line, "no double darkening where line and head overlap"); + assert_eq!(beside, line, "the head has the line's opacity"); + } +} + +#[test] +fn a_gradient_runs_on_into_the_head() { + let stops = vec![ + GradientStop { offset: 0.0, color: Color::rgb(1.0, 0.0, 0.0), opacity: 1.0, midpoint: 0.5 }, + GradientStop { offset: 1.0, color: Color::rgb(0.0, 0.0, 1.0), opacity: 1.0, midpoint: 0.5 }, + ]; + let paint = Paint::Gradient(Box::new(GradientPaint::new(Gradient { kind: GradientKind::Linear, stops }))); + let d = arrow_doc(Arrowhead::Square, ArrowAlign::Tip, 1.0, |s| s.paint = paint); + let h = head_of(&d); + let img = render(&d); + // Just behind the head's back edge (line) and just inside it (head): nearly the same colour. + let back = h.tip.x - 16.0; + let (a, b) = (img.over_white(((back - 0.5) * S) as u32, (50.0 * S) as u32), img.over_white(((back + 0.5) * S) as u32, (50.0 * S) as u32)); + assert!(a[0].abs_diff(b[0]) < 12 && a[2].abs_diff(b[2]) < 12, "{a:?} vs {b:?}"); + // The head is part of the same gradient: bluer than the line's start. + let start = img.over_white((22.0 * S) as u32, (50.0 * S) as u32); + assert!(b[2] > start[2] + 100, "{b:?} vs {start:?}"); +} + +#[test] +fn a_head_past_the_end_counts_in_the_visual_bounds_and_is_never_culled() { + let d = arrow_doc(Arrowhead::Triangle, ArrowAlign::Extend, 1.0, |s| s.join = vectorcraft_doc::LineJoin::Round); + let h = head_of(&d); + let vb = d.layers[0].children().unwrap()[0].visual_bounds().unwrap(); + let head = h.outline.bounding_box(); + assert_eq!(vb.union(head), vb, "{vb:?} covers the head {head:?}"); + // A view that shows only the overhanging part of the head (the line ends at 80). + let img = render_region(&d, Rect::new(83.0, 40.0, 100.0, 60.0), S); + assert!(img.ink() > 0, "the head is drawn"); +} diff --git a/crates/ui-egui/src/icon_data.rs b/crates/ui-egui/src/icon_data.rs index 64f2ceb7..c3f309dc 100644 --- a/crates/ui-egui/src/icon_data.rs +++ b/crates/ui-egui/src/icon_data.rs @@ -44,6 +44,8 @@ pub static ICONS: &[(&str, &[u8])] = &[ ("dc-appearance", include_bytes!("../../../assets/icons/dc-appearance.svg")), ("dc-arc", include_bytes!("../../../assets/icons/dc-arc.svg")), ("dc-arrow-down", include_bytes!("../../../assets/icons/dc-arrow-down.svg")), + ("dc-arrow-extend", include_bytes!("../../../assets/icons/dc-arrow-extend.svg")), + ("dc-arrow-tip", include_bytes!("../../../assets/icons/dc-arrow-tip.svg")), ("dc-arrow-up", include_bytes!("../../../assets/icons/dc-arrow-up.svg")), ("dc-artboard-options", include_bytes!("../../../assets/icons/dc-artboard-options.svg")), ("dc-artboards", include_bytes!("../../../assets/icons/dc-artboards.svg")), diff --git a/crates/ui-egui/src/panels/stroke.rs b/crates/ui-egui/src/panels/stroke.rs index 90b456c5..e9a466d0 100644 --- a/crates/ui-egui/src/panels/stroke.rs +++ b/crates/ui-egui/src/panels/stroke.rs @@ -3,7 +3,7 @@ use egui::{Color32, Pos2, Rect, Sense, Stroke, StrokeKind, Ui, pos2, vec2}; use serde_json::{Value, json}; -use vectorcraft_doc::{Arrowhead, LineCap, LineJoin, StrokeAlign, StrokeLayer, Unit, WidthProfile}; +use vectorcraft_doc::{ArrowAlign, Arrowhead, LineCap, LineJoin, ProfilePreset, StrokeAlign, StrokeLayer, Unit, WidthProfile}; use super::{first_selected, pstate, set_pstate}; use crate::theme::Tokens; @@ -13,27 +13,20 @@ use crate::{VectorcraftApp, icons}; pub const WEIGHT_PRESETS: [f64; 22] = [0.25, 0.5, 0.75, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 20.0, 30.0, 40.0, 50.0, 60.0, 70.0, 80.0, 90.0, 100.0]; -/// Width profile presets: (id for `stroke.set`, label). -pub const PROFILES: [(&str, &str); 4] = [("uniform", "Uniform"), ("lens", "Lens"), ("taperStart", "Taper Start"), ("taperEnd", "Taper End")]; - -/// Which preset a stroke's profile is (None profile = uniform). -pub fn profile_id(p: Option<&WidthProfile>) -> &'static str { - let Some(p) = p else { return "uniform" }; - for (id, prof) in [("lens", WidthProfile::lens()), ("taperStart", WidthProfile::taper_start()), ("taperEnd", WidthProfile::taper_end())] { - if prof.points == p.points { - return id; - } - } - "custom" +/// The silhouette drawn for profile `id` (None draws the plain uniform bar). +fn profile_of(id: &str) -> Option { + WidthProfile::preset(id).filter(|_| id != "uniform") } -fn profile_of(id: &str) -> Option { - match id { - "lens" => Some(WidthProfile::lens()), - "taperStart" => Some(WidthProfile::taper_start()), - "taperEnd" => Some(WidthProfile::taper_end()), - _ => None, - } +/// The Arrowheads Align buttons: (alignment, `stroke.set` value, icon, tooltip). +const ARROW_ALIGN: [(ArrowAlign, &str, &str, &str); 2] = [ + (ArrowAlign::Extend, "extend", "dc-arrow-extend", "Tip extends past the end point"), + (ArrowAlign::Tip, "tip", "dc-arrow-tip", "Tip on the end point"), +]; + +/// Which Align button is on, and whether they are usable (only a stroke with a head can be aligned). +fn arrow_align_state(st: Option<&StrokeLayer>) -> (ArrowAlign, bool) { + st.map_or((ArrowAlign::default(), false), |s| (s.arrow_align, s.start_arrow.is_some() || s.end_arrow.is_some())) } /// Dash pattern → the panel's six dash/gap fields (None = empty field). @@ -211,11 +204,12 @@ pub fn show(app: &mut VectorcraftApp, ui: &mut Ui) { }); let scale = st.as_ref().map(|s| s.arrow_scale).unwrap_or((100.0, 100.0)); let linked: bool = pstate(ui.ctx(), "arrow-scale-link"); + // Scale and Align only mean something for a stroke with a head. + let (arrow_align, has_head) = arrow_align_state(st.as_ref()); ui.horizontal(|ui| { row_label(ui, "Scale:"); - let on = st.is_some() && (sa.is_some() || ea.is_some()); let mut ns = None; - ui.add_enabled_ui(on, |ui| { + ui.add_enabled_ui(has_head, |ui| { if let Some(v) = widgets::plain_field(ui, "arrow-scale-s", scale.0, "%", 0, 56.0) { ns = Some((v, if linked { v } else { scale.1 })); } @@ -232,12 +226,15 @@ pub fn show(app: &mut VectorcraftApp, ui: &mut Ui) { }); ui.horizontal(|ui| { row_label(ui, "Align:"); - widgets::icon_button_enabled(ui, "dc-cap-square", "Tip extends past the end (on the roadmap)", true, false, 22.0); - widgets::icon_button_enabled(ui, "dc-cap-butt", "Tip on the end point (on the roadmap)", false, false, 22.0); + for (v, name, icon, tip) in ARROW_ALIGN { + if widgets::icon_button_enabled(ui, icon, tip, arrow_align == v, has_head, 22.0).clicked() { + set(app, json!({"arrowAlign": name})); + } + } }); widgets::divider(ui); // Profile. - let pid = profile_id(st.as_ref().and_then(|s| s.profile.as_ref())); + let pid = WidthProfile::id_of(st.as_ref().and_then(|s| s.profile.as_ref())); ui.horizontal(|ui| { row_label(ui, "Profile:"); if let Some(id) = profile_dropdown(ui, pid) { @@ -355,7 +352,7 @@ fn profile_dropdown(ui: &mut Ui, cur: &str) -> Option<&'static str> { let resp = resp.on_hover_text("Variable Width Profile"); let mut out = None; egui::Popup::menu(&resp).show(|ui| { - for (id, label) in PROFILES { + for ProfilePreset { id, label, .. } in WidthProfile::PRESETS { let (row, rr) = ui.allocate_exact_size(vec2(170.0, 26.0), Sense::click()); if id == cur { ui.painter().rect_filled(row, 0.0, t.row_selected); @@ -404,11 +401,51 @@ mod tests { } #[test] - fn profile_ids() { - assert_eq!(profile_id(None), "uniform"); - assert_eq!(profile_id(Some(&WidthProfile::lens())), "lens"); - assert_eq!(profile_id(Some(&WidthProfile::taper_end())), "taperEnd"); - assert_eq!(profile_id(Some(&WidthProfile { points: vec![(0.0, 0.3, 0.3)] })), "custom"); + fn profile_silhouettes_and_arrow_labels() { + assert!(profile_of("uniform").is_none()); + assert_eq!(profile_of("lens"), Some(WidthProfile::lens())); + assert!(profile_of("custom").is_none()); assert_eq!(arrow_label(Some(Arrowhead::CircleOpen)), "Circle (open)"); } + + #[test] + fn arrow_align_buttons_need_a_head() { + let mut st = StrokeLayer::new(vectorcraft_color::Paint::None, 1.0); + assert_eq!(arrow_align_state(None), (ArrowAlign::Extend, false)); + assert_eq!(arrow_align_state(Some(&st)), (ArrowAlign::Extend, false)); + st.start_arrow = Some(Arrowhead::Bar); + st.arrow_align = ArrowAlign::Tip; + assert_eq!(arrow_align_state(Some(&st)), (ArrowAlign::Tip, true)); + for (_, _, icon, _) in ARROW_ALIGN { + assert!(icons::exists(icon), "{icon}"); + } + } + + /// Run the panel and its ≡ menu for one headless frame. + fn frame(app: &mut VectorcraftApp) { + let ctx = egui::Context::default(); + let mut out = ctx.run_ui(egui::RawInput::default(), |ui| { + show(app, ui); + menu(app, ui); + }); + out.textures_delta.clear(); + } + + #[test] + fn panel_draws_for_lines_with_and_without_heads() { + use vectorcraft_engine::Session; + let mut app = VectorcraftApp::new(Session::new(), Default::default()); + let r = |app: &mut VectorcraftApp, id: &str, p: Value| app.session.execute(id, &p).unwrap(); + r(&mut app, "file.new", json!({"width": 100, "height": 100})); + frame(&mut app); + r(&mut app, "shape.line", json!({"x1": 10, "y1": 50, "x2": 90, "y2": 50})); + frame(&mut app); + for p in [json!({"endArrow": "ArrowOpen", "arrowAlign": "tip"}), json!({"profile": "lens"}), json!({"dash": [0, 6], "cap": "round"})] { + r(&mut app, "stroke.set", p); + frame(&mut app); + } + let st = stroke_now(&app).unwrap(); + assert_eq!((st.end_arrow, st.arrow_align), (Some(Arrowhead::ArrowOpen), ArrowAlign::Tip)); + assert_eq!(WidthProfile::id_of(st.profile.as_ref()), "lens"); + } } diff --git a/crates/ui-egui/src/tests_labels.rs b/crates/ui-egui/src/tests_labels.rs index f17a0d6a..7907abce 100644 --- a/crates/ui-egui/src/tests_labels.rs +++ b/crates/ui-egui/src/tests_labels.rs @@ -56,7 +56,7 @@ fn library_submenus_are_disabled_placeholders() { #[test] fn stroke_profiles_have_descriptive_names() { - let labels: Vec<&str> = crate::panels::stroke::PROFILES.iter().map(|p| p.1).collect(); + let labels: Vec<&str> = vectorcraft_doc::WidthProfile::PRESETS.iter().map(|p| p.label).collect(); assert_eq!(labels, ["Uniform", "Lens", "Taper Start", "Taper End"]); }