1640 lines
65 KiB
Rust
1640 lines
65 KiB
Rust
//! Live blends, envelope distortions and gradient meshes: their data and pure evaluation.
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//!
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//! These are *live* objects. The document stores the source objects plus parameters; the
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//! renderer and the exporters evaluate them on demand ([`expand_live`], [`expand_deep`]).
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//! Everything here is pure geometry so the SVG/PDF exporters (which only depend on this crate)
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//! can export the expanded form.
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//!
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//! - **Blend**: key objects are matched anchor-by-anchor (subpaths resampled to equal anchor
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//! counts), paints/strokes/opacity interpolated; optional spine (keys spread along it by arc
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//! length, optionally rotated to its tangent).
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//! - **Envelope**: all descendant geometry of the content is pushed through a point map from the
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//! content's bounding box to a warp style, a Catmull-Rom point mesh or a top object (Coons
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//! patch built from the top path's outline split at its corners).
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//! - **Gradient mesh**: a grid of points with colours and tangent handles; each patch is a Coons
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//! patch coloured by bilinear interpolation of its four corners.
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use std::f64::consts::PI;
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use std::sync::Arc;
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use serde::{Deserialize, Serialize};
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use vectorcraft_color::{Color, Paint};
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use vectorcraft_geom::{Affine, Anchor, BezPath, CubicBez, ParamCurve, PathData, Point, Rect, Shape, SubPath, Vec2};
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use crate::appearance::{Appearance, AppearanceItem, FillLayer};
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use crate::node::{ImageObject, Node, NodeId, NodeKind};
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fn yes() -> bool {
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true
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}
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fn one() -> f32 {
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1.0
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}
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fn fifty() -> f64 {
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50.0
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}
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// =====================================================================================
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// Data
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// =====================================================================================
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/// Blend Options → Spacing.
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#[derive(Clone, Copy, Debug, Default, PartialEq, Serialize, Deserialize)]
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#[serde(rename_all = "camelCase")]
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pub enum BlendSpacing {
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/// Step count chosen from the colour difference (or the distance when colours match).
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#[default]
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SmoothColor,
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/// Specified number of steps between each pair of key objects (1–1000).
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Steps(u32),
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/// Specified distance (pt) between the steps.
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Distance(f64),
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}
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/// Blend Options → Orientation.
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#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
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#[serde(rename_all = "camelCase")]
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pub enum BlendOrientation {
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#[default]
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AlignToPage,
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AlignToPath,
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}
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#[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)]
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pub struct BlendSpec {
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#[serde(default)]
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pub spacing: BlendSpacing,
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#[serde(default)]
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pub orientation: BlendOrientation,
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/// Replaced spine. `None` = the straight lines between the key objects' centres.
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#[serde(default, skip_serializing_if = "Option::is_none")]
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pub spine: Option<PathData>,
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/// The anchor of the spine's first subpath each key object sits on (a spine edited on the
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/// canvas: moving a key moves its anchor and the other way round). Empty: the keys spread
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/// evenly along the spine by arc length (Replace Spine).
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#[serde(default, rename = "keyAnchors", skip_serializing_if = "Vec::is_empty")]
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pub key_anchors: Vec<u32>,
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/// Per key object, the anchor of its first subpath the blend starts from (Blend tool clicks
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/// on anchor points); `None`: chosen so closed shapes don't twist.
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#[serde(default, skip_serializing_if = "Vec::is_empty")]
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pub starts: Vec<Option<u32>>,
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}
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impl BlendSpec {
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/// The start anchor of key `i` (see [`Self::starts`]).
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pub fn start(&self, i: usize) -> Option<usize> {
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self.starts.get(i).copied().flatten().map(|a| a as usize)
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}
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}
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/// Blend Options set with no blend selected: what new blends start with.
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#[derive(Clone, Copy, Debug, Default, PartialEq, Serialize, Deserialize)]
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pub struct BlendDefaults {
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#[serde(default)]
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pub spacing: BlendSpacing,
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#[serde(default)]
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pub orientation: BlendOrientation,
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}
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/// How an envelope distorts its content.
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#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
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#[serde(tag = "type", rename_all = "camelCase")]
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pub enum EnvelopeKind {
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/// One of the 15 warp styles (`arc`, `arcLower`, … — see [`WarpStyle::from_id`]); bend and
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/// distortions in percent (-100..100).
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Warp {
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style: String,
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#[serde(default)]
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bend: f64,
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#[serde(default)]
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h: f64,
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#[serde(default)]
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v: f64,
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#[serde(default = "yes")]
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horizontal: bool,
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},
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/// A `(rows+1)×(cols+1)` grid of points (row-major) the content's bounding box maps onto.
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Mesh { rows: u32, cols: u32, points: Vec<Point> },
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/// The content's bounding box maps onto the outline of this path.
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TopObject { path: PathData },
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}
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/// Envelope Options → Preserve Shape Using: how a distorted raster keeps the envelope's shape.
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#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
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#[serde(rename_all = "camelCase")]
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pub enum PreserveShape {
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#[default]
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ClippingMask,
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Transparency,
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}
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impl PreserveShape {
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pub fn id(self) -> &'static str {
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match self {
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Self::ClippingMask => "clippingMask",
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Self::Transparency => "transparency",
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}
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}
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pub fn parse(s: &str) -> Option<Self> {
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match s {
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"clippingMask" => Some(Self::ClippingMask),
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"transparency" => Some(Self::Transparency),
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_ => None,
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}
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}
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}
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/// Envelope Options besides Fidelity. `Default` is what envelopes saved before these options
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/// existed do (their appearance applies after the distortion); new envelopes start from
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/// [`EnvelopeOptions::NEW`], as in the reference app.
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#[derive(Clone, Copy, Debug, PartialEq, Serialize, Deserialize)]
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#[serde(rename_all = "camelCase", default)]
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pub struct EnvelopeOptions {
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/// Rasters: Anti-Alias.
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pub anti_alias: bool,
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/// Rasters: Preserve Shape Using.
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pub preserve_shape: PreserveShape,
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/// Distort Appearance: strokes and live effects are applied before the distortion, so they
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/// bend with the art (off: they apply to the distorted paths).
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pub distort_appearance: bool,
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/// Distort Linear Gradients (with Distort Appearance): placed gradients bend with the art.
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pub distort_linear_gradients: bool,
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/// Distort Pattern Fills (with Distort Appearance): pattern tiles bend with the art.
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pub distort_pattern_fills: bool,
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}
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impl Default for EnvelopeOptions {
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fn default() -> Self {
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Self {
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anti_alias: true,
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preserve_shape: PreserveShape::ClippingMask,
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distort_appearance: false,
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distort_linear_gradients: false,
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distort_pattern_fills: false,
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}
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}
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}
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impl EnvelopeOptions {
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/// The options a new envelope gets (the reference app's defaults).
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pub const NEW: Self = Self {
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anti_alias: true,
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preserve_shape: PreserveShape::ClippingMask,
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distort_appearance: true,
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distort_linear_gradients: false,
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distort_pattern_fills: false,
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};
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/// Do gradients bend with the art?
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pub fn gradients(&self) -> bool {
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self.distort_appearance && self.distort_linear_gradients
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}
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/// Do pattern tiles bend with the art?
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pub fn patterns(&self) -> bool {
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self.distort_appearance && self.distort_pattern_fills
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}
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}
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/// Handle slots of a [`MeshPoint`]: towards the next column, previous column, next row, previous row.
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pub const H_RIGHT: usize = 0;
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pub const H_LEFT: usize = 1;
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pub const H_DOWN: usize = 2;
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pub const H_UP: usize = 3;
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#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
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pub struct MeshPoint {
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pub p: Point,
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pub color: Color,
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#[serde(default = "one")]
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pub opacity: f32,
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/// Tangent handles as offsets from `p` (see [`H_RIGHT`] …).
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#[serde(default)]
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pub handles: [Vec2; 4],
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}
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/// A gradient mesh: `(rows+1)×(cols+1)` points, row-major.
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#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
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pub struct GradientMesh {
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pub rows: u32,
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pub cols: u32,
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pub points: Vec<MeshPoint>,
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}
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/// One tessellated piece of a mesh (a small quad with a solid colour).
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#[derive(Clone, Copy, Debug, PartialEq)]
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pub struct MeshQuad {
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pub pts: [Point; 4],
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pub color: Color,
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pub opacity: f32,
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}
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/// Create Gradient Mesh → Appearance.
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#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
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pub enum MeshAppearance {
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#[default]
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Flat,
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ToCenter,
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ToEdge,
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}
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impl MeshAppearance {
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pub fn parse(s: &str) -> Option<Self> {
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match s.to_ascii_lowercase().as_str() {
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"flat" => Some(Self::Flat),
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"center" | "tocenter" | "to center" => Some(Self::ToCenter),
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"edge" | "toedge" | "to edge" => Some(Self::ToEdge),
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_ => None,
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}
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}
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}
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/// Default envelope fidelity.
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pub fn default_fidelity() -> f64 {
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fifty()
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}
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// =====================================================================================
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// Blends (evaluation in `crate::blend`)
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// =====================================================================================
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pub use crate::blend::{
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Spine, blend_expand, blend_spine, blend_step_count, lerp_appearance, lerp_color, lerp_node, lerp_paint, lerp_path, pin_spine,
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steps_knockout_shows,
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};
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// =====================================================================================
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// Warp maps (shared with vectorcraft-effects' Warp effects)
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// =====================================================================================
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#[derive(Clone, Copy, Debug, PartialEq, Eq)]
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pub enum WarpStyle {
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Arc,
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ArcLower,
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ArcUpper,
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Arch,
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Bulge,
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ShellLower,
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ShellUpper,
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Flag,
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Wave,
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Fish,
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Rise,
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Fisheye,
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Inflate,
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Squeeze,
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Twist,
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}
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impl WarpStyle {
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/// From the id suffix (`arc`, `arcLower`, …).
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pub fn from_id(s: &str) -> Option<Self> {
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use WarpStyle::*;
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Some(match s {
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"arc" => Arc,
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"arcLower" => ArcLower,
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"arcUpper" => ArcUpper,
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"arch" => Arch,
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"bulge" => Bulge,
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"shellLower" => ShellLower,
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"shellUpper" => ShellUpper,
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"flag" => Flag,
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"wave" => Wave,
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"fish" => Fish,
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"rise" => Rise,
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"fisheye" => Fisheye,
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"inflate" => Inflate,
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"squeeze" => Squeeze,
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"twist" => Twist,
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_ => return None,
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})
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}
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}
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/// The warp map on normalised coordinates: `b` = bend (-1..1), `dh`/`dv` = distortion (-1..1).
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pub fn warp_point(style: WarpStyle, b: f64, dh: f64, dv: f64, x: f64, y: f64) -> (f64, f64) {
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use WarpStyle::*;
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let t = (y + 1.0) / 2.0; // 0 at top, 1 at bottom
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let par = 1.0 - x * x; // parabola: 1 at centre, 0 at sides
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let (mut x2, mut y2) = match style {
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Arc => {
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if b.abs() < 1e-6 {
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(x, y)
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} else {
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// Bend the centre line into a circular arc of equal length (sweep = |b|·180°).
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let sweep = b.abs() * PI;
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let r0 = 2.0 / sweep;
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let yy = if b > 0.0 { y } else { -y };
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let a = x / r0;
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let r = r0 - yy;
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let (s, c) = a.sin_cos();
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let (nx, ny) = (r * s, r0 - r * c);
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(nx, if b > 0.0 { ny } else { -ny })
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}
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}
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ArcLower => (x, y + b * par * t),
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ArcUpper => (x, y - b * par * (1.0 - t)),
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Arch => (x, y - b * par),
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Bulge => (x, y + b * par * y),
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ShellLower => (x * (1.0 - 0.5 * b * (1.0 - t)), y + b * par * t),
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ShellUpper => (x * (1.0 - 0.5 * b * t), y - b * par * (1.0 - t)),
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Flag => (x, y + 0.5 * b * (PI * x).sin()),
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Wave => (x + 0.1 * b * (PI * y).sin(), y + 0.3 * b * (2.0 * PI * x).sin() * (0.5 + 0.5 * t)),
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Fish => (x, y * (1.0 + 0.5 * b * (0.75 * PI * (x + 1.0)).sin())),
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Rise => (x, y - b * ((x + 1.0) / 2.0).powi(2) * 2.0 + b),
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Fisheye => {
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let r2 = x * x + y * y;
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let s = if r2 < 1.0 { 1.0 + 0.5 * b * (1.0 - r2) } else { 1.0 };
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(x * s, y * s)
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}
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Inflate => (x * (1.0 + 0.5 * b * (1.0 - y * y)), y * (1.0 + 0.5 * b * par)),
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Squeeze => (x * (1.0 - 0.5 * b * (1.0 - y * y)), y * (1.0 + 0.3 * b * par)),
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Twist => {
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let r = (x * x + y * y).sqrt();
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let a = -b * PI * 0.5 * (1.0 - r / std::f64::consts::SQRT_2).max(0.0);
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let (s, c) = a.sin_cos();
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(x * c - y * s, x * s + y * c)
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}
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};
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// Perspective-like distortion: horizontal narrows one side, vertical one end.
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if dh != 0.0 {
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y2 *= (1.0 + dh * x2 * 0.5).max(0.0);
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}
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if dv != 0.0 {
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x2 *= (1.0 + dv * y2 * 0.5).max(0.0);
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}
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(x2, y2)
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}
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/// Segment as a cubic; straight lines get handles at 1/3 and 2/3 so a non-linear map bends them.
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fn seg_cubic(sp: &SubPath, i: usize) -> CubicBez {
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let c = sp.segment(i);
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if sp.segment_is_line(i) { CubicBez::new(c.p0, c.p0.lerp(c.p3, 1.0 / 3.0), c.p0.lerp(c.p3, 2.0 / 3.0), c.p3) } else { c }
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}
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fn poly_len(c: &CubicBez) -> f64 {
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c.p0.distance(c.p1) + c.p1.distance(c.p2) + c.p2.distance(c.p3)
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}
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/// Running length along a polyline: `0, |p0p1|, |p0p1| + |p1p2|, …` (one entry per point).
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fn cumulative_lengths(pts: &[Point]) -> Vec<f64> {
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let mut total = 0.0;
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let mut cum = Vec::with_capacity(pts.len());
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cum.push(0.0);
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for w in pts.windows(2) {
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total += w[0].distance(w[1]);
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cum.push(total);
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}
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cum
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}
|
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/// Map every point of `path` through the non-linear function `f`. Segments are split into pieces
|
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/// no longer than about `max_piece` (up to 64 per segment) and their control points mapped, which
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/// approximates the image curve to O(h²). Closedness and subpath structure are preserved.
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pub fn map_nonlinear(path: &PathData, max_piece: f64, f: impl Fn(Point) -> Point) -> PathData {
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let max_piece = max_piece.max(1e-3);
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let mut subs = Vec::with_capacity(path.subpaths.len());
|
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for sp in &path.subpaths {
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let n = sp.anchors.len();
|
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if n == 0 {
|
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continue;
|
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}
|
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let segs = sp.segment_count();
|
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let mut res: Vec<Anchor> = Vec::new();
|
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let mut pending_in: Option<Point> = None;
|
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for i in 0..n {
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let a = &sp.anchors[i];
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let h_in = pending_in.take().unwrap_or_else(|| f(a.h_in));
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res.push(Anchor { p: f(a.p), h_in, h_out: f(a.h_out), kind: a.kind });
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if i < segs {
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let c = seg_cubic(sp, i);
|
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let k = ((poly_len(&c) / max_piece).ceil() as usize).clamp(1, 64);
|
||
for j in 0..k {
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let sub = c.subsegment((j as f64 / k as f64)..((j + 1) as f64 / k as f64));
|
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if let Some(last) = res.last_mut() {
|
||
last.h_out = f(sub.p1);
|
||
}
|
||
if j + 1 < k {
|
||
res.push(Anchor { p: f(sub.p3), h_in: f(sub.p2), h_out: f(sub.p3), kind: Default::default() });
|
||
} else {
|
||
pending_in = Some(f(sub.p2));
|
||
}
|
||
}
|
||
}
|
||
}
|
||
if let Some(h) = pending_in
|
||
&& sp.closed
|
||
&& let Some(first) = res.first_mut()
|
||
{
|
||
first.h_in = h;
|
||
}
|
||
let anchors = res.into_iter().map(|a| Anchor::with_handles(a.p, a.h_in, a.h_out)).collect();
|
||
subs.push(SubPath::new(anchors, sp.closed));
|
||
}
|
||
PathData::new(subs)
|
||
}
|
||
|
||
// =====================================================================================
|
||
// Coons patches from outlines
|
||
// =====================================================================================
|
||
|
||
fn flatten_subpath(sp: &SubPath, tol: f64) -> Vec<Point> {
|
||
let mut bp = BezPath::new();
|
||
sp.to_bezpath_into(&mut bp);
|
||
let mut pts: Vec<Point> = Vec::new();
|
||
vectorcraft_geom::kurbo::flatten(bp.iter(), tol, |el| match el {
|
||
vectorcraft_geom::PathEl::MoveTo(p) | vectorcraft_geom::PathEl::LineTo(p) if pts.last().is_none_or(|q| q.distance(p) > 1e-9) => pts.push(p),
|
||
_ => {}
|
||
});
|
||
pts
|
||
}
|
||
|
||
fn resample(poly: &[Point], m: usize) -> Vec<Point> {
|
||
if poly.is_empty() {
|
||
return vec![Point::ZERO; m];
|
||
}
|
||
if poly.len() == 1 {
|
||
return vec![poly[0]; m];
|
||
}
|
||
let cum = cumulative_lengths(poly);
|
||
let total = cum.last().copied().unwrap_or(0.0);
|
||
let mut out = Vec::with_capacity(m);
|
||
let mut i = 0;
|
||
for k in 0..m {
|
||
let s = if m > 1 { total * k as f64 / (m - 1) as f64 } else { 0.0 };
|
||
while i + 2 < cum.len() && cum[i + 1] < s {
|
||
i += 1;
|
||
}
|
||
let seg = (cum[i + 1] - cum[i]).max(1e-12);
|
||
out.push(poly[i].lerp(poly[i + 1], ((s - cum[i]) / seg).clamp(0.0, 1.0)));
|
||
}
|
||
out
|
||
}
|
||
|
||
const SIDE: usize = 65;
|
||
|
||
/// Four boundary curves (top TL→TR, right TR→BR, bottom BL→BR, left TL→BL), each resampled to
|
||
/// [`SIDE`] points, from the outline of a closed path split at the points nearest its bounding
|
||
/// box corners.
|
||
#[derive(Clone, Debug)]
|
||
pub struct Coons {
|
||
top: Vec<Point>,
|
||
right: Vec<Point>,
|
||
bottom: Vec<Point>,
|
||
left: Vec<Point>,
|
||
}
|
||
|
||
impl Coons {
|
||
/// A rectangle.
|
||
pub fn rect(r: Rect) -> Self {
|
||
let line = |a: Point, b: Point| (0..SIDE).map(|i| a.lerp(b, i as f64 / (SIDE - 1) as f64)).collect::<Vec<_>>();
|
||
let (tl, tr, br, bl) = (Point::new(r.x0, r.y0), Point::new(r.x1, r.y0), Point::new(r.x1, r.y1), Point::new(r.x0, r.y1));
|
||
Self { top: line(tl, tr), right: line(tr, br), bottom: line(bl, br), left: line(tl, bl) }
|
||
}
|
||
|
||
pub fn from_path(path: &PathData) -> Option<Self> {
|
||
// The largest subpath is the outline.
|
||
let sp = path.subpaths.iter().filter(|s| s.anchors.len() >= 2).max_by(|a, b| a.area().abs().total_cmp(&b.area().abs()))?;
|
||
let r = path.bounds()?;
|
||
let tol = (r.width() + r.height()).max(1e-6) / 2000.0;
|
||
let mut poly = flatten_subpath(sp, tol);
|
||
if poly.len() > 1
|
||
&& let (Some(a), Some(b)) = (poly.first(), poly.last())
|
||
&& a.distance(*b) < 1e-9
|
||
{
|
||
poly.pop();
|
||
}
|
||
if poly.len() < 3 {
|
||
return Some(Self::rect(r));
|
||
}
|
||
// Orient clockwise in y-down (TL → TR → BR → BL).
|
||
let area: f64 = (0..poly.len())
|
||
.map(|i| {
|
||
let (p, q) = (poly[i], poly[(i + 1) % poly.len()]);
|
||
p.x * q.y - q.x * p.y
|
||
})
|
||
.sum();
|
||
if area < 0.0 {
|
||
poly.reverse();
|
||
}
|
||
let nearest = |c: Point| (0..poly.len()).min_by(|i, j| poly[*i].distance_squared(c).total_cmp(&poly[*j].distance_squared(c))).unwrap_or(0);
|
||
let tl = nearest(Point::new(r.x0, r.y0));
|
||
let tr = nearest(Point::new(r.x1, r.y0));
|
||
let br = nearest(Point::new(r.x1, r.y1));
|
||
let bl = nearest(Point::new(r.x0, r.y1));
|
||
let n = poly.len();
|
||
let arc = |i: usize, j: usize| -> Vec<Point> {
|
||
let mut v = vec![poly[i]];
|
||
let mut k = i;
|
||
while k != j {
|
||
k = (k + 1) % n;
|
||
v.push(poly[k]);
|
||
}
|
||
v
|
||
};
|
||
let top = resample(&arc(tl, tr), SIDE);
|
||
let right = resample(&arc(tr, br), SIDE);
|
||
let mut bottom = resample(&arc(br, bl), SIDE);
|
||
bottom.reverse();
|
||
let mut left = resample(&arc(bl, tl), SIDE);
|
||
left.reverse();
|
||
Some(Self { top, right, bottom, left })
|
||
}
|
||
|
||
/// The point at `u` along a side; past its ends the end segments go on straight (art an
|
||
/// envelope bends can reach past the content's box: outlined strokes).
|
||
fn sample(side: &[Point], u: f64) -> Point {
|
||
let s = u * (side.len() - 1) as f64;
|
||
let i = (s.floor().max(0.0) as usize).min(side.len() - 2);
|
||
side[i].lerp(side[i + 1], s - i as f64)
|
||
}
|
||
|
||
/// The surface point at (u, v) ∈ [0,1]².
|
||
pub fn eval(&self, u: f64, v: f64) -> Point {
|
||
let (t, b, l, r) = (Self::sample(&self.top, u), Self::sample(&self.bottom, u), Self::sample(&self.left, v), Self::sample(&self.right, v));
|
||
let (p00, p10, p01, p11) = (self.top[0], self.top[SIDE - 1], self.bottom[0], self.bottom[SIDE - 1]);
|
||
let c = (1.0 - v) * t.to_vec2() + v * b.to_vec2() + (1.0 - u) * l.to_vec2() + u * r.to_vec2()
|
||
- ((1.0 - u) * (1.0 - v) * p00.to_vec2() + u * (1.0 - v) * p10.to_vec2() + (1.0 - u) * v * p01.to_vec2() + u * v * p11.to_vec2());
|
||
c.to_point()
|
||
}
|
||
|
||
/// The four corners TL, TR, BR, BL.
|
||
pub fn corners(&self) -> [Point; 4] {
|
||
[self.top[0], self.top[SIDE - 1], self.bottom[SIDE - 1], self.bottom[0]]
|
||
}
|
||
}
|
||
|
||
// =====================================================================================
|
||
// Gradient meshes
|
||
// =====================================================================================
|
||
|
||
/// `0, 1/n, …, 1` for `n` (clamped to 1..=200) even steps.
|
||
fn even_steps(n: u32) -> Vec<f64> {
|
||
let n = n.clamp(1, 200);
|
||
(0..=n).map(|i| i as f64 / n as f64).collect()
|
||
}
|
||
|
||
impl GradientMesh {
|
||
pub fn idx(&self, r: usize, c: usize) -> usize {
|
||
r * (self.cols as usize + 1) + c
|
||
}
|
||
pub fn is_valid(&self) -> bool {
|
||
self.rows >= 1 && self.cols >= 1 && self.points.len() == (self.rows as usize + 1) * (self.cols as usize + 1)
|
||
}
|
||
|
||
/// A mesh over surface `s` (u, v ∈ [0,1]) with handles from its partial derivatives.
|
||
pub fn from_surface(rows: u32, cols: u32, s: &dyn Fn(f64, f64) -> Point, color: &dyn Fn(f64, f64) -> Color) -> Self {
|
||
let (us, vs) = (even_steps(cols), even_steps(rows));
|
||
Self::from_grid(&us, &vs, s, &|r, c, _| (color(us[c], vs[r]), 1.0))
|
||
}
|
||
|
||
/// A mesh over surface `s` (u, v ∈ [0,1]) whose column lines sit at `us` and row lines at `vs`
|
||
/// (ascending, at least two each; equal neighbours make a patch of no width, a sharp colour
|
||
/// change), with handles from its partial derivatives. `color(row, col, point)` gives each
|
||
/// point its colour and opacity.
|
||
pub fn from_grid(us: &[f64], vs: &[f64], s: &dyn Fn(f64, f64) -> Point, color: &dyn Fn(usize, usize, Point) -> (Color, f32)) -> Self {
|
||
let (rows, cols) = (vs.len().saturating_sub(1), us.len().saturating_sub(1));
|
||
let eps = 1e-3;
|
||
let mut points = Vec::with_capacity(us.len() * vs.len());
|
||
for (r, &v) in vs.iter().enumerate() {
|
||
for (c, &u) in us.iter().enumerate() {
|
||
let p = s(u, v);
|
||
let d_u = (s((u + eps).min(1.0), v) - s((u - eps).max(0.0), v)) / ((u + eps).min(1.0) - (u - eps).max(0.0));
|
||
let d_v = (s(u, (v + eps).min(1.0)) - s(u, (v - eps).max(0.0))) / ((v + eps).min(1.0) - (v - eps).max(0.0));
|
||
// A third of the way to the neighbouring line along the tangent; outward handles on
|
||
// the border are unused, so they stay at the point.
|
||
let h = |d: Vec2, from: f64, to: Option<&f64>| to.map_or(Vec2::ZERO, |to| d * ((to - from) / 3.0));
|
||
let handles = [
|
||
h(d_u, u, us.get(c + 1)),
|
||
h(d_u, u, c.checked_sub(1).map(|i| &us[i])),
|
||
h(d_v, v, vs.get(r + 1)),
|
||
h(d_v, v, r.checked_sub(1).map(|i| &vs[i])),
|
||
];
|
||
let (color, opacity) = color(r, c, p);
|
||
points.push(MeshPoint { p, color, opacity, handles });
|
||
}
|
||
}
|
||
Self { rows: rows as u32, cols: cols as u32, points }
|
||
}
|
||
|
||
/// Create Gradient Mesh for a path: the outline split at its corners, coloured per `appearance`.
|
||
pub fn for_path(path: &PathData, rows: u32, cols: u32, base: Color, appearance: MeshAppearance, highlight: f64) -> Option<Self> {
|
||
let mut m = Self::for_path_with(path, rows, cols, &|_| (base, 1.0))?;
|
||
m.highlight(appearance, highlight);
|
||
Some(m)
|
||
}
|
||
|
||
/// Create Gradient Mesh for a path: the outline split at its corners, each point taking the
|
||
/// colour and opacity `color_at` gives at its position (a gradient fill's, say).
|
||
pub fn for_path_with(path: &PathData, rows: u32, cols: u32, color_at: &dyn Fn(Point) -> (Color, f32)) -> Option<Self> {
|
||
let coons = Coons::from_path(path)?;
|
||
Some(Self::from_grid(&even_steps(cols), &even_steps(rows), &|u, v| coons.eval(u, v), &|_, _, p| color_at(p)))
|
||
}
|
||
|
||
/// Create Gradient Mesh → Appearance: lighten the points towards white, to the centre or to
|
||
/// the edges, by at most `highlight` %.
|
||
pub fn highlight(&mut self, appearance: MeshAppearance, highlight: f64) {
|
||
let h = (highlight / 100.0).clamp(0.0, 1.0) as f32;
|
||
let (rows, cols) = (self.rows as usize, self.cols as usize);
|
||
for r in 0..=rows {
|
||
for c in 0..=cols {
|
||
let (u, v) = (c as f64 / cols as f64, r as f64 / rows as f64);
|
||
let d = ((u - 0.5).abs().max((v - 0.5).abs()) * 2.0) as f32; // 0 centre … 1 edge
|
||
let w = match appearance {
|
||
MeshAppearance::Flat => 0.0,
|
||
MeshAppearance::ToCenter => (1.0 - d) * h,
|
||
MeshAppearance::ToEdge => d * h,
|
||
};
|
||
if w > 0.0 {
|
||
let i = self.idx(r, c);
|
||
self.points[i].color = lerp_color(&self.points[i].color, &Color::WHITE, w);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Horizontal edge from (r, c) to (r, c+1).
|
||
pub fn edge_u(&self, r: usize, c: usize) -> CubicBez {
|
||
let (a, b) = (&self.points[self.idx(r, c)], &self.points[self.idx(r, c + 1)]);
|
||
CubicBez::new(a.p, a.p + a.handles[H_RIGHT], b.p + b.handles[H_LEFT], b.p)
|
||
}
|
||
/// Vertical edge from (r, c) to (r+1, c).
|
||
pub fn edge_v(&self, r: usize, c: usize) -> CubicBez {
|
||
let (a, b) = (&self.points[self.idx(r, c)], &self.points[self.idx(r + 1, c)]);
|
||
CubicBez::new(a.p, a.p + a.handles[H_DOWN], b.p + b.handles[H_UP], b.p)
|
||
}
|
||
|
||
/// Coons patch point of patch (r, c) at local (u, v).
|
||
pub fn eval(&self, r: usize, c: usize, u: f64, v: f64) -> Point {
|
||
let (t, b) = (self.edge_u(r, c).eval(u), self.edge_u(r + 1, c).eval(u));
|
||
let (l, rr) = (self.edge_v(r, c).eval(v), self.edge_v(r, c + 1).eval(v));
|
||
let p00 = self.points[self.idx(r, c)].p.to_vec2();
|
||
let p10 = self.points[self.idx(r, c + 1)].p.to_vec2();
|
||
let p01 = self.points[self.idx(r + 1, c)].p.to_vec2();
|
||
let p11 = self.points[self.idx(r + 1, c + 1)].p.to_vec2();
|
||
((1.0 - v) * t.to_vec2() + v * b.to_vec2() + (1.0 - u) * l.to_vec2() + u * rr.to_vec2()
|
||
- ((1.0 - u) * (1.0 - v) * p00 + u * (1.0 - v) * p10 + (1.0 - u) * v * p01 + u * v * p11))
|
||
.to_point()
|
||
}
|
||
|
||
/// Bilinear colour and opacity of patch (r, c) at local (u, v).
|
||
pub fn color_at(&self, r: usize, c: usize, u: f64, v: f64) -> (Color, f32) {
|
||
let q =
|
||
[&self.points[self.idx(r, c)], &self.points[self.idx(r, c + 1)], &self.points[self.idx(r + 1, c)], &self.points[self.idx(r + 1, c + 1)]];
|
||
let w = [(1.0 - u) * (1.0 - v), u * (1.0 - v), (1.0 - u) * v, u * v];
|
||
let mut rgb = [0.0f32; 3];
|
||
let mut op = 0.0f32;
|
||
for k in 0..4 {
|
||
let c = q[k].color.to_rgb();
|
||
for (ch, x) in rgb.iter_mut().zip(c) {
|
||
*ch += x * w[k] as f32;
|
||
}
|
||
op += q[k].opacity * w[k] as f32;
|
||
}
|
||
(Color::rgb(rgb[0], rgb[1], rgb[2]), op)
|
||
}
|
||
|
||
/// Tessellate into `n`×`n` quads per patch, each coloured at its centre.
|
||
pub fn quads(&self, n: usize) -> Vec<MeshQuad> {
|
||
if !self.is_valid() {
|
||
return vec![];
|
||
}
|
||
let n = n.clamp(1, 64);
|
||
let mut out = Vec::with_capacity(self.rows as usize * self.cols as usize * n * n);
|
||
let mut grid = vec![Point::ZERO; (n + 1) * (n + 1)];
|
||
for r in 0..self.rows as usize {
|
||
for c in 0..self.cols as usize {
|
||
for j in 0..=n {
|
||
for i in 0..=n {
|
||
grid[j * (n + 1) + i] = self.eval(r, c, i as f64 / n as f64, j as f64 / n as f64);
|
||
}
|
||
}
|
||
for j in 0..n {
|
||
for i in 0..n {
|
||
let (color, opacity) = self.color_at(r, c, (i as f64 + 0.5) / n as f64, (j as f64 + 0.5) / n as f64);
|
||
let g = |a: usize, b: usize| grid[b * (n + 1) + a];
|
||
out.push(MeshQuad { pts: [g(i, j), g(i + 1, j), g(i + 1, j + 1), g(i, j + 1)], color, opacity });
|
||
}
|
||
}
|
||
}
|
||
}
|
||
out
|
||
}
|
||
|
||
/// The mesh's outer boundary as a closed path.
|
||
pub fn outline(&self) -> PathData {
|
||
if !self.is_valid() {
|
||
return PathData::default();
|
||
}
|
||
let (rows, cols) = (self.rows as usize, self.cols as usize);
|
||
let mut segs: Vec<CubicBez> = vec![];
|
||
for c in 0..cols {
|
||
segs.push(self.edge_u(0, c));
|
||
}
|
||
for r in 0..rows {
|
||
segs.push(self.edge_v(r, cols));
|
||
}
|
||
for c in (0..cols).rev() {
|
||
let e = self.edge_u(rows, c);
|
||
segs.push(CubicBez::new(e.p3, e.p2, e.p1, e.p0));
|
||
}
|
||
for r in (0..rows).rev() {
|
||
let e = self.edge_v(r, 0);
|
||
segs.push(CubicBez::new(e.p3, e.p2, e.p1, e.p0));
|
||
}
|
||
let mut anchors: Vec<Anchor> = Vec::with_capacity(segs.len());
|
||
for (i, s) in segs.iter().enumerate() {
|
||
let prev = &segs[(i + segs.len() - 1) % segs.len()];
|
||
anchors.push(Anchor::with_handles(s.p0, prev.p2, s.p1));
|
||
}
|
||
PathData::single(SubPath::new(anchors, true))
|
||
}
|
||
|
||
/// Mesh lines (all row and column edges) as open paths, for outline view and editing overlays.
|
||
pub fn lines(&self) -> PathData {
|
||
if !self.is_valid() {
|
||
return PathData::default();
|
||
}
|
||
let (rows, cols) = (self.rows as usize, self.cols as usize);
|
||
let mut subs = vec![];
|
||
let cub = |e: CubicBez| SubPath::new(vec![Anchor::with_handles(e.p0, e.p0, e.p1), Anchor::with_handles(e.p3, e.p2, e.p3)], false);
|
||
for r in 0..=rows {
|
||
for c in 0..cols {
|
||
subs.push(cub(self.edge_u(r, c)));
|
||
}
|
||
}
|
||
for c in 0..=cols {
|
||
for r in 0..rows {
|
||
subs.push(cub(self.edge_v(r, c)));
|
||
}
|
||
}
|
||
PathData::new(subs)
|
||
}
|
||
|
||
/// Control bounds (points and handles).
|
||
pub fn bounds(&self) -> Option<Rect> {
|
||
let mut it = self.points.iter().flat_map(|p| std::iter::once(p.p).chain(p.handles.iter().map(move |h| p.p + *h)));
|
||
let first = it.next()?;
|
||
Some(it.fold(Rect::from_points(first, first), |r, q| r.union_pt(q)))
|
||
}
|
||
|
||
pub fn transform(&mut self, a: Affine) {
|
||
let lin = Affine::new({
|
||
let c = a.as_coeffs();
|
||
[c[0], c[1], c[2], c[3], 0.0, 0.0]
|
||
});
|
||
for p in &mut self.points {
|
||
p.p = a * p.p;
|
||
for h in &mut p.handles {
|
||
*h = (lin * h.to_point()).to_vec2();
|
||
}
|
||
}
|
||
}
|
||
|
||
/// Map points (and handle ends) through a non-linear function.
|
||
pub fn map(&mut self, f: &dyn Fn(Point) -> Point) {
|
||
for p in &mut self.points {
|
||
let q = f(p.p);
|
||
for h in &mut p.handles {
|
||
*h = f(p.p + *h) - q;
|
||
}
|
||
p.p = q;
|
||
}
|
||
}
|
||
|
||
/// Which patch and local (u, v) contains `p` (sampled search; `None` outside the mesh).
|
||
pub fn locate(&self, p: Point) -> Option<(usize, usize, f64, f64)> {
|
||
if !self.is_valid() {
|
||
return None;
|
||
}
|
||
let bp = self.outline().to_bezpath();
|
||
if bp.winding(p) == 0 {
|
||
return None;
|
||
}
|
||
const N: usize = 16;
|
||
let mut best = (f64::INFINITY, 0, 0, 0.0, 0.0);
|
||
for r in 0..self.rows as usize {
|
||
for c in 0..self.cols as usize {
|
||
for j in 0..=N {
|
||
for i in 0..=N {
|
||
let (u, v) = (i as f64 / N as f64, j as f64 / N as f64);
|
||
let d = self.eval(r, c, u, v).distance_squared(p);
|
||
if d < best.0 {
|
||
best = (d, r, c, u, v);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
// Refine with a few Newton-free local searches.
|
||
let (_, r, c, mut u, mut v) = best;
|
||
let mut step = 0.5 / N as f64;
|
||
for _ in 0..12 {
|
||
let mut improved = false;
|
||
for (du, dv) in [(step, 0.0), (-step, 0.0), (0.0, step), (0.0, -step)] {
|
||
let (nu, nv) = ((u + du).clamp(0.0, 1.0), (v + dv).clamp(0.0, 1.0));
|
||
if self.eval(r, c, nu, nv).distance_squared(p) < self.eval(r, c, u, v).distance_squared(p) {
|
||
u = nu;
|
||
v = nv;
|
||
improved = true;
|
||
}
|
||
}
|
||
if !improved {
|
||
step /= 2.0;
|
||
}
|
||
}
|
||
Some((r, c, u, v))
|
||
}
|
||
|
||
/// Index of the mesh point within `tol` of `p`.
|
||
pub fn point_near(&self, p: Point, tol: f64) -> Option<usize> {
|
||
self.points
|
||
.iter()
|
||
.enumerate()
|
||
.filter(|(_, q)| q.p.distance(p) <= tol)
|
||
.min_by(|a, b| a.1.p.distance(p).total_cmp(&b.1.p.distance(p)))
|
||
.map(|(i, _)| i)
|
||
}
|
||
|
||
fn surface_du(&self, r: usize, c: usize, u: f64, v: f64) -> Vec2 {
|
||
let e = 1e-3;
|
||
let (a, b) = ((u - e).max(0.0), (u + e).min(1.0));
|
||
(self.eval(r, c, b, v) - self.eval(r, c, a, v)) / (b - a)
|
||
}
|
||
fn surface_dv(&self, r: usize, c: usize, u: f64, v: f64) -> Vec2 {
|
||
let e = 1e-3;
|
||
let (a, b) = ((v - e).max(0.0), (v + e).min(1.0));
|
||
(self.eval(r, c, u, b) - self.eval(r, c, u, a)) / (b - a)
|
||
}
|
||
|
||
/// Insert a mesh row through patch row `r` at local `v`.
|
||
pub fn insert_row(&mut self, r: usize, v: f64) {
|
||
let cols = self.cols as usize;
|
||
let v = v.clamp(0.01, 0.99);
|
||
let mut row = Vec::with_capacity(cols + 1);
|
||
// Split the vertical edges.
|
||
let mut ups = vec![];
|
||
for c in 0..=cols {
|
||
let e = self.edge_v(r, c);
|
||
let (l, rr) = (e.subsegment(0.0..v), e.subsegment(v..1.0));
|
||
ups.push((l.p1 - l.p0, rr.p2 - rr.p3));
|
||
let pc = c.min(cols - 1);
|
||
let u = if c == cols { 1.0 } else { 0.0 };
|
||
let (color, opacity) = self.color_at(r, pc, u, v);
|
||
// Horizontal handles: isocurve derivatives on either side.
|
||
let right = if c < cols { self.surface_du(r, c, 0.0, v) / (3.0) } else { Vec2::ZERO };
|
||
let left = if c > 0 { -self.surface_du(r, c - 1, 1.0, v) / 3.0 } else { Vec2::ZERO };
|
||
row.push(MeshPoint { p: l.p3, color, opacity, handles: [right, left, rr.p1 - rr.p0, l.p2 - l.p3] });
|
||
}
|
||
for (c, (down, up)) in ups.into_iter().enumerate() {
|
||
let i0 = self.idx(r, c);
|
||
let i1 = self.idx(r + 1, c);
|
||
self.points[i0].handles[H_DOWN] = down;
|
||
self.points[i1].handles[H_UP] = up;
|
||
}
|
||
let at = self.idx(r + 1, 0);
|
||
self.points.splice(at..at, row);
|
||
self.rows += 1;
|
||
}
|
||
|
||
/// Insert a mesh column through patch column `c` at local `u`.
|
||
pub fn insert_col(&mut self, c: usize, u: f64) {
|
||
let rows = self.rows as usize;
|
||
let u = u.clamp(0.01, 0.99);
|
||
let mut col = Vec::with_capacity(rows + 1);
|
||
for r in 0..=rows {
|
||
let e = self.edge_u(r, c);
|
||
let (l, rr) = (e.subsegment(0.0..u), e.subsegment(u..1.0));
|
||
let pr = r.min(rows - 1);
|
||
let v = if r == rows { 1.0 } else { 0.0 };
|
||
let (color, opacity) = self.color_at(pr, c, u, v);
|
||
let down = if r < rows { self.surface_dv(r, c, u, 0.0) / 3.0 } else { Vec2::ZERO };
|
||
let up = if r > 0 { -self.surface_dv(r - 1, c, u, 1.0) / 3.0 } else { Vec2::ZERO };
|
||
col.push((MeshPoint { p: l.p3, color, opacity, handles: [rr.p1 - rr.p0, l.p2 - l.p3, down, up] }, l.p1 - l.p0, rr.p2 - rr.p3));
|
||
}
|
||
let cols = self.cols as usize;
|
||
let mut pts = Vec::with_capacity((rows + 1) * (cols + 2));
|
||
for (r, (mp, right, left)) in col.into_iter().enumerate() {
|
||
for cc in 0..=cols {
|
||
let mut q = self.points[r * (cols + 1) + cc].clone();
|
||
if cc == c {
|
||
q.handles[H_RIGHT] = right;
|
||
}
|
||
if cc == c + 1 {
|
||
q.handles[H_LEFT] = left;
|
||
}
|
||
pts.push(q);
|
||
if cc == c {
|
||
pts.push(mp.clone());
|
||
}
|
||
}
|
||
}
|
||
self.points = pts;
|
||
self.cols += 1;
|
||
}
|
||
|
||
/// Mesh tool click: add a row and a column through `p` (inside the mesh). Returns the new point index.
|
||
pub fn add_lines_at(&mut self, p: Point) -> Option<usize> {
|
||
let (r, c, u, v) = self.locate(p)?;
|
||
let mut rr = r;
|
||
let mut cc = c;
|
||
let row_new = v > 0.02 && v < 0.98;
|
||
let col_new = u > 0.02 && u < 0.98;
|
||
if row_new {
|
||
self.insert_row(r, v);
|
||
rr = r + 1;
|
||
} else if v >= 0.98 {
|
||
rr = r + 1;
|
||
}
|
||
if col_new {
|
||
self.insert_col(c, u);
|
||
cc = c + 1;
|
||
} else if u >= 0.98 {
|
||
cc = c + 1;
|
||
}
|
||
Some(self.idx(rr, cc))
|
||
}
|
||
|
||
/// Mesh tool Alt-click: delete the mesh lines through point `index` (interior lines only).
|
||
pub fn remove_point_lines(&mut self, index: usize) -> bool {
|
||
if index >= self.points.len() {
|
||
return false;
|
||
}
|
||
let w = self.cols as usize + 1;
|
||
let (r, c) = (index / w, index % w);
|
||
let mut changed = false;
|
||
if r > 0 && r < self.rows as usize {
|
||
// Merge the edges above and below: keep the outer handles.
|
||
for cc in 0..w {
|
||
let above = self.idx(r - 1, cc);
|
||
let below = self.idx(r + 1, cc);
|
||
let mid = self.idx(r, cc);
|
||
let (pa, pm, pb) = (self.points[above].p, self.points[mid].p, self.points[below].p);
|
||
let _ = pm;
|
||
self.points[above].handles[H_DOWN] = (pb - pa) / 3.0;
|
||
self.points[below].handles[H_UP] = (pa - pb) / 3.0;
|
||
}
|
||
self.points.drain(r * w..(r + 1) * w);
|
||
self.rows -= 1;
|
||
changed = true;
|
||
}
|
||
let w = self.cols as usize + 1;
|
||
if c > 0 && c < self.cols as usize {
|
||
let rows = self.rows as usize;
|
||
for rr in 0..=rows {
|
||
let (l, rt) = (rr * w + c - 1, rr * w + c + 1);
|
||
let (pl, pr) = (self.points[l].p, self.points[rt].p);
|
||
self.points[l].handles[H_RIGHT] = (pr - pl) / 3.0;
|
||
self.points[rt].handles[H_LEFT] = (pl - pr) / 3.0;
|
||
}
|
||
let mut k = 0;
|
||
self.points.retain(|_| {
|
||
let keep = k % w != c;
|
||
k += 1;
|
||
keep
|
||
});
|
||
self.cols -= 1;
|
||
changed = true;
|
||
}
|
||
changed
|
||
}
|
||
}
|
||
|
||
// =====================================================================================
|
||
// Envelopes
|
||
// =====================================================================================
|
||
|
||
/// Union of the geometric bounds of `nodes`.
|
||
pub fn nodes_bounds(nodes: &[Arc<Node>]) -> Option<Rect> {
|
||
nodes.iter().fold(None, |acc, c| vectorcraft_geom::union_opt(acc, c.geometric_bounds()))
|
||
}
|
||
|
||
/// A `(rows+1)×(cols+1)` grid over `r` (row-major).
|
||
pub fn grid_points(r: Rect, rows: u32, cols: u32) -> Vec<Point> {
|
||
let mut v = Vec::with_capacity(((rows + 1) * (cols + 1)) as usize);
|
||
for i in 0..=rows {
|
||
for j in 0..=cols {
|
||
v.push(Point::new(r.x0 + r.width() * j as f64 / cols.max(1) as f64, r.y0 + r.height() * i as f64 / rows.max(1) as f64));
|
||
}
|
||
}
|
||
v
|
||
}
|
||
|
||
fn catmull(p0: Vec2, p1: Vec2, p2: Vec2, p3: Vec2, t: f64) -> Vec2 {
|
||
let t2 = t * t;
|
||
let t3 = t2 * t;
|
||
0.5 * (2.0 * p1 + (p2 - p0) * t + (2.0 * p0 - 5.0 * p1 + 4.0 * p2 - p3) * t2 + (3.0 * p1 - p0 - 3.0 * p2 + p3) * t3)
|
||
}
|
||
|
||
/// Point map from the unit square onto a point grid (tensor-product Catmull-Rom; linear
|
||
/// extrapolation at the borders so an undistorted grid is the identity, also past the square).
|
||
fn grid_eval(rows: usize, cols: usize, pts: &[Point], u: f64, v: f64) -> Point {
|
||
let at = |r: i64, c: i64| -> Vec2 {
|
||
let rr = r.clamp(0, rows as i64);
|
||
let cc = c.clamp(0, cols as i64);
|
||
let base = pts[rr as usize * (cols + 1) + cc as usize].to_vec2();
|
||
// Linear extrapolation outside the grid.
|
||
let er = r - rr;
|
||
let ec = c - cc;
|
||
let mut p = base;
|
||
if er != 0 && rows >= 1 {
|
||
let inner = (rr - er.signum()).clamp(0, rows as i64);
|
||
p += (base - pts[inner as usize * (cols + 1) + cc as usize].to_vec2()) * er.abs() as f64;
|
||
}
|
||
if ec != 0 && cols >= 1 {
|
||
let inner = (cc - ec.signum()).clamp(0, cols as i64);
|
||
p += (base - pts[rr as usize * (cols + 1) + inner as usize].to_vec2()) * ec.abs() as f64;
|
||
}
|
||
p
|
||
};
|
||
// Past the grid's edges the outer patches go on (art can reach past the content's box).
|
||
let (su, sv) = (u * cols as f64, v * rows as f64);
|
||
let (ci, ri) = ((su.floor() as i64).clamp(0, cols as i64 - 1), (sv.floor() as i64).clamp(0, rows as i64 - 1));
|
||
let (fu, fv) = (su - ci as f64, sv - ri as f64);
|
||
let mut rowsv = [Vec2::ZERO; 4];
|
||
for (k, rv) in rowsv.iter_mut().enumerate() {
|
||
let r = ri - 1 + k as i64;
|
||
*rv = catmull(at(r, ci - 1), at(r, ci), at(r, ci + 1), at(r, ci + 2), fu);
|
||
}
|
||
catmull(rowsv[0], rowsv[1], rowsv[2], rowsv[3], fv).to_point()
|
||
}
|
||
|
||
/// The surface (u, v ∈ [0,1]) an envelope of `kind` maps content onto, for content whose bounds in
|
||
/// the envelope's own `frame` (its axes → the document) are `src`: a warp bends along the frame's
|
||
/// axes; a mesh's points and a top object's path are in the document already.
|
||
fn surface_of<'a>(kind: &'a EnvelopeKind, src: Rect, frame: Affine) -> Box<dyn Fn(f64, f64) -> Point + 'a> {
|
||
let flat = move |u: f64, v: f64| frame * Point::new(src.x0 + u * src.width(), src.y0 + v * src.height());
|
||
match kind {
|
||
EnvelopeKind::Warp { style, bend, h: dh, v: dv, horizontal } => {
|
||
let st = WarpStyle::from_id(style).unwrap_or(WarpStyle::Arc);
|
||
let b = bend.clamp(-100.0, 100.0) / 100.0;
|
||
let (dh, dv) = (dh.clamp(-100.0, 100.0) / 100.0, dv.clamp(-100.0, 100.0) / 100.0);
|
||
let c = src.center();
|
||
let (hw, hh) = (src.width() / 2.0, src.height() / 2.0);
|
||
let horizontal = *horizontal;
|
||
Box::new(move |u: f64, v: f64| {
|
||
let (x, y) = (2.0 * u - 1.0, 2.0 * v - 1.0);
|
||
let (x2, y2) = if horizontal {
|
||
warp_point(st, b, dh, dv, x, y)
|
||
} else {
|
||
let (a, b2) = warp_point(st, b, dh, dv, y, x);
|
||
(b2, a)
|
||
};
|
||
frame * Point::new(c.x + x2 * hw, c.y + y2 * hh)
|
||
})
|
||
}
|
||
EnvelopeKind::Mesh { rows, cols, points } => {
|
||
let (rows, cols) = (*rows as usize, *cols as usize);
|
||
if rows == 0 || cols == 0 || points.len() != (rows + 1) * (cols + 1) {
|
||
return Box::new(flat);
|
||
}
|
||
Box::new(move |u: f64, v: f64| grid_eval(rows, cols, points, u, v))
|
||
}
|
||
EnvelopeKind::TopObject { path } => match Coons::from_path(path) {
|
||
Some(co) => Box::new(move |u: f64, v: f64| co.eval(u, v)),
|
||
None => Box::new(flat),
|
||
},
|
||
}
|
||
}
|
||
|
||
/// The envelope's point map for content whose bounding box is `src` (page axes).
|
||
pub fn envelope_mapper<'a>(kind: &'a EnvelopeKind, src: Rect) -> Box<dyn Fn(Point) -> Point + 'a> {
|
||
let s = surface_of(kind, src, Affine::IDENTITY);
|
||
let (w, h) = (src.width().max(1e-9), src.height().max(1e-9));
|
||
Box::new(move |q: Point| s((q.x - src.x0) / w, (q.y - src.y0) / h))
|
||
}
|
||
|
||
/// The frame an envelope keeps after transform `m` (its frame so far composed with the
|
||
/// transform): identity when its axes stay square to the page, unflipped, since evaluating on
|
||
/// the page axes gives the same result then.
|
||
pub fn envelope_frame(m: Affine) -> Affine {
|
||
let [a, b, c, d, _, _] = m.as_coeffs();
|
||
if b.abs() < 1e-12 && c.abs() < 1e-12 && a > 0.0 && d > 0.0 { Affine::IDENTITY } else { m }
|
||
}
|
||
|
||
/// An envelope's point map: content placed in the envelope's own frame maps, by its bounds there,
|
||
/// onto the unit square and from there onto the envelope's surface ([`surface_of`]).
|
||
pub struct EnvelopeMap<'a> {
|
||
src: Rect,
|
||
frame: Affine,
|
||
to_frame: Affine,
|
||
surface: Box<dyn Fn(f64, f64) -> Point + 'a>,
|
||
}
|
||
|
||
impl<'a> EnvelopeMap<'a> {
|
||
/// The map of an envelope of `kind` around `content` with `frame`. `None` when the content
|
||
/// has no bounds.
|
||
pub fn new(content: &[Arc<Node>], kind: &'a EnvelopeKind, frame: Affine) -> Option<Self> {
|
||
let frame = if frame.is_finite() && frame.determinant().abs() > 1e-12 { frame } else { Affine::IDENTITY };
|
||
let to_frame = frame.inverse();
|
||
let src = if frame == Affine::IDENTITY {
|
||
nodes_bounds(content)?
|
||
} else {
|
||
content.iter().try_fold(None, |acc, c| {
|
||
let mut m = (**c).clone();
|
||
m.transform(to_frame, false);
|
||
Some(vectorcraft_geom::union_opt(acc, m.geometric_bounds()))
|
||
})??
|
||
};
|
||
Some(Self { src, frame, to_frame, surface: surface_of(kind, src, frame) })
|
||
}
|
||
|
||
/// The map of envelope node `n` (`None` for other nodes).
|
||
pub fn of(n: &'a Node) -> Option<Self> {
|
||
match &n.kind {
|
||
NodeKind::Envelope { content, kind, frame, .. } => Self::new(content, kind, *frame),
|
||
_ => None,
|
||
}
|
||
}
|
||
|
||
/// The content's bounds in the envelope's frame.
|
||
pub fn src(&self) -> Rect {
|
||
self.src
|
||
}
|
||
|
||
/// The surface point at (u, v) ∈ [0,1]².
|
||
pub fn at(&self, u: f64, v: f64) -> Point {
|
||
(self.surface)(u, v)
|
||
}
|
||
|
||
/// Where the envelope puts document point `p`.
|
||
pub fn map(&self, p: Point) -> Point {
|
||
let q = self.to_frame * p;
|
||
let (w, h) = (self.src.width().max(1e-9), self.src.height().max(1e-9));
|
||
self.at((q.x - self.src.x0) / w, (q.y - self.src.y0) / h)
|
||
}
|
||
|
||
/// A flat `(rows+1)×(cols+1)` grid over the content, in the envelope's frame (row-major).
|
||
pub fn grid(&self, rows: u32, cols: u32) -> Vec<Point> {
|
||
grid_points(self.src, rows, cols).into_iter().map(|p| self.frame * p).collect()
|
||
}
|
||
|
||
/// The surface sampled on a `rows`×`cols` grid as a mesh whose handles follow it and whose
|
||
/// points are `color`: Release gives it back as the envelope's shape, Reset with Mesh starts
|
||
/// from it.
|
||
pub fn surface_mesh(&self, rows: u32, cols: u32, color: Color) -> GradientMesh {
|
||
GradientMesh::from_surface(rows, cols, &|u, v| self.at(u, v), &|_, _| color)
|
||
}
|
||
|
||
/// The surface's bounds (sampled; a mesh's points and a top object's path bound it exactly).
|
||
fn bounds(&self) -> Option<Rect> {
|
||
const N: usize = 16;
|
||
let mut r: Option<Rect> = None;
|
||
for j in 0..=N {
|
||
for i in 0..=N {
|
||
let q = self.at(i as f64 / N as f64, j as f64 / N as f64);
|
||
r = Some(r.map_or(Rect::from_points(q, q), |r| r.union_pt(q)));
|
||
}
|
||
}
|
||
r
|
||
}
|
||
}
|
||
|
||
/// Optional hook that converts nodes the pure evaluation can't map (text) to outlines.
|
||
pub type Outliner<'a> = Option<&'a dyn Fn(&Node) -> Option<Node>>;
|
||
|
||
/// Distort Pattern Fills: the tiles pattern swatch `name` painted with placement `xf` lays over
|
||
/// `region` (see [`crate::PatternDef::instances_in`]); `None` without such a swatch.
|
||
pub type PatternTiles<'a> = &'a dyn Fn(&str, Affine, Rect) -> Option<Vec<Node>>;
|
||
|
||
/// What live evaluation asks of the crates above this one (`vectorcraft-effects` supplies them).
|
||
#[derive(Clone, Copy, Default)]
|
||
pub struct Hooks<'a> {
|
||
/// Type as its glyph outlines, a symbol instance as its art (see [`Outliner`]).
|
||
pub outline: Outliner<'a>,
|
||
/// Distort Appearance: a path's strokes and geometry effects baked into filled art (`None`
|
||
/// when it has none to bake).
|
||
pub appearance: Outliner<'a>,
|
||
/// Distort Pattern Fills: the tiles a pattern fill lays (see [`PatternTiles`]).
|
||
pub pattern: Option<PatternTiles<'a>>,
|
||
}
|
||
|
||
impl<'a> From<Outliner<'a>> for Hooks<'a> {
|
||
fn from(outline: Outliner<'a>) -> Self {
|
||
Self { outline, ..Default::default() }
|
||
}
|
||
}
|
||
|
||
/// The affine map that best matches `f` near `p` (finite differences with step `eps`).
|
||
pub fn affine_near(f: &dyn Fn(Point) -> Point, p: Point, eps: f64) -> Affine {
|
||
let o = f(p);
|
||
let ex = (f(p + Vec2::new(eps, 0.0)) - f(p - Vec2::new(eps, 0.0))) / (2.0 * eps);
|
||
let ey = (f(p + Vec2::new(0.0, eps)) - f(p - Vec2::new(0.0, eps))) / (2.0 * eps);
|
||
let lin = Affine::new([ex.x, ex.y, ey.x, ey.y, 0.0, 0.0]);
|
||
Affine::translate(o.to_vec2()) * lin * Affine::translate(-p.to_vec2())
|
||
}
|
||
|
||
/// How deep hooks may nest art inside art (symbols in symbols, envelopes in envelopes) before
|
||
/// the rest is left as it is: a file can make a symbol contain itself.
|
||
const MAX_HOOK_DEPTH: u32 = 16;
|
||
|
||
/// How an envelope pushes art through its point map.
|
||
#[derive(Clone, Copy)]
|
||
struct Warper<'a> {
|
||
f: &'a dyn Fn(Point) -> Point,
|
||
/// Longest piece a segment is cut into before mapping.
|
||
piece: f64,
|
||
/// Finite-difference step for the local affine maps gradients follow.
|
||
eps: f64,
|
||
/// Rows and columns of the pieces an image is cut into.
|
||
cells: usize,
|
||
hooks: Hooks<'a>,
|
||
options: EnvelopeOptions,
|
||
/// How many hooks the art being mapped came through.
|
||
depth: u32,
|
||
}
|
||
|
||
impl Warper<'_> {
|
||
/// This warper one hook deeper (`None` past [`MAX_HOOK_DEPTH`]).
|
||
fn deeper(&self) -> Option<Self> {
|
||
(self.depth < MAX_HOOK_DEPTH).then_some(Self { depth: self.depth + 1, ..*self })
|
||
}
|
||
}
|
||
|
||
/// `to` (art standing in for `from`: its outlines, its art) with `from`'s name, transparency,
|
||
/// opacity mask and effects.
|
||
fn carry_look(from: &Node, mut to: Node) -> Node {
|
||
to.name = from.name.clone();
|
||
to.opacity = from.opacity;
|
||
to.blend = from.blend;
|
||
to.isolate = from.isolate;
|
||
to.knockout = from.knockout;
|
||
to.knockout_shape = from.knockout_shape;
|
||
to.mask = from.mask.clone();
|
||
to.appearance.effects = from.appearance.effects.clone();
|
||
to
|
||
}
|
||
|
||
fn map_node(n: &Node, w: &Warper) -> Node {
|
||
let deeper = w.deeper();
|
||
// Distort Appearance: strokes and geometry effects bend with the art.
|
||
if w.options.distort_appearance
|
||
&& let Some(d) = &deeper
|
||
&& let Some(o) = w.hooks.appearance.and_then(|h| h(n))
|
||
{
|
||
return map_node(&o, d);
|
||
}
|
||
// Distort Pattern Fills: the tiles bend with the art (not the patterns inside them).
|
||
if w.options.patterns()
|
||
&& let Some(d) = &deeper
|
||
&& let Some(o) = w.hooks.pattern.and_then(|p| pattern_art(n, p))
|
||
{
|
||
let inner = Warper { options: EnvelopeOptions { distort_pattern_fills: false, ..d.options }, ..*d };
|
||
return map_node(&o, &inner);
|
||
}
|
||
let mut out = n.clone();
|
||
// Distort Linear Gradients: the gradient vectors follow the warp where they sit.
|
||
if w.options.gradients()
|
||
&& let Some(b) = n.geometric_bounds()
|
||
{
|
||
out.appearance.warp_linear_gradients(b, &|p| affine_near(w.f, p, w.eps));
|
||
}
|
||
if let Some(m) = &mut out.mask {
|
||
m.art = Arc::new(map_node(&m.art, w));
|
||
}
|
||
match &mut out.kind {
|
||
NodeKind::Path { path, live, .. } => {
|
||
*path = map_nonlinear(path, w.piece, w.f);
|
||
*live = None;
|
||
}
|
||
NodeKind::Layer { children, .. } | NodeKind::Group { children, .. } | NodeKind::Compound { children, .. } => {
|
||
for c in children.iter_mut() {
|
||
*c = Arc::new(map_node(c, w));
|
||
}
|
||
}
|
||
NodeKind::Mesh(m) => m.map(w.f),
|
||
NodeKind::Blend { .. } | NodeKind::Envelope { .. } | NodeKind::Repeat(_) => {
|
||
if let Some(d) = &deeper {
|
||
return map_node(&expanded_group_hooks(n, w.hooks), d);
|
||
}
|
||
}
|
||
NodeKind::Text(_) | NodeKind::SymbolInstance { .. } => {
|
||
if let Some(d) = &deeper
|
||
&& let Some(o) = w.hooks.outline.and_then(|h| h(n))
|
||
{
|
||
return map_node(&carry_look(n, o), d);
|
||
}
|
||
}
|
||
NodeKind::Image(im) => {
|
||
let im = im.clone();
|
||
return warp_image(&out, &im, w);
|
||
}
|
||
}
|
||
out
|
||
}
|
||
|
||
/// The affine map taking triangle `s` to triangle `d` (`None` when `s` is degenerate).
|
||
fn affine_between(s: [Point; 3], d: [Point; 3]) -> Option<Affine> {
|
||
let basis = |p: [Point; 3]| Affine::new([p[1].x - p[0].x, p[1].y - p[0].y, p[2].x - p[0].x, p[2].y - p[0].y, p[0].x, p[0].y]);
|
||
let bs = basis(s);
|
||
if bs.determinant().abs() < 1e-12 {
|
||
return None;
|
||
}
|
||
let a = basis(d) * bs.inverse();
|
||
a.is_finite().then_some(a)
|
||
}
|
||
|
||
/// Image `n` (`im`) pushed through the warp as a raster mesh warp: its frame cut into
|
||
/// `w.cells`² cells of two triangles, each a clip group showing the image under the affine map
|
||
/// that takes the triangle where the warp takes its corners. Each piece reaches a little past its
|
||
/// edges (at most half a point) so neighbours overlap and no seams show.
|
||
fn warp_image(n: &Node, im: &ImageObject, w: &Warper) -> Node {
|
||
let k = w.cells.max(1);
|
||
let (pw, ph) = (im.width as f64, im.height as f64);
|
||
let at = |i: usize, j: usize| Point::new(pw * i as f64 / k as f64, ph * j as f64 / k as f64);
|
||
let mut pieces = Vec::with_capacity(2 * k * k);
|
||
for j in 0..k {
|
||
for i in 0..k {
|
||
let s = [at(i, j), at(i + 1, j), at(i + 1, j + 1), at(i, j + 1)];
|
||
let d = s.map(|p| (w.f)(im.xf * p));
|
||
for t in [[0, 1, 2], [0, 2, 3]] {
|
||
let (st, dt) = (t.map(|v| s[v]), t.map(|v| d[v]));
|
||
let Some(xf) = affine_between(st, dt) else { continue };
|
||
let c = Point::new((dt[0].x + dt[1].x + dt[2].x) / 3.0, (dt[0].y + dt[1].y + dt[2].y) / 3.0);
|
||
let grow = (dt[0].distance(dt[1]).max(dt[1].distance(dt[2])) * 0.02).min(0.5);
|
||
let tri: Vec<Point> = dt
|
||
.iter()
|
||
.map(|p| {
|
||
let v = *p - c;
|
||
let len = v.hypot();
|
||
if len > 1e-12 { *p + v * (grow / len) } else { *p }
|
||
})
|
||
.collect();
|
||
let mut clip = Node::path(n.id, PathData::single(SubPath::polyline(&tri, true)), Appearance::default());
|
||
if let NodeKind::Path { clipping, .. } = &mut clip.kind {
|
||
*clipping = true;
|
||
}
|
||
let image = Node::new(n.id, NodeKind::Image(ImageObject { xf, ..im.clone() }));
|
||
pieces.push(Arc::new(Node::new(n.id, NodeKind::Group { children: vec![Arc::new(clip), Arc::new(image)], clip: true })));
|
||
}
|
||
}
|
||
}
|
||
let mut g = n.clone();
|
||
g.kind = NodeKind::Group { children: pieces, clip: false };
|
||
g
|
||
}
|
||
|
||
/// Distort Pattern Fills: path or compound path `n` with each visible pattern fill turned into the
|
||
/// tiles it paints in a clip group shaped like `n` (with the fill's opacity and blend mode), its
|
||
/// other fills and strokes on copies of it, in paint order, under `n`'s transparency. `None`
|
||
/// without a pattern fill whose definition `pattern` finds.
|
||
fn pattern_art(n: &Node, tiles: PatternTiles) -> Option<Node> {
|
||
let (path, rule, _) = crate::blend::node_path(n)?;
|
||
let pattern_fill = |i: &AppearanceItem| matches!(i, AppearanceItem::Fill(f) if f.visible && matches!(f.paint, Paint::Pattern { .. }));
|
||
if !n.appearance.items.iter().any(pattern_fill) {
|
||
return None;
|
||
}
|
||
let bounds = path.bounds()?;
|
||
let def = |i: &AppearanceItem| match i {
|
||
AppearanceItem::Fill(f) if f.visible => match &f.paint {
|
||
Paint::Pattern { pattern: name, xf } => tiles(name, *xf, bounds).map(|t| (t, f.opacity, f.blend)),
|
||
_ => None,
|
||
},
|
||
_ => None,
|
||
};
|
||
let plain = |items: Vec<AppearanceItem>| {
|
||
Arc::new(Node {
|
||
appearance: Appearance { items, ..Default::default() },
|
||
opacity: 1.0,
|
||
blend: Default::default(),
|
||
isolate: false,
|
||
knockout: Default::default(),
|
||
knockout_shape: false,
|
||
mask: None,
|
||
name: None,
|
||
..n.clone()
|
||
})
|
||
};
|
||
let mut pieces = vec![];
|
||
let mut rest = vec![];
|
||
for i in &n.appearance.items {
|
||
let Some((tiles, opacity, blend)) = def(i) else {
|
||
rest.push(i.clone());
|
||
continue;
|
||
};
|
||
if !rest.is_empty() {
|
||
pieces.push(plain(std::mem::take(&mut rest)));
|
||
}
|
||
let mut clip = Node::path(n.id, path.clone(), Appearance::default());
|
||
if let NodeKind::Path { clipping, rule: r, .. } = &mut clip.kind {
|
||
(*clipping, *r) = (true, rule);
|
||
}
|
||
let children = std::iter::once(clip).chain(tiles).map(Arc::new).collect();
|
||
let mut g = Node::new(n.id, NodeKind::Group { children, clip: true });
|
||
g.opacity = opacity;
|
||
g.blend = blend;
|
||
pieces.push(Arc::new(g));
|
||
}
|
||
if !rest.is_empty() {
|
||
pieces.push(plain(rest));
|
||
}
|
||
Some(Node {
|
||
kind: NodeKind::Group { children: pieces, clip: false },
|
||
appearance: Appearance { effects: n.appearance.effects.clone(), ..Default::default() },
|
||
..n.clone()
|
||
})
|
||
}
|
||
|
||
/// Evaluate an envelope of `kind` around `content` on the page axes with the options envelopes
|
||
/// had before Envelope Options (see [`expand_live_hooks`] for an envelope node).
|
||
pub fn envelope_expand(content: &[Arc<Node>], kind: &EnvelopeKind, fidelity: f64, outline: Outliner) -> Vec<Node> {
|
||
expand_envelope(content, kind, fidelity, EnvelopeOptions::default(), Affine::IDENTITY, outline.into())
|
||
}
|
||
|
||
/// An envelope's content pushed through its map: Fidelity sets how finely curves are cut (and
|
||
/// into how many pieces images are), the options what bends with the art.
|
||
fn expand_envelope(content: &[Arc<Node>], kind: &EnvelopeKind, fidelity: f64, options: EnvelopeOptions, frame: Affine, hooks: Hooks) -> Vec<Node> {
|
||
let Some(map) = EnvelopeMap::new(content, kind, frame) else { return content.iter().map(|c| (**c).clone()).collect() };
|
||
let src = map.src();
|
||
let fid = if fidelity.is_finite() { fidelity.clamp(0.0, 100.0) / 100.0 } else { 0.5 };
|
||
let f = |p: Point| map.map(p);
|
||
let w = Warper {
|
||
f: &f,
|
||
piece: src.width().hypot(src.height()).max(1e-6) / (8.0 + fid * 56.0),
|
||
eps: (src.width().max(src.height()) * 0.05).max(0.5),
|
||
cells: (4.0 + fid * 12.0).round() as usize,
|
||
hooks,
|
||
options,
|
||
depth: 0,
|
||
};
|
||
content.iter().map(|c| map_node(c, &w)).collect()
|
||
}
|
||
|
||
/// Envelope bounds: a mesh's points, a top object's path, the warp's surface (sampled).
|
||
pub fn envelope_bounds(content: &[Arc<Node>], kind: &EnvelopeKind, frame: Affine) -> Option<Rect> {
|
||
match kind {
|
||
EnvelopeKind::Mesh { points, .. } => {
|
||
let first = *points.first()?;
|
||
Some(points.iter().fold(Rect::from_points(first, first), |r, p| r.union_pt(*p)))
|
||
}
|
||
EnvelopeKind::TopObject { path } => path.bounds(),
|
||
EnvelopeKind::Warp { .. } => EnvelopeMap::new(content, kind, frame)?.bounds(),
|
||
}
|
||
}
|
||
|
||
// =====================================================================================
|
||
// Expansion
|
||
// =====================================================================================
|
||
|
||
/// Is this one of the live kinds?
|
||
pub fn is_live(n: &Node) -> bool {
|
||
matches!(n.kind, NodeKind::Blend { .. } | NodeKind::Envelope { .. } | NodeKind::Mesh(_) | NodeKind::Repeat(_))
|
||
}
|
||
|
||
/// Mesh tessellation as filled quad paths (no stroke), `n`×`n` per patch.
|
||
pub fn mesh_quad_nodes(m: &GradientMesh, n: usize) -> Vec<Node> {
|
||
m.quads(n)
|
||
.into_iter()
|
||
.map(|q| {
|
||
let mut ap = Appearance::default();
|
||
let mut fl = FillLayer::new(Paint::solid(q.color));
|
||
fl.opacity = q.opacity;
|
||
ap.items.push(AppearanceItem::Fill(fl));
|
||
Node::path(NodeId(0), PathData::single(SubPath::polyline(&q.pts, true)), ap)
|
||
})
|
||
.collect()
|
||
}
|
||
|
||
/// One level of evaluation of a live object (non-live nodes return themselves). Blend steps and
|
||
/// envelope results may still contain live objects (e.g. a blend of two meshes).
|
||
pub fn expand_live(n: &Node) -> Vec<Node> {
|
||
expand_live_with(n, None)
|
||
}
|
||
|
||
pub fn expand_live_with(n: &Node, outline: Outliner) -> Vec<Node> {
|
||
expand_live_hooks(n, outline.into())
|
||
}
|
||
|
||
/// [`expand_live_with`] with everything an envelope can ask of the crates above (see [`Hooks`]).
|
||
pub fn expand_live_hooks(n: &Node, hooks: Hooks) -> Vec<Node> {
|
||
match &n.kind {
|
||
NodeKind::Blend { children, spec } => blend_expand(children, spec),
|
||
NodeKind::Envelope { content, kind, fidelity, options, frame, .. } => expand_envelope(content, kind, *fidelity, *options, *frame, hooks),
|
||
NodeKind::Mesh(m) => mesh_quad_nodes(m, 8),
|
||
NodeKind::Repeat(r) => r.expand(),
|
||
_ => vec![n.clone()],
|
||
}
|
||
}
|
||
|
||
/// A live object evaluated into a plain group (keeping the object's id, name and transparency).
|
||
pub fn expanded_group(n: &Node, outline: Outliner) -> Node {
|
||
expanded_group_hooks(n, outline.into())
|
||
}
|
||
|
||
/// [`expanded_group`] with [`Hooks`].
|
||
pub fn expanded_group_hooks(n: &Node, hooks: Hooks) -> Node {
|
||
let children = expand_live_hooks(n, hooks).into_iter().map(Arc::new).collect();
|
||
let mut g = Node::new(n.id, NodeKind::Group { children, clip: false });
|
||
g.name = n.name.clone();
|
||
g.visible = n.visible;
|
||
g.locked = n.locked;
|
||
g.opacity = n.opacity;
|
||
g.blend = n.blend;
|
||
g.isolate = n.isolate;
|
||
g.knockout = n.knockout;
|
||
// Knocking out opaque blend steps changes nothing: don't make the outputs work for it.
|
||
if matches!(n.kind, NodeKind::Blend { .. }) && g.knockout == crate::Knockout::On && !crate::blend::knockout_shows(&g) {
|
||
g.knockout = crate::Knockout::Off;
|
||
}
|
||
g.knockout_shape = n.knockout_shape;
|
||
g.mask = n.mask.clone();
|
||
g
|
||
}
|
||
|
||
/// Recursively replace every live object in `n` by plain geometry (for exporters).
|
||
pub fn expand_deep(n: &Node, outline: Outliner) -> Node {
|
||
expand_deep_hooks(n, outline.into())
|
||
}
|
||
|
||
/// [`expand_deep`] with [`Hooks`].
|
||
pub fn expand_deep_hooks(n: &Node, hooks: Hooks) -> Node {
|
||
let mut out = if is_live(n) { expanded_group_hooks(n, hooks) } else { n.clone() };
|
||
if let Some(ch) = out.children_mut() {
|
||
for c in ch.iter_mut() {
|
||
if subtree_has_live(c) {
|
||
*c = Arc::new(expand_deep_hooks(c, hooks));
|
||
}
|
||
}
|
||
}
|
||
out
|
||
}
|
||
|
||
/// Does `n` or any descendant need live evaluation?
|
||
pub fn subtree_has_live(n: &Node) -> bool {
|
||
let mut any = false;
|
||
n.walk(&mut |c| any |= is_live(c));
|
||
any
|
||
}
|
||
|
||
/// Largest stroke outset in a subtree (for visual bounds of envelopes).
|
||
pub(crate) fn max_outset(nodes: &[Arc<Node>]) -> f64 {
|
||
let mut o = 0.0f64;
|
||
for n in nodes {
|
||
n.walk(&mut |c| o = o.max(c.appearance.outset()));
|
||
}
|
||
o
|
||
}
|
||
|
||
#[cfg(test)]
|
||
mod tests {
|
||
use super::*;
|
||
use vectorcraft_geom::shapes;
|
||
|
||
fn rect_node(x: f64, y: f64, w: f64, h: f64, c: Color) -> Arc<Node> {
|
||
Arc::new(Node::path(NodeId(1), shapes::rectangle(Rect::new(x, y, x + w, y + h)), Appearance::basic(Paint::solid(c), Paint::None, 0.0)))
|
||
}
|
||
|
||
#[test]
|
||
fn lerp_path_equalises_anchor_counts() {
|
||
let a = shapes::rectangle(Rect::new(0.0, 0.0, 10.0, 10.0));
|
||
let b = shapes::ellipse(Rect::new(0.0, 0.0, 10.0, 10.0));
|
||
let t = lerp_path(&a, &shapes::polygon(Point::new(5.0, 5.0), 5.0, 7, 0.0), 0.5);
|
||
assert_eq!(t.subpaths[0].anchors.len(), 7);
|
||
let m = lerp_path(&a, &b, 0.0);
|
||
assert_eq!(m.subpaths[0].anchors.len(), 4);
|
||
}
|
||
|
||
#[test]
|
||
fn blend_steps_and_colours() {
|
||
let keys = vec![rect_node(0.0, 0.0, 10.0, 10.0, Color::BLACK), rect_node(100.0, 0.0, 10.0, 10.0, Color::WHITE)];
|
||
let out = blend_expand(&keys, &BlendSpec { spacing: BlendSpacing::Steps(3), ..Default::default() });
|
||
assert_eq!(out.len(), 5);
|
||
let mid = out[2].appearance.fill_paint().color().unwrap().to_rgb()[0];
|
||
assert!((mid - 0.5).abs() < 1e-3);
|
||
}
|
||
|
||
#[test]
|
||
fn coons_rect_is_identity() {
|
||
let c = Coons::from_path(&shapes::rectangle(Rect::new(0.0, 0.0, 100.0, 50.0))).unwrap();
|
||
let p = c.eval(0.25, 0.5);
|
||
assert!((p.x - 25.0).abs() < 1e-6 && (p.y - 25.0).abs() < 1e-6, "{p:?}");
|
||
}
|
||
|
||
#[test]
|
||
fn maps_go_on_past_the_content_box() {
|
||
// A stroke outline reaches past the box: a flat mesh and a rectangle stay the identity there.
|
||
let r = Rect::new(0.0, 0.0, 100.0, 100.0);
|
||
let p = grid_eval(2, 2, &grid_points(r, 2, 2), -0.05, 1.1);
|
||
assert!((p.x + 5.0).abs() < 1e-6 && (p.y - 110.0).abs() < 1e-6, "{p:?}");
|
||
let c = Coons::from_path(&shapes::rectangle(r)).unwrap().eval(1.05, -0.1);
|
||
assert!((c.x - 105.0).abs() < 1e-6 && (c.y + 10.0).abs() < 1e-6, "{c:?}");
|
||
}
|
||
|
||
#[test]
|
||
fn grid_identity() {
|
||
let r = Rect::new(0.0, 0.0, 100.0, 100.0);
|
||
let pts = grid_points(r, 3, 4);
|
||
let p = grid_eval(3, 4, &pts, 0.37, 0.81);
|
||
assert!((p.x - 37.0).abs() < 1e-6 && (p.y - 81.0).abs() < 1e-6, "{p:?}");
|
||
}
|
||
|
||
#[test]
|
||
fn mesh_insert_and_remove_lines() {
|
||
let mut m =
|
||
GradientMesh::for_path(&shapes::rectangle(Rect::new(0.0, 0.0, 100.0, 100.0)), 1, 1, Color::BLACK, MeshAppearance::Flat, 0.0).unwrap();
|
||
let i = m.add_lines_at(Point::new(30.0, 60.0)).unwrap();
|
||
assert_eq!((m.rows, m.cols), (2, 2));
|
||
assert!(m.points[i].p.distance(Point::new(30.0, 60.0)) < 0.5, "{:?}", m.points[i].p);
|
||
assert!(m.remove_point_lines(i));
|
||
assert_eq!((m.rows, m.cols), (1, 1));
|
||
}
|
||
}
|