Merge pull request #3145 from adambelis/feat/width-smooth-profile

Width profiles run smooth between their points

docs/target-app-parity.md

@@ -1315,7 +1315,7 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
     Cmd/Ctrl-click on the Gradient panel's Gradient Fill box or on the Tools panel's Gradient button resets the gradient of the active Fill or Stroke to the linear White, Black gradient, as one undo step ([Default keyboard shortcuts](https://web.archive.org/web/20260726060015/https://helpx.adobe.com/illustrator/using/default-keyboard-shortcuts.html)).
     With a gradient stop or a freeform gradient point selected, Alt-clicking a color swatch in the Swatches panel recolors it instead of the inactive Fill or Stroke.
   - **Freeform gradient colors in their own model:** Object ▸ Expand and Object ▸ Create Gradient Mesh (`object.mesh.create`) mix a freeform gradient's points in the color model they share: points of C50 M20 Y0 K10 give mesh points of C50 M20 Y0 K10, and RGB points keep their values in a working RGB space other than sRGB. The canvas, the gradient chips and the SVG, PDF, EPS and EMF writers mix the points in that model too. PDF and EPS write a gradient whose points are all CMYK, or all Gray in a CMYK file, as a CMYK image, which PDF's Output settings convert as they convert any CMYK image. Points in different models mix in display RGB (on the canvas in a CMYK document that shows transparency, as the inks of each point), and a CMYK document stores the result of Expand as CMYK through the color settings. Points colored along CMYK stops (`paint.editGradient {stops}`, or a CMYK gradient switched to freeform) are CMYK, and so are a point `paint.freeform.splitLine` adds between CMYK points and a point `paint.freeform.addPoint` adds without `color` to CMYK points. Public reference: [Gradients](https://web.archive.org/web/20250714042311/https://helpx.adobe.com/illustrator/using/gradients.html) and [Meshes](https://web.archive.org/web/20250812201019/https://helpx.adobe.com/illustrator/using/meshes.html), which do not state how colors in different models mix; the rule is VectorCraft's own.
-  - **Strokes:** one stroke-geometry module shared by the canvas, SVG, PDF and Outline Stroke; dotted lines (zero-length dashes draw dots or squares); arrowheads with hollow outlines, tip-on-end or extend-past-end alignment and one opacity for line and head. SVG and PDF export arrowheads, width profiles, brushes and aligned strokes exactly as the canvas draws them; Outline Stroke and the live Outline Stroke effect outline every stroke item as drawn (dashes, heads, profiles, alignment); dashes can be fitted to corners and path ends; width profiles carry through dashes, and their corners take the join. The Stroke panel edits type's character strokes, follows the stroke units (its weight presets are round values in that unit: `0.25 mm`, `0.0625 in`, `1 px`, #426; fields show four decimals in mm, cm and inches, three in points), shows mixed values blank and opens from the Control bar. A width profile library, thirty-one more arrowheads (among them Line Arrow: two arms of the head's weight (stroke weight × arrowhead scale, at least 0.25 pt: the line's weight at 100 % for lines of 0.25 pt or more) at right angles, cut square, #5421), and Width Point Edit with multi-select and discontinuous points. Visual bounds and clicks cover the whole painted stroke. Scale Strokes & Effects, Scale Corners and Use Preview Bounds work everywhere, and new art inherits stroke options, a graphic style or the whole last appearance.
+  - **Strokes:** one stroke-geometry module shared by the canvas, SVG, PDF and Outline Stroke; dotted lines (zero-length dashes draw dots or squares); arrowheads with hollow outlines, tip-on-end or extend-past-end alignment and one opacity for line and head. SVG and PDF export arrowheads, width profiles, brushes and aligned strokes exactly as the canvas draws them; Outline Stroke and the live Outline Stroke effect outline every stroke item as drawn (dashes, heads, profiles, alignment); dashes can be fitted to corners and path ends; width profiles carry through dashes, and their corners take the join. The Stroke panel edits type's character strokes, follows the stroke units (its weight presets are round values in that unit: `0.25 mm`, `0.0625 in`, `1 px`, #426; fields show four decimals in mm, cm and inches, three in points), shows mixed values blank and opens from the Control bar. A width profile library, thirty-one more arrowheads (among them Line Arrow: two arms of the head's weight (stroke weight × arrowhead scale, at least 0.25 pt: the line's weight at 100 % for lines of 0.25 pt or more) at right angles, cut square, #5421), and Width Point Edit with multi-select and discontinuous points. Visual bounds and clicks cover the whole painted stroke. Scale Strokes & Effects, Scale Corners and Use Preview Bounds work everywhere, and new art inherits stroke options, a graphic style or the whole last appearance. A width profile's sides run as a smooth C1 curve between the width points (a monotone cubic Hermite, Fritsch–Carlson, with the one-sided three-point PCHIP slope at the profile's ends and flat either side of a step), sampled adaptively along the path (two samples per profile segment, refined where the width bends, and leaning on dense path flattening) so straight runs draw it too; added samples offset along the source curve's exact tangent, not the flattened chord, so high zoom follows the true width; the sampled edges are fitted with G1 cubics within a tenth of the flattening tolerance (0.001 pt at the default 0.01 pt) rather than one cubic per flatten step, so exports stay close to a uniform stroke's path data; a point reshapes the curve as far as its neighbours' neighbours (their slopes depend on it), and coincident points still step.
   - **Brushes (part of #852):** double-clicking a brush in the Brushes panel (or the panel menu's Brush Options…) opens Calligraphic Brush Options (Name; Angle, Roundness and Size, each Fixed, Random, Pressure, Tilt, Bearing or Rotation with its Variation; live previews of the nib and of a light–heavy–light stroke) or Bristle Brush Options (Shape and the bristle sliders); OK edits the brush and every stroke painted with it. The Paintbrush records the pen pressure along each stroke (kept with the path, saved, and joined when a stroke continues a path); a Calligraphic value on Pressure goes from value − variation at the lightest pressure to value + variation at the heaviest, on the canvas and in SVG, PDF and the other exports. Brushes saved before keep their look. Scatter Brush Options (Size, Spacing, Scatter and Rotation, each Fixed, Random between two values, Pressure from the first at the lightest pressure to the second at the heaviest, Tilt, Bearing or Rotation; Rotation relative to Page or Path), Art Brush Options (Width, Scale Proportionately, Stretch to Fit Stroke Length or Stretch Between Guides with the guides' start and end, the four Directions, Flip Along and Across, Overlap) and Pattern Brush Options (Scale, Spacing, the five tiles shown, Flip Along and Across, Stretch to fit, Add space to fit or Approximate path) each have Colorization (None, Tints, Tints and Shades, Hue Shift with its Key Color picked from the art's colours) and a live stroke preview; values from files and commands are clamped to their ranges. Art Brush Options › Overlap places art on each run between sharp corners so folds do not overlap (`ArtBrush.overlap`; `art_brush_overlap_splits_at_corners`). Still to come: Stylus Wheel, pen pressure on macOS where the windowing layer reports none, and tilt, bearing and rotation for Art, Pattern and Bristle brushes and on native Wayland and the web.
     Under Tints and Tints and Shades, art in black ink alone goes by its ink amount, and a process or gray stroke color's tints and shades stay in that color's model; these are VectorCraft's own rules.
     Type in a scatter brush's art takes the brush's colorization as its paths do: Tints, Tints and Shades and Hue Shift recolor the characters' solid fills and strokes in each copy the brush draws, and Brush Options' Key Color list, whose first color is Hue Shift's default key, counts the characters' fills and their strokes wider than 0. The Brushes page says that a scatter, art or pattern brush takes its colors from the current stroke color and the brush's colorization method (<https://web.archive.org/web/20241230205225/https://helpx.adobe.com/illustrator/using/brushes.html>) and does not mention type there; recoloring the characters' paints like the art's fills and strokes is VectorCraft's own rule. The Symbol Stainer mixes the characters' strokes of type toward the stain as it mixes their fills. Evidence: `tests::scatter_colorization_recolors_type`, `tests::art_colors_list_the_most_used_first`, `tests::stain_mixes_type_strokes_too` (vectorcraft-brush).
@@ -2183,6 +2183,7 @@ Edit › Copy and Cut put the selected ruler guides on the clipboard, with the s
 | 2026-10-22 | minor | G2: Effect › Sketch › Conté Crayon (Foreground Level, Background Level, Texture, Scaling, Relief, Light Direction, Invert; a black crayon in the dark areas and a white one in the light areas on textured mid-grey paper; ranges and defaults unverified VectorCraft choices); measured Photoshop-style filters 57/57, the Effect Gallery remains (4–6 h); area score unchanged (49%, estimated). |
 | 2026-10-22 | minor | File formats: Affinity import gains master pages, tables, paragraph formats, text scale, shadows, glows, outlines (also on stroked shapes), overlays, underlines, strikethrough and editable embedded documents, strokes styled None left out, CMYK pixel layers through the document's CMYK profile, text placed as Affinity places it (AF.5, from storytold/designcraft#291); synthetic, corpus and local-thumbnail tests; score and hours unchanged (estimated). Hostile files stay bounded: one budget for the whole read (layers, pixels, characters, table cells, embedded documents included), a work budget for overlays, capped master page copies, objects past `MAX_COORD` left out; the import fuzzer and limit tests cover tables, paragraphs, effects, overlays, master pages, CMYK pixels and embedded documents. |
 | 2026-10-22 | minor | Recolor Artwork Edit chips scroll within the available screen height (#3416); small palettes retain their tab height; scores and estimates unchanged. |
+| 2026-10-21 | minor | Width-profile outlines offset samples added inside a flattened chord along the source curve's exact tangent, so a zoomed outline no longer jogs at flatten vertices; a regression test covers added samples. Scores and estimates unchanged. |
 | 2026-10-22 | minor | Font pickers list recently applied families first (#3515), using the existing recent-font limit; search, filters, previews and keyboard selection share the same rows. Scores and estimates unchanged. |
 | 2026-10-21 | minor | Plug-ins: filters keep data with the document (`documentData`), as its foreign data, so the native file needs no section of its own (G17); engine and unit regressions. Scores and hours unchanged. |
 | 2026-10-21 | minor | Print: PDF/X-1a and PDF/X-3 flattening in a CMYK document rasterizes as ink amounts, so CMYK colours under an image with see-through pixels keep their numbers, K included, instead of going through RGB (#2160); own-fixture test; scores and hours unchanged (estimated) |
@@ -2199,6 +2200,7 @@ Edit › Copy and Cut put the selected ruler guides on the clipboard, with the s
 | 2026-10-21 | minor | Snap to Glyph (#3124) removed from View navigation missing lists and menu stubs; scores and hours unchanged at this rounding |
 | 2026-10-21 | minor | Type core: System Layout (Character panel menu, whole document, off by default) is done; scores and hours unchanged |
 | 2026-10-22 | minor | Ruby (ふりがな) for live text: `type.ruby` sets/removes a reading over a byte range, above or below (right of the column in vertical type), aligned, sized and overhanging or squeezed; saved natively, laid out with line growth, drawn on the canvas and in SVG/PDF (outlines where ruby is present); scores and hours unchanged |
+| 2026-10-23 | minor | Width-profile outlines sample adaptively: two samples per profile segment, refined where the width bends, and only where the flattened path does not already sample the width. The sampled edges are fitted with G1 cubics within a tenth of the flattening tolerance (0.001 pt by default) instead of one cubic per flatten step. On the reviewer's 1,500-ellipse fixture (20–200 pt ellipses, 3–12 pt weights) the PDF falls to 3.59 MB and the SVG to 6.79 MB (reported main baselines 4.48 MB and 9.30 MB, about 0.80× and 0.73×), and `profiled_outlines_stay_compact` guards the path-element count. Scores and estimates unchanged. |
 | 2026-10-21 | minor | 3D: original Standard, Diffuse, Top Left and Right lighting presets; command access, effective-setting recognition and preview/history; scores and estimates unchanged |
 | 2026-10-21 | minor | Properties: one selected clip group has Edit Clipping Path and Edit Contents at the top of the panel (public doc cited) (G1). Scores and hours unchanged. |
 | 2026-10-21 | minor | Print: the Print dialog's Media list carries the Japanese papers — JIS B4 (257 × 364 mm), JIS B5 (182 × 257 mm) and JIS B6 next to the ISO B4/B5, which keep their ISO 216 sizes, plus はがき, 往復はがき, 封筒 長形3号/長形4号/角形2号/角形3号 and 四六判; the JSON id or the dialog label names a paper, any case and spacing. Print score and hours unchanged. |
@@ -2212,6 +2214,7 @@ Edit › Copy and Cut put the selected ruler guides on the clipboard, with the s
 | 2026-10-19 | minor | Plug-ins: parameters with labels, units, help, groups and conditions in their dialogs, `string` and `numberList` types, up to 256 per plug-in (G17); manifest and kittest dialog regressions. Scores and hours unchanged. |
 | 2026-10-19 | minor | Plug-ins: exporter plug-ins add write-only file formats to Export As and `document.export` (G17); engine, ABI and headless Export As regressions. Scores and hours unchanged. |
 | 2026-10-19 | minor | Libraries panel: the list fills the panel and scrolls (also while a drag nears its edges); items drag before or after others of their kind and into or out of groups, and groups drag by their headers (`library.moveItem` `before`/`after`, `library.moveGroup`). Scores and estimates unchanged. |
+| 2026-10-19 | minor | Width profiles run as a smooth C1 curve between their points (a monotone cubic Hermite, Fritsch-Carlson) instead of straight lines, sampled along the path so the outline follows it on straight runs; steps between coincident points still step. Regression tests cover easing, monotonicity, locality and steps. Scores and estimates unchanged. |
 | 2026-10-19 | minor | Cache status-readout sample widths per UI, language, document unit and pixels per point; regressions check reuse across live frames and refresh after display-setting changes. Scores and estimates unchanged. |
 | 2026-10-19 | minor | Status messages and readouts use stable responsive allocations sized for localized labels and ordinary coordinates. Contributor original-file acceptance confirmed; scores and estimates unchanged. |
 | 2026-10-19 | minor | Cached canvas dimensions match the renderer limit before cache-key creation, view construction and worker submission. Regression coverage; scores and estimates unchanged. |