M3: Width tool depth and the new-art appearance template (M3.64, M3.65)

[bflatastic]

Part of M3 (Paint & appearance). The Width tool gets Width Point Edit, multi-select, Alt-copy and discontinuous points, and new art can inherit an appearance template.

• M3.64: Width tool depth.
  • Width Point Edit: double-clicking a width point opens it (dialog widthPoint, or ui.widthPointEdit {id, index}). It has Side 1, Side 2 and Total Width with a link, Adjust Adjoining Width Points, and Delete.
  • Multi-select: Shift-click adds or removes width points. Dragging one of several selected points moves or widens them all in one undo step; Delete removes them all.
  • Copy: Alt-dragging a point's centre copies it (stroke.widthPoint.copy {id, index, t}).
  • Discontinuous points: dropping a point onto another makes a discontinuous point, a step in width. The shared stroke geometry draws the step, and flipping a profile swaps its sides.
  • Commands: stroke.widthPoint.set {adjustAdjoining?}, stroke.widthPoint.remove {indices}. document.inspect reports strokeOptions.widthPoints.
  • Model: a profile may hold two points at the same position. There are no new fields, and there's a native round-trip test.
• M3.65: new-art appearance template.
  • Model: PaintDefaults gains appearance, opacity, blend, style and inherited. The preferences gain newArtBasic (on by default).
  • Nothing selected:
    • stroke.set and stroke.setAdvanced set up the next object drawn (cap, join, dash, arrowheads, profile…). Shapes, lines, grids, Pen, Pencil and Curvature all use it.
    • graphicStyle.apply (with add too) sets the template. New art is linked to the style, and the style's gradients land on the new object's bounds.
  • New Art Has Basic Appearance: turned off (appearance.setNewArtBasic {on?}, the Appearance panel's flyout), new art takes the last selection's whole appearance: every fill, stroke, effect, opacity and blend mode.
  • Other commands: paint.default resets the template, and appearance.newArt reports it.
  • Panels: with nothing selected, the Stroke and Appearance panels show the template, and clicking a graphic style applies it to the template.

docs/mcp.md and docs/control-protocol.md cover the commands and dialog.

Known limits:

• Editing a selected object's stroke doesn't carry its cap or dash to new art; weight always does.
• Clicking a style in the graphic style library panel with nothing selected only adds it to the document.

Checks

Rebased onto d974093 (#57). cargo xtask ci passes all 7 steps (fmt, clippy, test, assets, brands, layers, wasm): 1,852 tests, 0 failed.

New tests:

• tool multi-select and drag;
• Alt-drag adds one point;
• the step renders (area check and a pixel probe);
• the dialog in a headless frame, without stretching with the screen;
• a round cap plus dash carries to a new rectangle;
• with the option off, two fills and a shadow carry over;
• preferences round-trip;
• a headless Appearance panel frame.

🤖 Generated with Claude Code