Merge pull request #7240 from dotCooCoo/feat/smooth-reach-overlay

Smooth tool: the drag shows the band the tool smooths

docs/target-app-parity.md

@@ -1040,8 +1040,8 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
   - **Drawing:** Pen, Curvature, anchor tools, Pencil, Paintbrush, Blob Brush, Smooth, Path Eraser, Join. Direction handles dragged with Direct Selection or the Anchor Point tool snap to smart guides, and Shift keeps them at 45° steps from their anchor. The Pen continues any open path from the end clicked, and while drawing, a click on an end of another open path joins the two into one (#776). The Curvature tool edits any selected path, whatever drew it, keeping its shape except where edited (#798): a click on a point makes it current and a drag moves it, re-curving only its two segments; double-click, or Alt-click on any point but an end of an open path, toggles it smooth or corner and Delete removes it; a click on a segment adds a point without changing the shape; with an end of an open path current, clicks go on from it and its other end closes it (`path.curvatureEdit`). An Alt-click on an end of a selected open path makes that end current without changing it, so the next click goes on from it, as [the help page](https://helpx.adobe.com/illustrator/desktop/draw-shapes-and-paths/draw-shapes/draw-shapes-with-the-curvature-tool.html) describes for continuing a path; an Alt-click that starts a new path places a corner point, as later Alt-clicks do. Every point a drawing tool places snaps to Smart Guides through one snapper (#506): the Pen's and Curvature tool's anchors, the Pencil's ends, the shape tools' start and dragged corner or radius (Rectangle, Rounded Rectangle, Ellipse, Polygon, Star, Line Segment, Arc, Spiral, the grids), the Type tool's click and frame, a new artboard's corners. A filled Pencil path keeps a stroke of None (#1804, part of #1679). While a Pencil or Paintbrush stroke is drawn back to within Close Paths When Ends Are Within of its start, the cursor shows the closing ring and a release there closes the path, as [Draw straight lines with the Pencil tool](https://helpx.adobe.com/illustrator/desktop/draw-shapes-and-paths/draw-shapes/draw-straight-lines-with-the-pencil-tool.html) describes for the Pencil. The [ and ] keys reach the Blob Brush, the Eraser and the Symbolism tools in the app (#1734, part of #1661).
     Blob Brush and Eraser Tool Options' Size is Fixed or Pressure with a Variation (#4590, #3961): with Pressure a pen stroke is Size − Variation wide where it presses lightest and Size + Variation where it presses hardest, and a mouse stroke keeps the Size.
     With the Blob Brush, Shift held during a drag keeps the stroke on the horizontal or vertical line through the press point, whichever is nearer to the pointer (90° steps from the Constrain Angle preference), and the points dragged since Shift went down move to the other line when the pointer crosses to it; the points dragged while Shift is up follow the pointer.
-    With the Blob Brush, Alt held before the press, or pressed before the drag has moved, switches to the Smooth tool, as the reference app's [Default keyboard shortcuts](https://web.archive.org/web/20260726060015/https://helpx.adobe.com/illustrator/using/default-keyboard-shortcuts.html) page lists: the cursor shows the Smooth tool, the drag shows a thin line without the length label, Shift does not constrain it, and the release smooths the selected paths under the drag (`path.smoothRegion`) instead of painting; with nothing selected the release changes no path. A stroke that has moved keeps painting when Alt goes down.
-    Curvature point markers are circular, with no direction handles. While drawing, its own point feedback replaces generic selection markers; existing paths use the selection overlay, including partial selections and Hide Edges. Anchor Size applies, and Direct Selection and Pen retain their handles. The real egui-frame regressions in `crates/ui-egui/src/canvas.rs` verify marker positions, counts and unchanged documents (#1236, in part); the existing-path interpolation request remains open. The curve through the points (`curvature_spline` in `crates/tools/src/draw2.rs`) makes each stretch of three points follow the circle through them: a smooth point's handles lie along that circle's tangent, each `chord / (3 cos²(α/2))` long (α between handle and chord, capped at 90°), and the ends of an open path mirror their neighbour's tangent in their chord, so a J or a U curves evenly, a turn tighter than 30° comes to a point, and uneven spacing doesn't loop; the rubber band, a dragged or inserted point and `path.convertAnchor` to smooth use the same rule, while the Pencil's fitting keeps its own; `tests/draw2.rs` checks that the rubber band is the path the click makes (#1236, in part). The Smooth tool smooths only the stretch of path under the drag (#1547, fixes #1512). A path the Smooth tool changes stays selected whole, and the anchor points and segments selected on it with Direct Selection are deselected. Selected paths the drag does not change keep their selected anchors, and undo restores the earlier selection (`tests/draw2.rs`, `smoothing_a_path_drops_its_direct_selected_anchors`).
+    With the Blob Brush, Alt held before the press, or pressed before the drag has moved, switches to the Smooth tool, as the reference app's [Default keyboard shortcuts](https://web.archive.org/web/20260726060015/https://helpx.adobe.com/illustrator/using/default-keyboard-shortcuts.html) page lists: the cursor shows the Smooth tool, the drag shows a thin line and, with a path selected that it can smooth, the dashed band it smooths, without the length label, Shift does not constrain it, and the release smooths the selected paths under the drag (`path.smoothRegion`) instead of painting; with nothing selected the release changes no path. A stroke that has moved keeps painting when Alt goes down.
+    Curvature point markers are circular, with no direction handles. While drawing, its own point feedback replaces generic selection markers; existing paths use the selection overlay, including partial selections and Hide Edges. Anchor Size applies, and Direct Selection and Pen retain their handles. The real egui-frame regressions in `crates/ui-egui/src/canvas.rs` verify marker positions, counts and unchanged documents (#1236, in part); the existing-path interpolation request remains open. The curve through the points (`curvature_spline` in `crates/tools/src/draw2.rs`) makes each stretch of three points follow the circle through them: a smooth point's handles lie along that circle's tangent, each `chord / (3 cos²(α/2))` long (α between handle and chord, capped at 90°), and the ends of an open path mirror their neighbour's tangent in their chord, so a J or a U curves evenly, a turn tighter than 30° comes to a point, and uneven spacing doesn't loop; the rubber band, a dragged or inserted point and `path.convertAnchor` to smooth use the same rule, while the Pencil's fitting keeps its own; `tests/draw2.rs` checks that the rubber band is the path the click makes (#1236, in part). The Smooth tool smooths only the stretch of path under the drag (#1547, fixes #1512). A path the Smooth tool changes stays selected whole, and the anchor points and segments selected on it with Direct Selection are deselected. Selected paths the drag does not change keep their selected anchors, and undo restores the earlier selection (`tests/draw2.rs`, `smoothing_a_path_drops_its_direct_selected_anchors`). While the Smooth tool drags with a path selected that it can smooth, a dashed outline shows the band it smooths: everything within its radius of the drag (12 screen pixels, VectorCraft's own value), round at both ends; Alt smoothing with the Pencil, Paintbrush and Blob Brush shows the same band.
     While Alt is held during a Paintbrush stroke or before a press with no path selected that the Smooth tool can act on, the Paintbrush shows a closing cursor (a crosshair with a ring), and so does the Pencil with Alt key toggles to Smooth Tool off when Alt is pressed after the drag starts; releasing the mouse button with Alt still held closes the path. Before a Paintbrush press with such a path selected, Alt shows the Smooth cursor, and holding Alt at the press smooths that path with the Smooth tool's radius and Smooth Tool Options' Fidelity. A Pencil drag started with Shift or Alt held draws a straight line instead, which stays open.
     With Shift held at the press, the Pencil draws a straight line from the press point to the pointer at 45° steps from the Constrain Angle, as [Draw straight lines with the Pencil tool](https://helpx.adobe.com/illustrator/desktop/draw-shapes-and-paths/draw-shapes/draw-straight-lines-with-the-pencil-tool.html) describes; pressed on an end of a selected open path, the line continues the path from that end (part of #3799). With Option/Alt held at the press and Alt key toggles to Smooth Tool off, the Pencil draws a straight line at any angle, whose ends snap to Smart Guides, and it stays open when Alt is still held at the release; Shift and Alt together keep the 45° steps (#3799). While Shift or Alt is held before the press, the Pencil shows a straight-line cursor (a crosshair with a short line), and over an end of a selected open path, where the line continues the path, a path-continuation cursor (the same line leaving a small square), as the page describes.
   - **Shapes:** all shape tools (including Flare) and the line, arc, spiral and grid tools. Space held while dragging out a shape, line, arc, spiral or grid moves it at its current size. While a grid is dragged out, Up/Down change its rows (concentric dividers) and Left/Right its columns (radial dividers). A click with a grid tool asks for the size, the divider counts and the grid options (#1377, in part): a skew for each set of dividers, Use Outside Rectangle As Frame or Create Compound Path From Ellipses, and Fill Grid; they are parameters of `shape.rectangularGrid` and `shape.polarGrid`, stay as the tool's options and apply to drags too. A shape just drawn stays adjustable with its tool: its Live Shape widgets drag, a press on its centre point (Show Center) moves the selection with the Selection tool's move arrow, snapping and Alt copy, and a press in the rotate zone just outside a bounding-box corner turns it about the centre with the Selection tool's rotate cursor (#5477; tests `a_shape_tool_moves_the_selection_by_its_centre_point_and_turns_it_from_a_corner` and, through the engine, `shapetools.rs`). A drag on one of its eight bounding-box handles scales it as the Selection tool's handles do, with their cursors and snapping, instead of drawing a new shape from the handle. A shape tool takes a press as a handle's only on the drawn handle square (VectorCraft's own rule: 3 screen points from its centre along each axis at the default Anchor Size, a half point more or less per step; the Selection tool takes 5), so a press just beside a handle still draws (tests `a_shape_tool_scales_the_selection_by_its_bounding_box_handles`, `a_shape_tool_draws_from_a_press_just_beside_a_handle` and `a_shape_tool_scales_the_shape_just_drawn_by_its_bounding_box_handle`). The curve a skew percentage follows and the direction of the radial skew are our own (the public documentation gives neither), and the dialogs have no reference point locator. An ellipse's Pie Start and End Angle and Invert Pie (Transform and Properties panels' Ellipse Properties, `object.setLiveShape {pieStart, pieEnd, invertPie}`) cut it as a pie (#812). With the bounding box showing, the Selection tool shows a selected ellipse's two pie widgets just outside it; dragging one sets its angle in one undo step and double-clicking one makes the ellipse whole again. A live polygon's Polygon Properties there: side count, angle, corner type and radius, radius, side length and Make Sides Equal once an uneven scale has made its sides differ (`object.setLiveShape {sides, polygonAngle, polygonRadius, sideLength, makeSidesEqual}`, part of #812); a star is a plain path, as in Illustrator. The Flare Tool Options last as the tool's options: the next flare dragged out uses them, a click's dialog shows them and double-clicking the tool opens them (part of #812).