SketchStudio shapes, rotation, fuse, paste

name: SketchStudio shapes upgrade overview: Extend Sketch Studio (via Novolis.Avalonia.Controls) with speech-bubble / text / textbox tools, rotation, group-fuse, clipboard image paste, and a pen fix so freehand is not yanked onto existing vertices while drawing. todos:

• id: model-json

content: Extend StrokeShape (Kind, Rotation, GroupId, Text, Image) + SketchJson v2 round-trip status: completed

• id: pen-meetup

content: Skip meetup snap during Pen freehand drag status: completed

• id: primitives-tools

content: SpeechBubble primitive + Text/TextBox/SpeechBubble tools, render/hit-test/edit overlay status: completed

• id: rotation

content: RotationDegrees + rotate grip; transform-aware hit-test/resize status: completed

• id: fuse

content: FuseSelection/UngroupSelection + group-aware selection/transforms status: completed

• id: paste-ui

content: SketchStudio Ctrl+V/toolbar paste image; toolbar shortcuts; export draw path status: completed

• id: tests-verify

content: Unit tests + ProjectRef build/run SketchStudio + nuget-only verify status: completed isProject: false

Defaults (locked)

Work lands primarily in `d:\novolis\novolis-avalonia\src\Novolis.Avalonia.Controls\` (source of truth), with toolbar/shortcuts/paste in `d:\novolis\novolis-apps\src\SketchStudio\MainWindow.cs`. Dogfood `SketchLab` gets matching tool buttons only if cheap (same Controls APIs).

Local iteration: build via `d:\novolis\novolis-governance\build\Novolis.Platform.slnx` / ProjectRef mode — do not add sibling ProjectReference in the app csproj. Ship Controls to GPR before consumers restore NuGet-only.

flowchart TB
  tools[New tools Bubble Text TextBox]
  model[StrokeShape fields Kind Rotation GroupId Text Image]
  pen[Pen skips meetup mid-stroke]
  fuse[Fuse / Ungroup GroupId]
  paste[Ctrl+V image element]
  json[SketchJson v2]
  ui[SketchStudio toolbar]
  tools --> model
  pen --> SketchControl
  fuse --> SketchDocument
  paste --> ui
  model --> json
  model --> SketchControl
  ui --> SketchControl

1. Element model + JSON

Extend `StrokeShape` (keep type name for less churn):

• SketchElementKind Kind — Stroke (default), Text, TextBox, Image
• double RotationDegrees
• string? GroupId
• string? Text, double FontSize (defaults ~16)
• string? ImagePngBase64 (images only; points define the axis-aligned placement rect before rotation)

Bump document/schema to version 2 in `SketchJson.cs`; omit null/default fields; old files still load as v1 strokes.

Clone / history already snapshot full element lists — ensure new fields copy in Clone().

2. Pen meetup fix

In SketchControl.SnapPointer / pen drag path:

• While _dragMode == Draw and Tool == Pen, do not call SketchMeetup.FindNearestVertex.
• Optionally hide meetup hint during pen drag.
• Line/Spline/shape tools unchanged.

Add a focused unit test or document the behavior in an existing meetup-related test if one exists; otherwise a small SketchMeetup/SnapPointer regression note via control-level test of sampling policy if practical.

3. New primitives and tools

`SketchTool`: add SpeechBubble, Text, TextBox.

`SketchPrimitives.cs`:

• SpeechBubble(a, b) — rounded-rect outline + bottom-left (or bottom-center) triangular tail; closed polyline; unit-tested like Rect/Ellipse.

SketchControl interaction:

• SpeechBubble: same drag as Rect → commit closed stroke (Kind = Stroke).
• Text: press → create Kind=Text element with default "Text" at point; show inline TextBox overlay for edit; Enter/blur commits.
• TextBox: drag AABB → Kind=TextBox with border stroke + fill optional + empty/default text; double-click (or create) opens overlay editor.

Render path in DrawStroke:

• Stroke/SpeechBubble: existing polyline (+ rotation matrix).
• Text / TextBox: draw rotated frame; FormattedText for label; TextBox draws rect then text inset.
• Image: decode cached Bitmap from base64; DrawImage in rotated bounds.

Hit-test / bounds: invert rotation around center before polyline distance / AABB tests (SketchBounds helpers for rotate point / rotated AABB).

4. Rotation

• Selection UI: keep 8 AABB grips; add rotate handle above union center (Select tool).
• Drag applies delta degrees to all selected elements’ RotationDegrees (group-aware).
• Live preview + history push on gesture end (same pattern as move/resize).
• Resize remains axis-aligned in local/unrotated space: inverse-rotate cursor → existing ApplyBoundsTransform → keep RotationDegrees.

5. Fuse (group) / ungroup

`SketchDocument`:

• FuseSelection() — require ≥2 selected; assign shared new GroupId; select all members.
• UngroupSelection() — clear GroupId on selected (and expand to full group first).

Selection UX:

• Clicking any member selects entire group.
• Shift/Ctrl toggle still works at group granularity.
• Move / resize / rotate / delete operate on all group members.
• Shortcuts: Ctrl+G fuse, Ctrl+Shift+G ungroup; toolbar icons in SketchStudio.

6. Picture paste (SketchStudio host)

In `MainWindow.cs` / thin API on SketchControl:

• PasteImage(byte[] pngOrRaster, SketchPoint centerWorld, double maxEdge) creates Kind=Image with placement rect, selects it, records history.
• Host: on Ctrl+V, try clipboard bitmap (Avalonia IClipboard / DataFormats); if image → paste; if not, no-op (do not steal Select tool’s V key — paste uses Ctrl+V only; Select stays V alone).
• Toolbar “Paste image” button next to Copy PNG/SVG.

Export (SketchExport): include images and text in PNG/SVG when feasible (PNG via existing render path if it draws through SketchControl.Render or shared draw helper; SVG: embed image as base64 <image>, text as <text>).

7. SketchStudio chrome

Toolbar additions: Speech bubble, Text, TextBox; Fuse / Ungroup; Paste image; shortcuts in status help.

Status strings for new tools. No XAML — same code-built panels as today.

8. Tests and verify

Under `d:\novolis\novolis-avalonia\tests\Novolis.Avalonia.Unit\Controls\`:

• SpeechBubble point count / closed / bounds
• Rotate point helpers
• Fuse/Ungroup GroupId + selection expansion
• SketchJson round-trip for Kind/Text/Rotation/GroupId/Image

Build/test:

dotnet test d:\novolis\novolis-avalonia\tests\Novolis.Avalonia.Unit\Novolis.Avalonia.Unit.csproj -p:NovolisUseProjectReferences=true
dotnet run --project d:\novolis\novolis-apps\src\SketchStudio -p:NovolisUseProjectReferences=true
pwsh -File d:\novolis\novolis-governance\scripts\verify-nuget-only.ps1

After merge: publish Novolis.Avalonia.Controls to GitHub Packages so SketchStudio’s floating 2026.1.* picks up the APIs without local feeds.