iwb_canvas_engine 0.2.0

Scene-based canvas engine for Flutter: model, rendering, input, JSON serialization.

Unreleased

0.2.0 - 2026-02-04

• Breaking: remove legacy package:iwb_canvas_engine/iwb_canvas_engine.dart entrypoint; use basic.dart or advanced.dart.
• SceneView: imageResolver is now optional; add optional configuration parameters (pointerSettings, dragStartSlop, nodeIdGenerator) for the internally owned controller.
• SceneController: breaking: remove direct setters for mode/drawTool/drawColor (use setMode/setDrawTool/setDrawColor); add selection helpers (setSelection, toggleSelection, selectAll) and selection geometry getters (selectionBoundsWorld, selectionCenterWorld); add mutate(...) and getNode/findNode.
• Nodes: add AABB-based topLeftWorld / fromTopLeftWorld helpers for RectNode, ImageNode, and TextNode.
• Breaking: remove legacy aliases SceneNode.aabb and schemaVersion.
• Action events: document payload schemas and add typed payload accessors.
• More accurate hit-test for rotated rect/image/text nodes; hitPadding now affects them.
• Internal: tighten repaint notification invariants and add a debug-only guard that disables drag-move buffering on external structural scene mutations.
• Refactor input internals into vertical slices with explicit boundary contracts, strict import boundary checks, and slice-level regression tests.
• Tooling: add invariant registry + coverage checks to ensure every invariant is enforced by a test and/or tool check.
• Docs: add CODE_REVIEW_CHECKLIST.md for maintainers.
• Docs/tooling: keep dart doc warning-free via dartdoc_options.yaml.

0.1.0 - 2026-02-03

Performance

• Cache PathNode local paths to reduce selection rendering overhead.
• Avoid extra scene traversal when rendering selections.
• Simplify selection halo rendering to avoid expensive path unions/layers.

Serialization (breaking)

• JSON import/export is now v2-only (schemaVersion = 2). v1 scenes are not supported.

Selection transforms

• Add horizontal flip alongside vertical flip.
• Replace rotate/flip/drag-move action events with ActionType.transform and payload.delta (2×3 affine matrix).
• Breaking: ActionType.rotate and ActionType.flip removed.

Stage 1 — Public API split (basic vs advanced)

• Add basic.dart entrypoint with a minimal public surface.
• Add advanced.dart entrypoint that exports the full API.
• Document public API split and usage in README.

Stage 2 — SceneController mutations

• Add SceneController mutation helpers (addNode, removeNode, moveNode).

Stage 3 — notifySceneChanged invariants

• Enforce selection cleanup on notifySceneChanged() after external mutations.

Stage 4 — NodeId generation

• Use per-controller NodeId seed; document nodeIdGenerator.

Stage 5 — SceneView without external controller

• Allow SceneView without an external controller + onControllerReady.

Stage 6 — Locked/transformable rules

• Define locked/transformable selection rules and document behavior.

Stage 7 — Public API docs

• Add Dartdoc for SceneController public methods and streams.

Stage 8 — Example app updates

• Update example app to use basic.dart and demonstrate JSON export/import.

Selection rendering

• Draw selection outlines using each node's geometry instead of the combined AABB.
• Render selection as a halo around the node geometry.

Backlog item delivered

• Add viewport culling in ScenePainter to skip offscreen nodes.

0.0.3

• Publish web demo (Flutter Web) to GitHub Pages.
• Improve README links for pub.dev.

0.0.2

• Declare supported platforms on pub.dev.
• Add documentation link to GitHub Pages.

0.0.1

Initial release.

• Scene model (layers, nodes, background, camera)
• Rendering via ScenePainter and SceneView
• Input handling via SceneController (move/draw modes)
• JSON v1 import/export with validation
• Example app and unit tests