Colors were being lost during resize operations because toDiagramEntity
extracted color from material.diffuseColor, which is no longer used after
the emissiveColor rendering optimization (commit c7887d7).
Root Causes:
1. Rendering system changed from diffuseColor to emissiveColor
2. Material properties unreliable when materials are shared
3. Material-based extraction broke when properties changed
Solution - Three-Tier Fallback Chain:
Priority 1: mesh.metadata.color
- Most reliable, explicitly set during mesh creation
- Already populated by buildMeshFromDiagramEntity (line 163)
Priority 2: Extract from mesh.sourceMesh.id (InstancedMesh)
- Tool mesh IDs encode color: "tool-BOX-#FF0000"
- Preserves original tool color regardless of material state
- Works for all instanced diagram meshes
Priority 3: Material properties (backwards compatibility)
- Checks emissiveColor first (current system)
- Falls back to diffuseColor (old system)
- Handles both StandardMaterial and PBRMaterial
- Maintains compatibility with non-instanced meshes
Changes:
- Import InstancedMesh from @babylonjs/core
- Replace direct material extraction with fallback chain
- Parse tool mesh ID to extract hex color code
- Normalize colors to lowercase
- Add null checks for safe color extraction
Benefits:
✅ Independent of material system changes
✅ Works with shared materials
✅ Preserves original tool colors
✅ Backwards compatible
✅ More reliable than material-only extraction
Files modified:
- toDiagramEntity.ts: Implement fallback chain for color extraction
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
Michael Mainguy
43100ad650