CRITICAL PERFORMANCE FIX: Converting SVG paths to Polygons on every mouse
move was causing severe lag. Cache the polygons per region ID.
Problem:
- pathToPolygon() samples 50 points using getTotalLength() + getPointAtLength()
- This was being called for EVERY region on EVERY mouse move
- For world map with ~200 regions, this was 200 expensive conversions per frame
- Completely unusable performance
Solution:
- Cache Polygon objects in a Map<regionId, Polygon>
- Only compute polygon once per region, reuse on subsequent detections
- Clear cache when map data changes (continent/map selection)
Performance improvement:
- Before: ~200 polygon conversions per mouse move
- After: ~200 polygon conversions total (one-time cost), 0 per mouse move
- Detection now runs at full frame rate
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
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