perf: FIT-1295: Add React memoization to hot rendering paths#9261
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perf: FIT-1295: Add React memoization to hot rendering paths#9261
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Add useCallback, useMemo, and React.memo to components that are rendered frequently to prevent unnecessary re-renders. Changes: - VideoRegions.jsx: Extract Shape onClick handler with useCallback, memoize selected regions filter - RegionLabels.tsx: Add memoized LabelItem component, memoize label extraction - Choices.jsx: Extract Select onChange handler with useCallback - PolygonRegion.jsx: Extract Edge handlers with useCallback, memoize flattenedPoints and lineProps These optimizations reduce function recreation on each render and help React's reconciliation process skip unnecessary updates.
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| // Memoized label item component to prevent unnecessary re-renders | ||
| const LabelItem = memo(({ label, showComma }: { label: any; showComma: boolean }) => { | ||
| const color = label.background || "#000000"; |
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rather than #000000 lets have a safe default from our css tokens
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yyassi-heartex
approved these changes
Jan 26, 2026
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This PR is stale because it has been open 45 days with no activity. Remove |
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Problem
Inline function handlers are recreated on every render, causing child components to receive new prop references and re-render unnecessarily. This is particularly impactful in hot paths like VideoRegions, Choices, and PolygonRegion.
Solution
Add
useCallbackfor event handlers anduseMemofor computed values to prevent unnecessary re-renders.Files Changed
web/libs/editor/src/tags/object/Video/VideoRegions.jsxweb/libs/editor/src/tags/control/Choices.jsxweb/libs/editor/src/regions/PolygonRegion.jsxweb/libs/editor/src/components/SidePanels/DetailsPanel/RegionLabels.tsx