Change linear gradient implementation to CAGradientLayer for iOS new arch#3
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SzymczakJ merged 5 commits intoApr 22, 2026
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Migrated react-native-linear-gradient's iOS implementation from CPU-rasterized UIGraphicsImageRenderer (which drew a CGImage bitmap and set it as layer.contents) to GPU-composited CAGradientLayer.
Benefits
No main-thread rasterization. Old path stalled the main thread on every draw; new path is composited by the render server, which is much faster(40 ms of CPU cost to almost 0 ms) .
Cheap resizes / reflows. Bounds changes (rotation, keyboard, bottom sheet expand, Reanimated layouts) are a single property assignment — no bitmap re-allocation.
No re-raster on prop tweaks. Color or stop changes are metadata updates, not full redraws.
No peak-memory spikes during redraw. Transient CPU bitmap allocations are gone; less allocator churn and heap fragmentation.
Notes on memory
Old implementation had to allocate a lot of memory for CG raster data, now when CAGradientLayer handles everything on GPU that cost is gone(now it just needs small data structures for GPU communication). This gives us ~4MiB memory save on each screen sized gradient.