fix: putImageData bypassed deferred rendering PageRecorder#1206
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Brooooooklyn merged 3 commits intomainfrom Feb 12, 2026
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fix: putImageData bypassed deferred rendering PageRecorder#1206Brooooooklyn merged 3 commits intomainfrom
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putImageData wrote directly to the main surface canvas, but getImageData reads from the PageRecorder's RecordingSurface in deferred mode. This caused putImageData to have no visible effect since v0.1.89. The fix routes putImageData through PageRecorder.put_pixels(), which creates a fresh recording layer with no clip/transform (per HTML spec, putImageData ignores both). Uses write_pixels_dirty (drawImageRect) instead of write_pixels (SkCanvas::writePixels) because the latter is not recordable by SkPictureRecorder. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Address review feedback: - Add skiac_canvas_put_image_data C++ function using drawImageRect with kSrc blend mode for correct pixel replacement per HTML spec. The previous write_pixels_dirty used SrcOver which composited with existing content instead of replacing it for semi-transparent pixels. - Extract duplicated state restoration logic (begin_recording + restore save_count/clip/transform) into resume_recording() helper, used by both promote_layer() and put_pixels(). Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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write_pixels_dirty (Rust method, FFI binding, and C++ implementation skiac_canvas_write_pixels_dirty) had zero callers after the previous commit replaced all call sites with put_image_data. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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putImageData wrote directly to the main surface canvas, but getImageData
reads from the PageRecorder's RecordingSurface in deferred mode. This
caused putImageData to have no visible effect since v0.1.89.
The fix routes putImageData through PageRecorder.put_pixels(), which
creates a fresh recording layer with no clip/transform (per HTML spec,
putImageData ignores both). Uses write_pixels_dirty (drawImageRect)
instead of write_pixels (SkCanvas::writePixels) because the latter is
not recordable by SkPictureRecorder.
Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com
Note
Medium Risk
Touches core pixel-writing/render recording paths (Rust + C++ FFI) and changes how
putImageDatais applied and layered, which could affect compositing behavior across backends. Scope is contained and covered by new regression tests, but still impacts rendering correctness.Overview
Fixes
putImageDatain deferred rendering by routing writes throughPageRecorder.put_pixels()so pixel updates become visible togetImageData.Replaces the previous dirty-rect pixel write path with a new
skiac_canvas_put_image_dataimplementation that draws viadrawImageRectusingkSrcblend mode (pixel replacement) so operations are recordable bySkPictureRecorderand ignore clip/transform as required.Adds regression tests for #1204 covering basic
putImageDataand dirty-rect behavior.Written by Cursor Bugbot for commit f21d664. This will update automatically on new commits. Configure here.