Fix WebGL readTextureAsync allocating too much memory for outputData#8472
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willeastcott
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Pull request overview
This pull request fixes a memory over-allocation bug in WebGL's readTextureAsync method. The method was incorrectly passing byte sizes directly to typed array constructors, which interpret the argument as element count, resulting in over-allocation by factors of 2× to 4× depending on the pixel format.
Changes:
- Fixed
readTextureAsyncto divide byte size byBYTES_PER_ELEMENTwhen allocating typed arrays - Improved code readability by extracting
ArrayTypeto a variable
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mvaligursky
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Feb 23, 2026
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looks good. glad webgpu is unaffected.
mvaligursky
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Feb 24, 2026
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readTextureAsyncpasses the result ofTextureUtils.calcLevelGpuSize()(which returns bytes) directly as the element count to a typed array constructor. For multi-byte element types this over-allocates by a factor ofBYTES_PER_ELEMENT(e.g. 4× forFloat32Array/Uint32Arrayformats, 2× forUint16Arrayformats).The fix divides the byte size by
ArrayType.BYTES_PER_ELEMENTto produce the correct element count.