Fix WebGPU staging buffer error in non-unified GSplat sorter#8499
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mvaligursky merged 1 commit intomainfrom Mar 4, 2026
Merged
Fix WebGPU staging buffer error in non-unified GSplat sorter#8499mvaligursky merged 1 commit intomainfrom
mvaligursky merged 1 commit intomainfrom
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…GSplat path The GSplatSorter uploaded sort results directly from the web worker message callback, which could fire multiple times between GPU submits. When two results arrived before the command buffer was submitted, the staging buffer from the first upload was mapped while still referenced by the unsubmitted encoder, causing a WebGPU validation error. Defer sort result uploads to GSplatInstance.update() via a pendingSorted field (matching the unified sorter pattern). Only the latest result is kept, avoiding both the validation error and redundant GPU uploads. Also adds a submitVersion counter to WebgpuGraphicsDevice and a diagnostic assert in WebgpuUploadStream to catch future violations of the one-upload- per-submit constraint. Made-with: Cursor
slimbuck
approved these changes
Mar 4, 2026
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Summary
GSplatSorter(non-unified path,unified=false) uploaded sort results directly from the web worker message callback. When multiple worker results arrived between GPU submits, the staging buffer from the first upload was mapped while still referenced by the unsubmitted command encoder, causing a WebGPU validation error:"buffer used in submit while mapped".GSplatInstance.update()via apendingSortedfield, matching the pattern used by the unified sorter (GSplatUnifiedSorter). Only the latest result is kept, avoiding both the validation error and redundant GPU uploads on both WebGL and WebGPU.submitVersioncounter toWebgpuGraphicsDeviceand a diagnostic assert inWebgpuUploadStreamto catch future violations of the one-upload-per-submit constraint.