UniformsGroup: Pool per-uniform update-range objects.#33427
Merged
Mugen87 merged 2 commits intomrdoob:devfrom Apr 21, 2026
Merged
UniformsGroup: Pool per-uniform update-range objects.#33427Mugen87 merged 2 commits intomrdoob:devfrom
Mugen87 merged 2 commits intomrdoob:devfrom
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`addUniformUpdateRange` allocated a fresh `{start, count}` object every
frame, for every uniform whose value changed. On an animated scene with
dozens of per-object uniforms this was hundreds of allocations per
frame — the single largest remaining source of sampled-heap traffic
after the earlier backend fixes.
Keep the range objects in `_updateRangeCache` across frames; mark each
as `added: false` on `clearUpdateRanges()` so the next frame pushes the
same cached object back onto `updateRanges` instead of allocating a
new one.
Measured on webgpu_backdrop_water (Inspector stripped, 10 s, 1 KB
sampling, 3-run average):
total sampled heap 97.0 KB → 66.5 KB (-31.5%)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
📦 Bundle sizeFull ESM build, minified and gzipped.
🌳 Bundle size after tree-shakingMinimal build including a renderer, camera, empty scene, and dependencies.
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This was referenced Apr 20, 2026
Mugen87
reviewed
Apr 20, 2026
Reviewer feedback: the `added` flag attached to each cached range object
muddles the shape that `Buffer._updateRanges` and its downstream
consumers (WebGL/WebGPU upload paths) expect to see — a clean
`{start, count}`.
Move the "already pushed this cycle" membership into a separate
`_addedIndices` Set on the instance. The cached range objects stay a
pure `{start, count}` pair, and `start`/`count` are re-assigned from the
uniform on every `addUniformUpdateRange` call (rather than only on cache
miss), so any in-place mutation downstream — e.g. WebGL's sort/merge of
ranges — cannot leak stale state into the next frame. `clearUpdateRanges`
simplifies to clearing the Set and delegating to `super`.
No behavioral change for consumers; same pooling, cleaner contract.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Mugen87
approved these changes
Apr 21, 2026
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Related: #33419
Description
UniformsGroup.addUniformUpdateRangeallocated a fresh{ start, count }object every frame for every uniform whose value changed. Keep the range objects in_updateRangeCacheacross frames; mark each asadded: falseinclearUpdateRanges()so the next frame pushes the same cached object ontoupdateRangesrather than allocating a new one.Before / after —
webgpu_backdrop_water, 10 s, 1 KB sampling, Inspector stripped, 3-run averageupdateNumber @ UniformsGroup.js:267(caller){ start, count }allocations per frameThis contribution is funded by Spawn