perf(webgl): drop unused stencil buffer from context attributes#117
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No code path uses the stencil buffer (no stencilFunc/stencilOp/STENCIL_TEST; clipping is scissor-based and clear() only touches COLOR_BUFFER_BIT), but requesting it costs tile memory bandwidth on every flush on tile-based GPUs (Mali 400-class targets). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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What
Change
stencil: truetostencil: falseincreateWebGLContext(src/utils.ts). One-line change.Why
A repo-wide search shows nothing uses the stencil buffer: no
stencilFunc/stencilOp/stencilMask/STENCIL_TESTanywhere, clipping is scissor-based,WebGlContextWrapper.clear()only clearsCOLOR_BUFFER_BIT, and the RTT framebuffer (WebGlCtxRenderTexture) attaches onlyCOLOR_ATTACHMENT0with no stencil renderbuffer.Per the tile-based GPU rules in CLAUDE.md, every enabled buffer costs tile memory bandwidth on every flush on Mali 400-class targets — so an unused stencil buffer is pure waste.
Verification
stencil: truein utils.ts was the only stencil reference in the repo (src/, exports/, examples/)pnpm test: 267/267 unit tests pass🤖 Generated with Claude Code