test(render): benchmark the perspective lightmapped fill (hot path) - #19
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Adds a benchmark for FillPerspectiveLightmappedPolygon -- the per-pixel perspective-correct textured + lightmapped rasterizer the software renderer spends most of a world frame in. It fills a large (~250k px), depth-tilted, lightmapped quad so the 1/z subdivision, texture wrap, and bilinear lightmap sampler all run for real (0 allocs). Baseline on this machine: ~1.0 ms/quad (~4 ns/px). Establishes a fixed reference for the renderer perf work: a fixed-point rewrite of the inner bilinear was tried and MEASURED as a 16% regression (math.Floor is a ROUNDSD intrinsic and native float64 is already fast), so the lever is architectural (overdraw reduction / surface cache), not the per-pixel arithmetic. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Adds a benchmark for
FillPerspectiveLightmappedPolygon— the per-pixel perspective-correct textured + lightmapped rasterizer the software renderer spends most of a world frame in. It fills a large (~250k px), depth-tilted, lightmapped quad so the 1/z subdivision, texture wrap, and bilinear lightmap sampler all run for real (0 allocs).Baseline on this machine: ~1.0 ms/quad (~4 ns/px).
Establishes a fixed reference for the renderer perf work. A fixed-point rewrite of the inner bilinear was tried and measured as a 16% regression (
math.Floorcompiles to aROUNDSDintrinsic and native float64 is already fast), so the lever is architectural (overdraw reduction / surface cache), not the per-pixel arithmetic.🤖 Generated with Claude Code