3D Wood Lighting Scorecard

Wood only looks like wood under one directional key raking across a dark room, so the grain, the shadow seam and the light shafts are lit by the same window, tone-mapped once at the end, and each is measured on the finished frame instead of judged by mood.

Verified stack: Three.js r169 (unpkg), WebGL2, GLSL patched into MeshPhysicalMaterial.onBeforeCompile, a half-float MSAA target and a hand-written ACES pass. The demo is demo.html; the numbers are references/.

Boundaries. This is the lighting-and-material layer for one lit interior. For sun shafts that must be cut by real trees and rooflines use 3d-sky-rays (screen-space occlusion); here the shafts are authored planes. For scanned or painted PBR maps, texel budgets and delivery use 3d-high-resolution-textures; here the wood is procedural from one shared 1024 noise field. For a bright rim on dark metal use 3d-specular-rim-glow; for glass use the studio-box ladder, not this. For the scoring habit alone use workflow-score-to-target; this skill supplies the wood rubric and the machine that measures it.

Extracted from Kibori (木彫), a scroll-driven WebGL woodworking page: its woodMat, buildEnvironment, key rig, shaft planes, dust and final pass are ported, with the window moved to where the shafts need it.

Build order

1. Renderer: NoToneMapping, LinearSRGBColorSpace, HalfFloatType target with samples: 4, autoClear = false. Draw everything, additive shafts and dust included, into that target. Tone-map once in a last full-screen pass.
2. One window. Put the emissive paper, the key light's direction, the shaft planes, and the window card in the PMREM environment on the same line. Nothing else.
3. Key DirectionalLight 0xfff2df, intensity 2.0, 4096 shadow map (2048 under 820 px), normalBias 0.0045 (0.0085 at 2048), bias -0.00025, shadowMap.autoUpdate = false for a static room. Let a real wall with a real opening cast: the pool of light on the bench is then the window's shape.
4. Fill 0xaec7df 0.60-0.76 from the camera side, rim 0xffdeb4 0.72 from behind, hemisphere 0xb5c5d7 / 0x35281c 0.19. These only keep the shaded flank alive; they are not the look.
5. Wood: MeshPhysicalMaterial ior 1.43, specularIntensity 0.72, roughness clamp(base * W.rough, 0.35, 1), procedural albedo/roughness/bump from one periodic noise field baked once (1024x1024 RGBA8, 64 cells, three octaves, mipmapped, repeat).
6. Shafts, then dust, then the last pass, then run references/scorecard.mjs.