@fourjs/materials

Materials and shading. Part of fourJS.

Implements the MVP tier of §57–60 in docs/SPECIFICATION.md; shipped in Phases 3 and 3a.

What's here

• Material — the §57 base: the seven shared members (stencil among them, R-7) every class below extends.
• UnlitMaterial — flat-color material (ColorRGBA, re-exported from @fourjs/math); color is read per draw, so in-place tuple animation works.
• SpriteMaterial — textured-quad material over the SpriteTexture contract (§55/§77 MVP tier), used by @fourjs/render's Sprite.
• LitMaterial (§68, 2026-08-04) — the Lambert diffuse tier: color × (ambient + lightColor · max(N·−L, 0)).
• StandardMaterial (§59, 2026-08-08) — glTF-compatible metallic-roughness: baseColor, metalness, roughness, emissive, and the map / metalRoughnessMap / emissiveMap / normalMap / occlusionMap slots. On WebGL 2 it draws behind registerStandardPipeline(); without that call the renderer skips those draws and says so (§59).
• StencilState (§57, 2026-08-21) — the per-material stencil packet, with MAX_STENCIL_VALUE.
• The node-material shader system (§60, RFC 0001, 2026-08-28) — ShaderGraphBuilder / ShaderExpression / ShaderFunction / ShaderOperatorRegistry build the IR, analyzeShaderGraph + freezeShaderGraph + forEachShaderNodeReference validate and walk it, NodeMaterialBuilder compiles it into a NodeMaterial, and ShaderVariantSet + createShaderSourceMap carry the variants. Bounds are MAX_SHADER_GRAPH_NODES / MAX_SHADER_GRAPH_TEXTURES; the emitters register from the backends (registerNodeMaterialPipeline(), registerWebgpuNodeMaterialPipeline()).
• liveMaterialCount (§83) — the material half of the resource-accounting pair.

Corrected 2026-09-19 (dogfood cycle 9): this section listed only UnlitMaterial and SpriteMaterial, and the section below called StandardMaterial, lighting and the node-material system "staged". All three had shipped — lighting on 2026-08-04, StandardMaterial on 2026-08-08, the node-material system on 2026-08-28. Measured from a consumer seat against the staged, packed, installed packages: the fourJS/materials subpath resolves 26 exports, and an UnlitMaterial, a LitMaterial and a StandardMaterial drew 20,128, 14,923 and 6,636 pixels in one WebGL 2 frame in Chrome. docs/guides/materials-and-render-graph.md had already been corrected; this file had not.

Staged / not yet implemented

• PhysicalMaterial and §59's physical extensions (clearcoat, transmission, sheen). ShaderMaterial is permanently unshipped (spec rev 1.11).
• §55 texture frame regions — sprites currently map whole textures; the paints/fills/strokes model of §58.

Unit tests are colocated in tests/ per §92.

Workspace name @fourjs/materials; publishes as @danielsimonjr/fourjs-materials.