Authors Three.js custom shaders: ShaderMaterial vs RawShaderMaterial, GLSL uniforms/varyings, vertex deformation, fragment effects, onBeforeCompile hooks, and TSL for WebGPU. Use when writing or migrating Three.js shaders or extending built-in materials. Not for scene/camera/renderer scaffold (threejs-fundamentals) or picking a specialist via threejs-skill-router.
