R3f Shaders

For when you need to write custom GLSL shaders in React Three Fiber instead of using built-in materials. Covers the shaderMaterial helper from drei, which wraps your vertex and fragment shaders with uniform declarations, plus patterns for raw THREE.ShaderMaterial if you want full control. Good reference for uniform types, varyings, and updating shader values in useFrame. The HMR setup with the key prop is genuinely useful during development since you can edit shaders and see changes instantly. Most helpful when you're doing custom visual effects, vertex displacement, or anything where MeshStandardMaterial won't cut it.