ShaderMaterial class

A material rendered with custom shaders. A shader is a small program written in GLSL that runs on the GPU. You may want to use a custom shader if you need to:

• implement an effect not included with any of the built-in [materials]
• combine many objects into a single [BufferGeometry] in order to improve performance

There are the following notes to bear in mind when using a `ShaderMaterial`:

• A `ShaderMaterial` will only be rendered properly by [WebGLRenderer], since the GLSL code in the [link:https://en.wikipedia.org/wiki/Shader#Vertex_shaders vertexShader] and [link:https://en.wikipedia.org/wiki/Shader#Pixel_shaders fragmentShader] properties must be compiled and run on the GPU using WebGL.
• As of THREE r72, directly assigning attributes in a ShaderMaterial is no longer supported. A [BufferGeometry] instance must be used instead, using [BufferAttribute] instances to define custom attributes.
• As of THREE r77, [WebGLRenderTarget] or [WebGLCubeRenderTarget] instances are no longer supposed to be used as uniforms. Their [Texture texture] property must be used instead.
• Built in attributes and uniforms are passed to the shaders along with your code. If you don't want the [WebGLProgram] to add anything to your shader code, you can use [RawShaderMaterial] instead of this class.
• You can use the directive #pragma unroll_loop_start and #pragma unroll_loop_end in order to unroll a `for` loop in GLSL by the shader preprocessor. The directive has to be placed right above the loop. The loop formatting has to correspond to a defined standard.
  • The loop has to be [link:https://en.wikipedia.org/wiki/Normalized_loop normalized].
  • The loop variable has to be *i*.
  • The value `UNROLLED_LOOP_INDEX` will be replaced with the explicitly value of *i* for the given iteration and can be used in preprocessor statements.
  #pragma unroll_loop_start for ( int i = 0; i < 10; i ++ ) { // ... } #pragma unroll_loop_end