In Unity, you write shader programs using the HLSL programming language.
This section of the manual includes information on using HLSL in a Unity-specific way. For general information on writing HLSL, see Microsoft’s HLSL documentation.
Note: Unity originally used the Cg language, hence the name of some of Unity’s keywords (CGPROGRAM
) and file extensions (.cginc
). Unity no longer uses Cg, but these names are still in use.
You place your HLSL code inside code blocks in your ShaderLab code. They usually look like this:
Pass {
// ... the usual pass state setup ...
HLSLPROGRAM
// compilation directives for this snippet, e.g.:
#pragma vertex vert
#pragma fragment frag
// the shader program itself
ENDHLSL
// ... the rest of pass ...
}
For more information on shader code blocks, see ShaderLab: adding shader programs.
HLSL has two syntaxes: a legacy DirectX 9-style syntax, and a more modern DirectX 10+ style syntax. The difference is mostly in how texture sampling functions work:
Unity provides shader libraries that contain preprocessor macros to help you manage these differences. For more information, see Built-in shader macros.