Reuse HLSL code

To tell the compiler to include existing High-Level ShaderA program that runs on the GPU. More info
See in Glossary Language (HLSL) code in another file or section, use the following methods:

• Include an HLSL file in another, using the standard HLSL #include directive.
• Duplicate HLSL in multiple places using the HLSLINCLUDE and ENDHLSL macros.
• Apply a #pragma directive to multiple HLSL files, using the Unity #include_with_pragmas directive.

Include an HLSL file in another

Unity supports the standard HLSL #include directive. For more information, refer to include directive in the Microsoft HLSL documentation.

Duplicate HLSL in multiple places

To duplicate HLSL code in all the sections of your code, for example to add the same variables in multiple Pass blocks, wrap the code you want to reuse in HLSLINCLUDE and ENDHLSL macros. Unity adds the code at the top of every HLSLPROGRAM block.

For example:

Shader "Examples/ExampleShader"
{
    HLSLINCLUDE
        // Add HLSL code you want to share across the file.
    ENDHLSL

    SubShader
    {
        Pass
        {                
              ...

              HLSLPROGRAM
                // Unity pastes the contents of the HLSLINCLUDE block here.
              ENDHLSL
        }

        Pass
        {                
              ...

              HLSLPROGRAM
                // Unity pastes the contents of the HLSLINCLUDE block here.
              ENDHLSL
        }

    }
}

Apply a pragma directive to multiple files

To apply a #pragma directive to multiple shader files, use the Unity #include_with_pragmas directive.

You can use this method to add an argument in multiple files, but toggle the arguments on and off by updating only one file. For example, you can create and toggle a debugging keyword that enables and disables conditional debugging code in multiple shaders.

1. Add a #pragma directive to a separate shader file. For example, create a one-line HLSL file with a pragma that enables shader debug symbols:

  #pragma enable_d3d11_debug_symbols

1. In each shader you want to include the directive in, add an #include_with_pragmas directive to include the file. For example:

  #include_with_pragmas "path-to-include-file"

Note: If a shader file uses #include to import a file that contains an #include_with_pragmas directive, Unity ignores the #pragma directives in the file the #include_with_pragmas directive references. Unity warns you about this in the console.

Additional resources

• ShaderLab: adding shader programs