ShaderLab: defining a Shader object

To define a Shader object in ShaderLab, use a Shader block. This page contains information on using Shader blocks.

For information on how a Shader object works, and the relationship between Shader objects, SubShaders and Passes, see Shader objects introduction.

Overview

A Shader object is a Unity-specific concept; it is a wrapper for shader programs and other information. It lets you define multiple shader programs in the same file, and tell Unity how to use them.

A Shader object has a nested structure; it organizes information into structures called SubShaders and Passes.

Render pipeline compatibility

Using the Shader block

Inside the Shader block, you can:

• Define material properties, using the Properties block. See ShaderLab: defining material properties.
• Define one or more SubShaders, using the SubShader block. See ShaderLab: defining a SubShader.
• Assign a custom editor, which determines how the shader asset appears in the Unity Editor. Optionally, you can assign different custom editors for different render pipelines. See ShaderLab: assigning custom editors.
• Assign a fallback Shader object, using the Fallback block. See ShaderLab: assigning a fallback.

Legacy shader names

Prior to Unity 5.0, some of the functionality of a shader was determined by its path and name. This is still how Unity’s Legacy Shaders work. Changing the name of these shaders can affect their functionality.

Examples

This example code demonstrates the basic syntax and structure of a Shader object. The example Shader object has a single SubShader that contains a single pass. It defines Material properties, a CustomEditor, and a Fallback.

Shader "Examples/ShaderSyntax"
{
    CustomEditor = "ExampleCustomEditor"

    Properties
    {
        // Material property declarations go here
    }
    SubShader
    {
        // The code that defines the rest of the SubShader goes here

        Pass
        {
           // The code that defines the Pass goes here
        }
    }

    Fallback "ExampleFallbackShader"
}

For example custom shaders that are compatible with different render pipelines, see Example custom shaders