ShaderLab: assigning a LOD value to a SubShader

This page contains information on using a LOD block in your ShaderLab code to assign a LOD (level of detail) value to a SubShader.

개요

You can assign a LOD value to a SubShader. This value indicates how computationally demanding it is.

At runtime, you can set the shader LOD value for a single Shader object, or for all Shader objects. Unity then prioritises SubShaders that have a lower LOD value. For information on how Unity chooses when to use SubShaders, see Shader objects: Order of operations during rendering.

Note: Although this technique is named after the LOD feature for rendering meshes, there are important differences: shader LOD does not relate to distance from the Camera, and Unity does not calculate shader LOD automatically. You must set the maximum shader LOD manually.

개요

Use this technique to fine-tune shader performance on different hardware. This is useful when a SubShader is theoretically supported by a user’s hardware, but the hardware is not capable of running it well.

렌더 파이프라인 호환성

Feature name	빌트인 렌더 파이프라인	유니버설 렌더 파이프라인(URP)	고해상도 렌더 파이프라인(HDRP)	Custom SRP
ShaderLab: SubShader LOD block	지원	지원	지원	지원

Using the LOD block

In ShaderLab, you assign a LOD value to a SubShader by placing a LOD block inside a SubShader block.

Signature	기능
LOD [value]	Assigns the given LOD value to the SubShader.

Note: Inside your Shader block, you must put your SubShaders in descending LOD order. For example, if you have SubShaders with LOD values of 200, 100, and 500, you must put the SubShader with the LOD value of 500 first, followed by the one with a LOD value of 200, followed by the one with a LOD value of 100. This is because Unity selects the first valid SubShader it finds, so if it finds one with a lower LOD first it will always use that.

Using the SubShader LOD value with C# code

To set the shader LOD for a given Shader object, you can use Shader.maximumLOD. To set the shader LOD for all Shader objects, you can use Shader.globalMaximumLOD. By default, there is no maximum LOD.

Code examples

This example code creates a Shader object that contains two SubShaders: one with a LOD value of 200, and one with a value of 100. The SubShaders are in descending order of LOD value.

Shader "Examples/ExampleLOD"
{
    SubShader
    {
        LOD 200

        Pass
        {                
              // The rest of the code that defines the Pass goes here.
        }
    }

    SubShader
    {
        LOD 100

        Pass
        {                
              // The rest of the code that defines the Pass goes here.
        }
    }
}

LOD values for Unity’s built-in shaders

In the Built-in Render Pipeline, Unity’s built-in shaders have the following LOD values:

LOD value	Shader name
100	Unlit/Texture Unlit/Color Unlit/Transparent Unlit/Transparent Cutout
300	Standard Standard (Specular Setup) Autodesk Interactive

레거시 셰이더용 LOD 값

In the Built-in Render Pipeline, Unity’s built-in legacy shaders have the following LOD values:

LOD value	Shader name
100	VertexLit
150	Decal Reflective VertexLit
200	디퓨즈
250	Diffuse Detail Reflective Bumped Unlit Reflective Bumped VertexLit
300	Bumped Specular
400	범프 스페큘러
500	Parallax
600	Parallax Specular