Version: Unity 6.1 Alpha (6000.1)
Language : English
Name directive in ShaderLab reference
Shader code blocks in ShaderLab reference

Pass tags in ShaderLab reference

This page contains information on using a Tags block in your ShaderLabUnity’s language for defining the structure of Shader objects. More info
See in Glossary
code to assign tags to a Pass. It also contains information on using the LightMode tag.

For information on how a ShaderA program that runs on the GPU. More info
See in Glossary
object works, and the relationship between Shader objectsAn instance of the Shader class, a Shader object is container for shader programs and GPU instructions, and information that tells Unity how to use them. Use them with materials to determine the appearance of your scene. More info
See in Glossary
, SubShaders and Passes, see Shader object fundamentals.

Render pipeline compatibility

Feature name Universal Render PipelineA series of operations that take the contents of a Scene, and displays them on a screen. Unity lets you choose from pre-built render pipelines, or write your own. More info
See in Glossary
(URP)
High Definition Render Pipeline (HDRP) Custom SRP Built-in Render Pipeline
ShaderLab: Pass Tags block Yes Yes Yes Yes
ShaderLab: LightMode Pass tag Yes Yes Yes Yes

Syntax

Signature Function
Tags {"<name1>" = "<value1>" "<name2>" = "<value2>"} Applies the given tags to the Pass.

You can define as many tags as you like.

LightMode tag

Signature Function
“LightMode” = “[value]” Sets the LightMode value for this Pass.

Valid values for this tag depend on the render pipeline.

LightMode tag valid values

These are the valid values for the LightMode Pass tag in the Built-in Render Pipeline. For more information on the LightMode tag, see ShaderLab: using Pass tags.

Value Function
Always Always rendered; does not apply any lighting. This is the default value.
ForwardBase Used in Forward renderingA rendering path that renders each object in one or more passes, depending on lights that affect the object. Lights themselves are also treated differently by Forward Rendering, depending on their settings and intensity. More info
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; applies ambient, main directional light, vertex/SH lights and lightmapsA pre-rendered texture that contains the effects of light sources on static objects in the scene. Lightmaps are overlaid on top of scene geometry to create the effect of lighting. More info
See in Glossary
.
ForwardAdd Used in Forward rendering; applies additive per-pixel lights, one Pass per light.
Deferred Used in Deferred ShadingA rendering path in the Built-in Render Pipeline that places no limit on the number of Lights that can affect a GameObject. All Lights are evaluated per-pixel, which means that they all interact correctly with normal maps and so on. Additionally, all Lights can have cookies and shadows. More info
See in Glossary
; renders G-buffer.
ShadowCaster Renders object depth into the shadowmap or a depth texture.
MotionVectors Used to calculate per-object motion vectors.
Vertex Used in legacy Vertex Lit rendering when the object is not lightmapped; applies all vertex lights.
VertexLMRGBM Used in legacy Vertex Lit rendering when the object is lightmapped, and on platforms where the lightmap is RGBM encoded (PC & console).
VertexLM Used in legacy Vertex Lit rendering when the object is lightmapped, and on platforms where lightmap is double-LDR encoded (mobile platforms).
Meta This Pass is not used during regular rendering, only for lightmap baking or EnlightenA lighting system by Geomerics used in Unity for Enlighten Realtime Global Illumination. More info
See in Glossary
Realtime Global IlluminationA group of techniques that model both direct and indirect lighting to provide realistic lighting results.
See in Glossary
. For more information, see Lightmapping and shaders.

PassFlags tag

In the Built-in Render Pipeline, use the PassFlags Pass tag to specify what data Unity provides to the Pass.

Value Function
OnlyDirectional Valid only in the Built-in Render Pipeline, when the rendering path is set to Forward, in a Pass with a LightMode tag value of ForwardBase.

Unity provides only the main directional light and ambient/light probe data to this Pass. This means that data of non-important lights is not passed into vertex-light or spherical harmonics shader variables. See Forward rendering path for details.

Example

Shader "Examples/ExamplePassFlag"
{
    SubShader
    {
        Pass
        {    
              Tags { "LightMode" = "ForwardBase" "PassFlags" = "OnlyDirectional" }
            
              // The rest of the code that defines the Pass goes here.
        }
    }
}

RequireOptions tag

In the Built-in Render Pipeline, the RequireOptions Pass tag enables or disables a Pass based on project settingsA broad collection of settings which allow you to configure how Physics, Audio, Networking, Graphics, Input and many other areas of your project behave. More info
See in Glossary
.

Value Function
SoftVegetation Render this Pass only if QualitySettings-softVegetation is enabled.

Additional resources

Name directive in ShaderLab reference
Shader code blocks in ShaderLab reference