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BlendOp command in ShaderLab reference

Reference for the BlendOp command in ShaderLab.
Read time 3 minutesLast updated a month ago
Important
The Built-In Render Pipeline is deprecated and will be made obsolete in a future release.
It remains supported, including bug fixes and maintenance, through the full Unity 6.7 LTS lifecycle.
For more information on migration, refer to Migrating from the Built-In Render Pipeline to the Universal Render Pipeline and Render pipeline feature comparison.
Specifies the blending operation used by the Blend command. For this command to have any effect, there must also be a Blend command in the same Pass block (if this command is in a Pass block) or SubShader block (if this command is in a SubShader block).
Not all blending operations are supported on all devices, and support depends on both the graphics API and the hardware. Different graphics APIs handle unsupported blending operations differently: GL skips unsupported operations, and Vulkan and Metal fall back to Add operations.

Render pipeline compatibility

Feature name

Universal Render Pipeline (URP)

High Definition Render Pipeline (HDRP)

Custom SRP

Built-in Render Pipeline

BlendOpYesYesYesYes

Syntax

This command makes a change to the render state. Use it in a 
Pass
block to set the render state for that Pass, or use it in a 
SubShader
block to set the render state for all Passes in that SubShader.

Signature

Example syntax

Function

BlendOp <operation>
BlendOp Sub
Sets the blending operation used by the Blend command.

Parameters

Parameter

Value

Function

operation
Add
Add source and destination together.
Sub
Subtract destination from source.
RevSub
Subtract source from destination.
Min
Use the smaller of source and destination.
Max
Use the larger of source and destination.
LogicalClear
Logical operation: 
Clear (0)
(1)
LogicalSet
Logical operation: 
Set (1)
(1)
LogicalCopy
Logical operation: 
Copy (s)
(1)
LogicalCopyInverted
Logical operation: 
Copy inverted (!s)
2
LogicalNoop
Logical operation: 
Noop (d)
(1)
LogicalInvert
Logical operation: 
Invert (!d)
(1)
LogicalAnd
Logical operation: 
And (s & d)
(1)
LogicalNand
Logical operation: 
Nand !(s & d)
(1)
LogicalOr
Logical operation: `Or (s
LogicalNor
Logical operation: `Nor !(s
LogicalXor
Logical operation: 
Xor (s ^ d)
(1)
LogicalEquiv
Logical operation: 
Equivalence !(s ^ d)
(1)
LogicalAndReverse
Logical operation: 
Reverse And (s & !d)
(1)
LogicalAndInverted
Logical operation: 
Inverted And (!s & d)
(1)
LogicalOrReverse
Logical operation: `Reverse Or (s
LogicalOrInverted
Logical operation: `Inverted Or (!s
Multiply
Advanced OpenGL blending operation: 
Multiply
(2)
Screen
Advanced OpenGL blending operation: 
Screen
(2)
Overlay
Advanced OpenGL blending operation: 
Overlay
(2)
Darken
Advanced OpenGL blending operation: 
Darken
(2)
Lighten
Advanced OpenGL blending operation: 
Lighten
(2)
ColorDodge
Advanced OpenGL blending operation: 
ColorDodge
(2)
ColorBurn
Advanced OpenGL blending operation: 
ColorBurn
(2)
HardLight
Advanced OpenGL blending operation: 
HardLight
(2)
SoftLight
Advanced OpenGL blending operation: 
SoftLight
(2)
Difference
Advanced OpenGL blending operation: 
Difference
(2)
Exclusion
Advanced OpenGL blending operation: 
Exclusion
(2)
HSLHue
Advanced OpenGL blending operation: 
HSLHue
(2)
HSLSaturation
Advanced OpenGL blending operation: 
HSLSaturation
(2)
HSLColor
Advanced OpenGL blending operation: 
HSLColor
(2)
HSLLuminosity
Advanced OpenGL blending operation: 
HSLLuminosity
(2)
Notes:
  1. Logical operations require DX 11.1+ or Vulkan.
  2. Advanced OpenGL blending operations require 
    GLES3.1 AEP+
    , 
    GL_KHR_blend_equation_advanced
    , or 
    GL_NV_blend_equation_advanced
    . They can only be used with standard RGBA blending; they are not compatible with separate RGB and alpha blending.

Examples

Shader "Examples/CommandExample"{    SubShader    {         // The rest of the code that defines the SubShader goes here.        Pass        {                 // Enable subtractive blending for this Pass             Blend SrcAlpha One             BlendOp RevSub                          // The rest of the code that defines the Pass goes here.        }    }}
This example code demonstrates the syntax for using this command in a SubShader block.
Shader "Examples/CommandExample"{    SubShader    {         // Enable subtractive blending for this SubShader         Blend SrcAlpha One         BlendOp RevSub         // The rest of the code that defines the SubShader goes here.                Pass        {                  // The rest of the code that defines the Pass goes here.        }    }}

Additional resources