Version: 2020.2
ShaderLab Syntax
ShaderLab: SubShader

ShaderLab: Properties

Shaders can define a list of parameters to be set by artists in Unity’s material inspector. The Properties block in the shader file defines them.

Syntax

Properties

Properties { Property [Property ...] }

Defines the property block. Inside braces multiple properties are defined as follows.

Numbers and Sliders

name ("display name", Range (min, max)) = number
name ("display name", Float) = number
name ("display name", Int) = number

These all defines a number (scalar) property with a default value. The Range form makes it be displayed as a slider between min and max ranges.

Colors and Vectors

name ("display name", Color) = (number,number,number,number)
name ("display name", Vector) = (number,number,number,number)

Defines a color property with default value of given RGBA components, or a 4D vector property with a default value. Color properties have a color picker shown for them, and are adjusted as needed depending on the color space (see Properties in Shader Programs). Vector properties are displayed as four number fields.

Textures

name ("display name", 2D) = "defaulttexture" {}
name ("display name", Cube) = "defaulttexture" {}
name ("display name", 3D) = "defaulttexture" {}

Defines a 2D Texture, cubemapA collection of six square textures that can represent the reflections in an environment or the skybox drawn behind your geometry. The six squares form the faces of an imaginary cube that surrounds an object; each face represents the view along the directions of the world axes (up, down, left, right, forward and back). More info
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or 3D (volume) property respectively.

Details

Each property inside the shaderA small script that contains the mathematical calculations and algorithms for calculating the Color of each pixel rendered, based on the lighting input and the Material configuration. More info
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is referenced by name (in Unity, it’s common to start shader property names with underscore). The property will show up in material inspectorA Unity window that displays information about the currently selected GameObject, asset or project settings, allowing you to inspect and edit the values. More info
See in Glossary
as display name. For each property a default value is given after equals sign:

  • For Range and Float properties it’s just a single number, for example “13.37”.
  • For Color and Vector properties it’s four numbers in parentheses, for example “(1,0.5,0.2,1)”.
  • For 2D Textures, the default value is either an empty string, or one of the built-in default Textures: “white” (RGBA: 1,1,1,1), “black” (RGBA: 0,0,0,0), “gray” (RGBA: 0.5,0.5,0.5,0.5), “bump” (RGBA: 0.5,0.5,1,0.5) or “red” (RGBA: 1,0,0,0).
  • For non–2D Textures (Cube, 3D, 2DArray) the default value is an empty string. When a Material does not have a Cubemap/3D/Array Texture assigned, a gray one (RGBA: 0.5,0.5,0.5,0.5) is used.

Later on in the shader’s fixed function parts, property values can be accessed using property name in square brackets: [name]. For example, you could make blending mode be driven by a material property by declaring two integer properties (say “SrcBlend“ and ”DstBlend”), and later on make Blend Command use them: Blend [_SrcBlend] [_DstBlend].

Shader parameters that are in the Properties block are serialized as MaterialAn asset that defines how a surface should be rendered, by including references to the Textures it uses, tiling information, Color tints and more. The available options for a Material depend on which Shader the Material is using. More info
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data. Shader programs can actually have more parameters (like matrices, vectors and floats) that are set on the material from code at runtime, but if they are not part of the Properties block then their values will not be saved. This is mostly useful for values that are completely script code-driven (using Material.SetFloat and similar functions).

Property attributes and drawers

In front of any property, optional attributes in square brackets can be specified. These are either attributes recognized by Unity, or they can indicate your own MaterialPropertyDrawer classes to control how they should be rendered in the material inspector. Attributes recognized by Unity:

  • [HideInInspector] - does not show the property value in the Material inspector.
  • [NoScaleOffset] - material inspector will not show Texture tiling/offset fields for Texture properties with this attribute.
  • [Normal] - indicates that a Texture property expects a normal-map.
  • [HDR] - indicates that a Texture property expects a high-dynamic range (HDR) Texture.
  • [Gamma] - indicates that a float/vector property is specified as sRGB value in the UI(User Interface) Allows a user to interact with your application. More info
    See in Glossary
    (just like colors are), and possibly needs conversion according to color space used. See Properties in Shader Programs.
  • [PerRendererData] - indicates that a property will be coming from per-renderer data in the form of a MaterialPropertyBlock. Material inspector shows these properties as read-only.
  • [MainTexture] - indicates that a property is the main texture for a Material. By default, Unity considers a texture with the property name name _MainTex as the main texture. Use this attribute if your texture has a different property name, but you want Unity to consider it the main texture. If you use this attribute more than once, Unity uses the first property and ignores subsequent ones. When the main texture is set using the [MainTexture] attribute, it is not visible in the Inspector in Debug mode. When the main texture is set using the [MainTexture] attribute, it is not visible in the Game view when you use the texture streaming debugging view mode or a custom debug tool.
  • [MainColor] - indicates that a property is the main color for a Material. By default, Unity considers a color with the property name name _Color as the main color. Use this attribute if your color has a different property name, but you want Unity to consider it the main color. If you use this attribute more than once, Unity uses the first property and ignores subsequent ones.

Example

// properties for a water shader
Properties
{
    _WaveScale ("Wave scale", Range (0.02,0.15)) = 0.07 // sliders
    _ReflDistort ("Reflection distort", Range (0,1.5)) = 0.5
    _RefrDistort ("Refraction distort", Range (0,1.5)) = 0.4
    _RefrColor ("Refraction color", Color) = (.34, .85, .92, 1) // color
    _ReflectionTex ("Environment Reflection", 2D) = "" {} // textures
    _RefractionTex ("Environment Refraction", 2D) = "" {}
    _Fresnel ("Fresnel (A) ", 2D) = "" {}
    _BumpMap ("Bumpmap (RGB) ", 2D) = "" {}
}

See Also

  • [MainTexture and MainColour attributes] added in 2019.3 NewIn20193
ShaderLab Syntax
ShaderLab: SubShader