Version: 2020.1
ShaderLab: SubShader LOD value
Debugging DirectX 11/12 shaders with Visual Studio

Using texture arrays in shaders

Similar to regular 2D textures (Texture2D class, sampler2D in shaders), cube maps (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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class, samplerCUBE in shaders), and 3D textures (Texture3D class, sampler3D in shaders), Unity also supports 2D texture arrays.

Since texture arrays do not work on all platforms, shadersA 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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need to use an appropriate compilation target or feature requirement to access them. The minimum shader model compilation target that supports texture arrays is 3.5, and the feature name is 2darray.

Use these macros to declare and sample texture arrays:

  • UNITY_DECLARE_TEX2DARRAY(name) declares a texture array sampler variable inside HLSL code.
  • UNITY_SAMPLE_TEX2DARRAY(name,uv) samples a texture array with a float3 UV; the z component of the coordinate is an array element index.
  • UNITY_SAMPLE_TEX2DARRAY_LOD(name,uv,lod) samples a texture array with an explicit mipmap level.


The following shader example samples a texture array using object space vertex positions as coordinates:

Shader "Example/Sample2DArrayTexture"
        _MyArr ("Tex", 2DArray) = "" {}
        _SliceRange ("Slices", Range(0,16)) = 6
        _UVScale ("UVScale", Float) = 1.0
            #pragma vertex vert
            #pragma fragment frag
            // texture arrays are not available everywhere,
            // only compile shader on platforms where they are
            #pragma require 2darray
            #include "UnityCG.cginc"

            struct v2f
                float3 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;

            float _SliceRange;
            float _UVScale;

            v2f vert (float4 vertex : POSITION)
                v2f o;
                o.vertex = mul(UNITY_MATRIX_MVP, vertex);
                o.uv.xy = (vertex.xy + 0.5) * _UVScale;
                o.uv.z = (vertex.z + 0.5) * _SliceRange;
                return o;

            half4 frag (v2f i) : SV_Target
                return UNITY_SAMPLE_TEX2DARRAY(_MyArr, i.uv);

See Also

  • 2018–03–20 Page amended
  • Shader #pragma directives added in Unity 2018.1
ShaderLab: SubShader LOD value
Debugging DirectX 11/12 shaders with Visual Studio