| index | Index of the random write target in the shader. |
| uav | RenderTexture/ComputeBuffer to set as write target. |
Set random write target for Shader Model 5.0 level pixel shaders.
Shader Model 5.0 level pixel shaders can write into arbitrary locations of some textures and buffers, called "unordered access views" (UAV) in DirectX 11. These "random write" targets are set similarly to how multiple render targets are set. You can either use a RenderTexture with enableRandomWrite flag set, or a ComputeBuffer as target.
The UAV indexing varies a bit between different platforms. On DX11 the first valid UAV index is the number of active render targets. So the common case of single render target the UAV indexing will start from 1. OpenGL ES 3.1 matches this behaviour when using translated HLSL shaders. However, with hand-written GLSL shaders the indexes will match the bindings. On PS4 the indexing starts always from 1 to match the most common case.
The targets stay set until you manually clear them with ClearRandomWriteTargets.
See Also: RenderTexture.enableRandomWrite, ComputeBuffer, DirectX 11.