Compute shaders are shaderA program that runs on the GPU. More info
See in Glossary programs that run on the GPU, outside of the normal rendering pipeline.
They can be used for massively parallel GPGPU algorithms, or to accelerate parts of game rendering. In order to efficiently use them, an in-depth knowledge of GPU architectures and parallel algorithms is often needed; as well as knowledge of DirectCompute, OpenGL Compute, CUDA, or OpenCL.
Compute shaders in Unity closely match DirectX 11 DirectCompute technology. Platforms where compute shaders work:
Windows and Windows Store, with a DirectX 11 or DirectX 12 graphics API and Shader Model 5.0 GPU
macOS and iOS using Metal graphics API
Android, Linux and Windows platforms with Vulkan API
Modern OpenGL platforms (OpenGL 4.3 on Linux or Windows; OpenGL ES 3.1 on Android). Note that Mac OS X does not support OpenGL 4.3
Modern consoles
As with regular shaders, Unity is capable of translating compute shaders from HLSL to other shader languages. Therefore, for the easiest cross-platform builds, you should write compute shaders in HLSL. However, there are some factors that need to be considered when doing this.