Understanding task and mesh shaders

Before we begin, we should mention that mesh shaders can be used without task shaders. If, for instance, you wanted to perform culling or some other pre-processing step on the meshlets on the CPU, you are free to do so.

Also, note that task and mesh shaders replace vertex shaders in the graphics pipeline. The output of mesh shaders is going to be consumed by the fragment shader directly.

The following diagram illustrates the differences between the traditional geometry pipeline and the mesh shader pipeline:

Figure 6.4 – The difference between traditional and mesh pipeline

In this section, we are going to provide an overview of how task and mesh shaders work and then use this information to implement back-face and frustum culling using task shaders.

Both task and mesh shaders use the same execution model of compute shaders, with some minor changes. The output of task shaders is consumed directly by a mesh...