GPU: Compute Pipeline.

With the compute pipeline calculation can be offloaded to the GPU.
This patch only adds the framework for compute. So no changes for users at
this moment.

NOTE: As this is an OpenGL4.3 feature it must always have a fallback.

Use `GPU_compute_shader_support` to check if compute pipeline can be used.
Check `gpu_shader_compute*` test cases for usage.

This patch also adds support for shader storage buffer objects and device only
vertex/index buffers.

An alternative that had been discussed was adding this to the `GPUBatch`, this
was eventually not chosen as it would lead to more code when used as part of a
shading group. The idea is that we add an `eDRWCommandType` in the near
future.

Reviewed By: fclem

Differential Revision: https://developer.blender.org/D10913

1 files changed, 3 insertions, 0 deletions

diff --git a/source/blender/gpu/opengl/gl_state.hh b/source/blender/gpu/opengl/gl_state.hh
index 651c3c22afa..3b4b40b1d10 100644
--- a/source/blender/gpu/opengl/gl_state.hh
+++ b/source/blender/gpu/opengl/gl_state.hh
@@ -121,6 +121,9 @@ static inline GLbitfield to_gl(eGPUBarrier barrier_bits)
   if (barrier_bits & GPU_BARRIER_TEXTURE_FETCH) {
     barrier |= GL_TEXTURE_FETCH_BARRIER_BIT;
   }
+  if (barrier_bits & GPU_BARRIER_SHADER_STORAGE) {
+    barrier |= GL_SHADER_STORAGE_BARRIER_BIT;
+  }
   return barrier;
 }