This patch adds initial support for compute shaders and SSBOs to
the vulkan backend. As the development is oriented to the test-
cases we have the implementation is limited to what is used there.
It has been validated that with this patch 2 test cases are running
as expected
- `GPUVulkanTest.gpu_shader_compute_ssbo`
- `GPUVulkanTest.gpu_storage_buffer_create_update_read`
This patch includes:
- Allocating VkBuffer on device.
- Uploading data from CPU to VkBuffer.
- Binding VkBuffer as SSBO to a compute shader.
- Execute compute shader and altering VkBuffer.
- Download the VkBuffer to CPU ram.
- Validate that it worked.
GHOST API has been changed as the original design was created before
we even had support for compute shaders in blender. The function `GHOST_getVulkanBackbuffer` has been separated to retrieve the command
buffer without a backbuffer (`GHOST_getVulkanCommandBuffer`). In order
to do correct command buffer processing we needed access to the queue
owned by GHOST. This is returned as part of the `GHOST_getVulkanHandles`
function.
Jeroen Bakker