Vulkan has a pluggable memory allocation feature, which allows internal
driver allocations to be done by the client application provided
allocator. Vulkan uses this for more client application allocations
done inside the driver, but can also do it for more internal oriented
allocations.
VK_ALLOCATION_CALLBACKS initializes allocation callbacks for host allocations.
The macro creates a local static variable with the name vk_allocation_callbacks
that can be passed to vulkan API functions that expect
const VkAllocationCallbacks *pAllocator.
When WITH_VULKAN_GUARDEDALLOC=Off the memory allocation implemented
in the vulkan device driver is used for both internal and application
oriented memory operations.
For now this would help during the development of Vulkan backend to
detect hidden memory leaks that are hidden inside the driver part
of the stack. In a later stage we need to measure the overhead and
if this should become the default behavior.
Pull Request #104434
Compile each static shader using shaderc to Spir-V binaries.
The main goal is to make sure that the GLSL created using ShaderCreateInfo and able to compile to Spir-V.
For the second stage a correct pipeline needs to be created and some shader would need more
adjustments (push constants size).
With this patch future changes to GLSL sources can already be checked against vulkan, without the
backend finished.
Mechanism has been tested using MacOS and MoltenVK. For other OS, we should finetune CMake
files to find the right location to shaderc.
```
************************************************************
*** Build Mon 12 Dec 2022 11:08:07 CET
************************************************************
Shader Test compilation result: 463 / 463 passed (skipped 118 for compatibility reasons)
OpenGL backend shader compilation succeeded.
Shader Test compilation result: 529 / 529 passed (skipped 52 for compatibility reasons)
Vulkan backend shader compilation succeeded.
```
Reviewed By: fclem
Maniphest Tasks: T102760
Differential Revision: https://developer.blender.org/D16610
This patch adds a placeholder for the vulkan backend.
When activated (`WITH_VULKAN_BACKEND=On` and `--gpu-backend vulkan`)
it might open a blender screen, but nothing should be visible as
none of the functions are implemented or otherwise crash on a nullptr.
This is expected as this is just a placeholder. The goal is to add shader compilation
+validation to this backend as one of the next steps so we can validate
changes to existing shaders on OpenGL, Metal and Vulkan at the same time.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D16338
