GPU: Add placeholder for Vulkan backend.

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

1 files changed, 3 insertions, 1 deletions

diff --git a/source/blender/python/gpu/gpu_py_platform.c b/source/blender/python/gpu/gpu_py_platform.c
index 51366d199b0..c6e964405fa 100644
--- a/source/blender/python/gpu/gpu_py_platform.c
+++ b/source/blender/python/gpu/gpu_py_platform.c
@@ -89,11 +89,13 @@ PyDoc_STRVAR(pygpu_platform_backend_type_get_doc,
              "\n"
              "   Get actuve GPU backend.\n"
              "\n"
-             "   :return: Backend type ('OPENGL', 'METAL', 'NONE', 'UNKNOWN').\n"
+             "   :return: Backend type ('OPENGL', 'VULKAN', 'METAL', 'NONE', 'UNKNOWN').\n"
              "   :rtype: str\n");
 static PyObject *pygpu_platform_backend_type_get(PyObject *UNUSED(self))
 {
   switch (GPU_backend_get_type()) {
+    case GPU_BACKEND_VULKAN:
+      return PyUnicode_FromString("VULKAN");
     case GPU_BACKEND_METAL:
       return PyUnicode_FromString("METAL");
     case GPU_BACKEND_NONE: