Metal: Initial Implementation of Metal Backend for GPU Module.

Adding WITH_METAL option to CMAKE to guard compilation for macOS only. Implemented stub METALBackend to mirror GPUBackend interface and added capabilities initialisation, along with API initialisation paths.

Global rendering coordination commands added to backend with GPU_render_begin and GPU_render_end() commands globally wrapping GPU work. This is required for Metal to ensure temporary resources are generated within an NSAutoReleasePool and freed accordingly.

Authored by Apple: Michael Parkin-White, Vil Harvey, Marco Giordano, Michael Jones, Morteza Mostajabodaveh, Jason Fielder

Ref T96261

Reviewed By: fclem

Maniphest Tasks: T96261

Differential Revision: https://developer.blender.org/D14293

1 files changed, 10 insertions, 1 deletions

diff --git a/source/blender/gpu/GPU_platform.h b/source/blender/gpu/GPU_platform.h
index d5a0fcfa921..bd20d0c7db1 100644
--- a/source/blender/gpu/GPU_platform.h
+++ b/source/blender/gpu/GPU_platform.h
@@ -12,6 +12,13 @@
 
 /* GPU platform support */
 
+typedef enum eGPUBackendType {
+  GPU_BACKEND_NONE = 0,
+  GPU_BACKEND_OPENGL = 1 << 0,
+  GPU_BACKEND_METAL = 1 << 1,
+  GPU_BACKEND_ANY = 0xFFFFFFFFu
+} eGPUBackendType;
+
 /* GPU Types */
 typedef enum eGPUDeviceType {
   GPU_DEVICE_NVIDIA = (1 << 0),
@@ -51,8 +58,10 @@ extern "C" {
 #endif
 
 /* GPU Types */
-
+/* TODO: Verify all use-cases of GPU_type_matches to determine which graphics API it should apply to, and replace
+ * with `GPU_type_matches_ex` where appropriate. */
 bool GPU_type_matches(eGPUDeviceType device, eGPUOSType os, eGPUDriverType driver);
+bool GPU_type_matches_ex(eGPUDeviceType device, eGPUOSType os, eGPUDriverType driver, eGPUBackendType backend);
 
 eGPUSupportLevel GPU_platform_support_level(void);
 const char *GPU_platform_vendor(void);