Fix building with `use_volk=yes` on MacOS

drivers/vulkan/SCsub

@@ -16,14 +16,14 @@ if env["use_volk"]:
 if env["platform"] == "android":
     env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_ANDROID_KHR"])
 elif env["platform"] == "ios":
-    env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_IOS_MVK"])
+    env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_IOS_MVK", "VK_USE_PLATFORM_METAL_EXT"])
 elif env["platform"] == "linuxbsd":
     if env["x11"]:
         env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_XLIB_KHR"])
     if env["wayland"]:
         env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_WAYLAND_KHR"])
 elif env["platform"] == "macos":
-    env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_MACOS_MVK"])
+    env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_MACOS_MVK", "VK_USE_PLATFORM_METAL_EXT"])
 elif env["platform"] == "windows":
     env.AppendUnique(CPPDEFINES=["VK_USE_PLATFORM_WIN32_KHR"])
 

drivers/vulkan/rendering_context_driver_vulkan.cpp

@@ -102,6 +102,10 @@ Error RenderingContextDriverVulkan::_initialize_instance_extensions() {
 	// This extension allows us to use the properties2 features to query additional device capabilities.
 	_register_requested_instance_extension(VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_EXTENSION_NAME, false);
 
+#if defined(USE_VOLK) && (defined(MACOS_ENABLED) || defined(IOS_ENABLED))
+	_register_requested_instance_extension(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME, true);
+#endif
+
 	// Only enable debug utils in verbose mode or DEV_ENABLED.
 	// End users would get spammed with messages of varying verbosity due to the
 	// mess that thirdparty layers/extensions and drivers seem to leave in their
@@ -360,6 +364,11 @@ Error RenderingContextDriverVulkan::_initialize_instance() {
 
 	VkInstanceCreateInfo instance_info = {};
 	instance_info.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;
+
+#if defined(USE_VOLK) && (defined(MACOS_ENABLED) || defined(IOS_ENABLED))
+	instance_info.flags = VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
+#endif
+
 	instance_info.pApplicationInfo = &app_info;
 	instance_info.enabledExtensionCount = enabled_extension_names.size();
 	instance_info.ppEnabledExtensionNames = enabled_extension_names.ptr();