OpenXR: Add Metal support

modules/openxr/extensions/SCsub

@@ -13,6 +13,8 @@ if env["platform"] == "android":
     env_openxr.add_source_files(module_obj, "platform/openxr_android_extension.cpp")
 if env["vulkan"]:
     env_openxr.add_source_files(module_obj, "platform/openxr_vulkan_extension.cpp")
+if env["metal"]:
+    env_openxr.add_source_files(module_obj, "platform/openxr_metal_extension.mm")
 if env["opengl3"] and env["platform"] != "macos":
     env_openxr.add_source_files(module_obj, "platform/openxr_opengl_extension.cpp")
 

modules/openxr/extensions/platform/openxr_metal_extension.h

@@ -0,0 +1,73 @@
+/**************************************************************************/
+/*  openxr_metal_extension.h                                              */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#ifndef OPENXR_METAL_EXTENSION_H
+#define OPENXR_METAL_EXTENSION_H
+
+#include "../../openxr_api.h"
+#include "../../util.h"
+#include "../openxr_extension_wrapper.h"
+
+#include "core/templates/vector.h"
+
+// Always include this as late as possible.
+#include "../../openxr_platform_inc.h"
+
+class OpenXRMetalExtension : public OpenXRGraphicsExtensionWrapper {
+public:
+	virtual HashMap<String, bool *> get_requested_extensions() override;
+
+	virtual void on_instance_created(const XrInstance p_instance) override;
+	virtual void *set_session_create_and_get_next_pointer(void *p_next_pointer) override;
+
+	virtual void get_usable_swapchain_formats(Vector<int64_t> &p_usable_swap_chains) override;
+	virtual void get_usable_depth_formats(Vector<int64_t> &p_usable_swap_chains) override;
+	virtual String get_swapchain_format_name(int64_t p_swapchain_format) const override;
+	virtual bool get_swapchain_image_data(XrSwapchain p_swapchain, int64_t p_swapchain_format, uint32_t p_width, uint32_t p_height, uint32_t p_sample_count, uint32_t p_array_size, void **r_swapchain_graphics_data) override;
+	virtual void cleanup_swapchain_graphics_data(void **p_swapchain_graphics_data) override;
+	virtual bool create_projection_fov(const XrFovf p_fov, double p_z_near, double p_z_far, Projection &r_camera_matrix) override;
+	virtual RID get_texture(void *p_swapchain_graphics_data, int p_image_index) override;
+
+private:
+	static XrGraphicsBindingMetalKHR graphics_binding_metal;
+
+	struct SwapchainGraphicsData {
+		bool is_multiview;
+		Vector<RID> texture_rids;
+		Vector<RID> other_rids;
+	};
+
+	bool check_graphics_api_support();
+
+	EXT_PROTO_XRRESULT_FUNC3(xrGetMetalGraphicsRequirementsKHR, (XrInstance), p_instance, (XrSystemId), p_system_id, (XrGraphicsRequirementsMetalKHR *), p_graphics_requirements)
+	EXT_PROTO_XRRESULT_FUNC4(xrEnumerateSwapchainImages, (XrSwapchain), p_swapchain, (uint32_t), p_image_capacity_input, (uint32_t *), p_image_count_output, (XrSwapchainImageBaseHeader *), p_images)
+};
+
+#endif // OPENXR_METAL_EXTENSION_H