Merge pull request #65227 from BastiaanOlij/complete_render_target_api

Implementing override functionality for XR

11 files changed, 340 insertions, 108 deletions

diff --git a/modules/openxr/SCsub b/modules/openxr/SCsub
index d4469b110b..5ac167ad98 100644
--- a/modules/openxr/SCsub
+++ b/modules/openxr/SCsub
@@ -92,6 +92,7 @@ if env["vulkan"]:
     env_openxr.add_source_files(module_obj, "extensions/openxr_vulkan_extension.cpp")
 
 env_openxr.add_source_files(module_obj, "extensions/openxr_palm_pose_extension.cpp")
+env_openxr.add_source_files(module_obj, "extensions/openxr_composition_layer_depth_extension.cpp")
 env_openxr.add_source_files(module_obj, "extensions/openxr_htc_vive_tracker_extension.cpp")
 env_openxr.add_source_files(module_obj, "extensions/openxr_hand_tracking_extension.cpp")
 env_openxr.add_source_files(module_obj, "extensions/openxr_fb_passthrough_extension_wrapper.cpp")
diff --git a/modules/openxr/extensions/openxr_composition_layer_depth_extension.cpp b/modules/openxr/extensions/openxr_composition_layer_depth_extension.cpp
new file mode 100644
index 0000000000..0f6aaf8afb
--- /dev/null
+++ b/modules/openxr/extensions/openxr_composition_layer_depth_extension.cpp
@@ -0,0 +1,58 @@
+/*************************************************************************/
+/*  openxr_composition_layer_depth_extension.cpp                         */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* 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.                */
+/*************************************************************************/
+
+#include "openxr_composition_layer_depth_extension.h"
+
+OpenXRCompositionLayerDepthExtension *OpenXRCompositionLayerDepthExtension::singleton = nullptr;
+
+OpenXRCompositionLayerDepthExtension *OpenXRCompositionLayerDepthExtension::get_singleton() {
+	return singleton;
+}
+
+OpenXRCompositionLayerDepthExtension::OpenXRCompositionLayerDepthExtension(OpenXRAPI *p_openxr_api) :
+		OpenXRExtensionWrapper(p_openxr_api) {
+	singleton = this;
+
+	request_extensions[XR_KHR_COMPOSITION_LAYER_DEPTH_EXTENSION_NAME] = &available;
+}
+
+OpenXRCompositionLayerDepthExtension::~OpenXRCompositionLayerDepthExtension() {
+	singleton = nullptr;
+}
+
+bool OpenXRCompositionLayerDepthExtension::is_available() {
+	return available;
+}
+
+XrCompositionLayerBaseHeader *OpenXRCompositionLayerDepthExtension::get_composition_layer() {
+	// Seems this is all done in our base layer... Just in case this changes...
+
+	return nullptr;
+}
diff --git a/modules/openxr/extensions/openxr_composition_layer_depth_extension.h b/modules/openxr/extensions/openxr_composition_layer_depth_extension.h
new file mode 100644
index 0000000000..9533783d83
--- /dev/null
+++ b/modules/openxr/extensions/openxr_composition_layer_depth_extension.h
@@ -0,0 +1,53 @@
+/*************************************************************************/
+/*  openxr_composition_layer_depth_extension.h                           */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* 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_COMPOSITION_LAYER_DEPTH_EXTENSION_H
+#define OPENXR_COMPOSITION_LAYER_DEPTH_EXTENSION_H
+
+#include "openxr_composition_layer_provider.h"
+#include "openxr_extension_wrapper.h"
+
+class OpenXRCompositionLayerDepthExtension : public OpenXRExtensionWrapper, public OpenXRCompositionLayerProvider {
+public:
+	static OpenXRCompositionLayerDepthExtension *get_singleton();
+
+	OpenXRCompositionLayerDepthExtension(OpenXRAPI *p_openxr_api);
+	virtual ~OpenXRCompositionLayerDepthExtension() override;
+
+	bool is_available();
+	virtual XrCompositionLayerBaseHeader *get_composition_layer() override;
+
+private:
+	static OpenXRCompositionLayerDepthExtension *singleton;
+
+	bool available = false;
+};
+
+#endif // OPENXR_COMPOSITION_LAYER_DEPTH_EXTENSION_H
diff --git a/modules/openxr/extensions/openxr_composition_layer_provider.h b/modules/openxr/extensions/openxr_composition_layer_provider.h
index ba51389f7d..a4c4cbe0c6 100644
--- a/modules/openxr/extensions/openxr_composition_layer_provider.h
+++ b/modules/openxr/extensions/openxr_composition_layer_provider.h
@@ -31,6 +31,7 @@
 #ifndef OPENXR_COMPOSITION_LAYER_PROVIDER_H
 #define OPENXR_COMPOSITION_LAYER_PROVIDER_H
 
+#include "openxr_extension_wrapper.h"
 #include <openxr/openxr.h>
 
 // Interface for OpenXR extensions that provide a composition layer.
diff --git a/modules/openxr/extensions/openxr_extension_wrapper.h b/modules/openxr/extensions/openxr_extension_wrapper.h
index 623c264e6e..c417c90d11 100644
--- a/modules/openxr/extensions/openxr_extension_wrapper.h
+++ b/modules/openxr/extensions/openxr_extension_wrapper.h
@@ -100,11 +100,12 @@ public:
 class OpenXRGraphicsExtensionWrapper : public OpenXRExtensionWrapper {
 public:
 	virtual void get_usable_swapchain_formats(Vector<int64_t> &p_usable_swap_chains) = 0;
+	virtual void get_usable_depth_formats(Vector<int64_t> &p_usable_swap_chains) = 0;
 	virtual String get_swapchain_format_name(int64_t p_swapchain_format) const = 0;
 	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) = 0;
 	virtual void cleanup_swapchain_graphics_data(void **p_swapchain_graphics_data) = 0;
 	virtual bool create_projection_fov(const XrFovf p_fov, double p_z_near, double p_z_far, Projection &r_camera_matrix) = 0;
-	virtual bool copy_render_target_to_image(RID p_from_render_target, void *p_swapchain_graphics_data, int p_image_index) = 0;
+	virtual RID get_texture(void *p_swapchain_graphics_data, int p_image_index) = 0;
 
 	OpenXRGraphicsExtensionWrapper(OpenXRAPI *p_openxr_api) :
 			OpenXRExtensionWrapper(p_openxr_api){};
diff --git a/modules/openxr/extensions/openxr_vulkan_extension.cpp b/modules/openxr/extensions/openxr_vulkan_extension.cpp
index f9e771c934..cc171cc42a 100644
--- a/modules/openxr/extensions/openxr_vulkan_extension.cpp
+++ b/modules/openxr/extensions/openxr_vulkan_extension.cpp
@@ -228,6 +228,12 @@ void OpenXRVulkanExtension::get_usable_swapchain_formats(Vector<int64_t> &p_usab
 	p_usable_swap_chains.push_back(VK_FORMAT_B8G8R8A8_UINT);
 }
 
+void OpenXRVulkanExtension::get_usable_depth_formats(Vector<int64_t> &p_usable_swap_chains) {
+	p_usable_swap_chains.push_back(VK_FORMAT_R32_SFLOAT);
+	p_usable_swap_chains.push_back(VK_FORMAT_D24_UNORM_S8_UINT);
+	p_usable_swap_chains.push_back(VK_FORMAT_D32_SFLOAT_S8_UINT);
+}
+
 bool OpenXRVulkanExtension::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) {
 	XrSwapchainImageVulkanKHR *images = nullptr;
 
@@ -271,7 +277,7 @@ bool OpenXRVulkanExtension::get_swapchain_image_data(XrSwapchain p_swapchain, in
 
 	RenderingDevice::DataFormat format = RenderingDevice::DATA_FORMAT_R8G8B8A8_SRGB;
 	RenderingDevice::TextureSamples samples = RenderingDevice::TEXTURE_SAMPLES_1;
-	uint64_t usage_flags = RenderingDevice::TEXTURE_USAGE_SAMPLING_BIT | RenderingDevice::TEXTURE_USAGE_COLOR_ATTACHMENT_BIT;
+	uint64_t usage_flags = RenderingDevice::TEXTURE_USAGE_SAMPLING_BIT;
 
 	switch (p_swapchain_format) {
 		case VK_FORMAT_R8G8B8A8_SRGB:
@@ -283,16 +289,32 @@ bool OpenXRVulkanExtension::get_swapchain_image_data(XrSwapchain p_swapchain, in
 			// will thus do an sRGB -> Linear conversion as expected.
 			// format = RenderingDevice::DATA_FORMAT_R8G8B8A8_SRGB;
 			format = RenderingDevice::DATA_FORMAT_R8G8B8A8_UNORM;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_COLOR_ATTACHMENT_BIT;
 			break;
 		case VK_FORMAT_B8G8R8A8_SRGB:
 			// format = RenderingDevice::DATA_FORMAT_B8G8R8A8_SRGB;
 			format = RenderingDevice::DATA_FORMAT_B8G8R8A8_UNORM;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_COLOR_ATTACHMENT_BIT;
 			break;
 		case VK_FORMAT_R8G8B8A8_UINT:
 			format = RenderingDevice::DATA_FORMAT_R8G8B8A8_UINT;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_COLOR_ATTACHMENT_BIT;
 			break;
 		case VK_FORMAT_B8G8R8A8_UINT:
 			format = RenderingDevice::DATA_FORMAT_B8G8R8A8_UINT;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_COLOR_ATTACHMENT_BIT;
+			break;
+		case VK_FORMAT_R32_SFLOAT:
+			format = RenderingDevice::DATA_FORMAT_R32_SFLOAT;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT;
+			break;
+		case VK_FORMAT_D24_UNORM_S8_UINT:
+			format = RenderingDevice::DATA_FORMAT_D24_UNORM_S8_UINT;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT;
+			break;
+		case VK_FORMAT_D32_SFLOAT_S8_UINT:
+			format = RenderingDevice::DATA_FORMAT_D32_SFLOAT_S8_UINT;
+			usage_flags |= RenderingDevice::TEXTURE_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT;
 			break;
 		default:
 			// continue with our default value
@@ -328,8 +350,7 @@ bool OpenXRVulkanExtension::get_swapchain_image_data(XrSwapchain p_swapchain, in
 			break;
 	}
 
-	Vector<RID> image_rids;
-	Vector<RID> framebuffers;
+	Vector<RID> texture_rids;
 
 	// create Godot texture objects for each entry in our swapchain
 	for (uint64_t i = 0; i < swapchain_length; i++) {
@@ -344,19 +365,10 @@ bool OpenXRVulkanExtension::get_swapchain_image_data(XrSwapchain p_swapchain, in
 				1,
 				p_array_size);
 
-		image_rids.push_back(image_rid);
-
-		{
-			Vector<RID> fb;
-			fb.push_back(image_rid);
-
-			RID fb_rid = rendering_device->framebuffer_create(fb, RenderingDevice::INVALID_ID, p_array_size);
-			framebuffers.push_back(fb_rid);
-		}
+		texture_rids.push_back(image_rid);
 	}
 
-	data->image_rids = image_rids;
-	data->framebuffers = framebuffers;
+	data->texture_rids = texture_rids;
 
 	memfree(images);
 
@@ -377,26 +389,12 @@ bool OpenXRVulkanExtension::create_projection_fov(const XrFovf p_fov, double p_z
 	return true;
 }
 
-bool OpenXRVulkanExtension::copy_render_target_to_image(RID p_from_render_target, void *p_swapchain_graphics_data, int p_image_index) {
+RID OpenXRVulkanExtension::get_texture(void *p_swapchain_graphics_data, int p_image_index) {
 	SwapchainGraphicsData *data = (SwapchainGraphicsData *)p_swapchain_graphics_data;
-	ERR_FAIL_NULL_V(data, false);
-	ERR_FAIL_COND_V(p_from_render_target.is_null(), false);
+	ERR_FAIL_NULL_V(data, RID());
 
-	RID source_image = RendererRD::TextureStorage::get_singleton()->render_target_get_rd_texture(p_from_render_target);
-	ERR_FAIL_COND_V(source_image.is_null(), false);
-
-	RID depth_image; // TODO implement
-
-	ERR_FAIL_INDEX_V(p_image_index, data->framebuffers.size(), false);
-	RID fb = data->framebuffers[p_image_index];
-	ERR_FAIL_COND_V(fb.is_null(), false);
-
-	// Our vulkan extension can only be used in conjunction with our vulkan renderer.
-	RendererRD::CopyEffects *copy_effects = RendererRD::CopyEffects::get_singleton();
-	ERR_FAIL_NULL_V(copy_effects, false);
-	copy_effects->copy_to_fb_rect(source_image, fb, Rect2i(), false, false, false, false, depth_image, data->is_multiview);
-
-	return true;
+	ERR_FAIL_INDEX_V(p_image_index, data->texture_rids.size(), RID());
+	return data->texture_rids[p_image_index];
 }
 
 void OpenXRVulkanExtension::cleanup_swapchain_graphics_data(void **p_swapchain_graphics_data) {
@@ -411,17 +409,11 @@ void OpenXRVulkanExtension::cleanup_swapchain_graphics_data(void **p_swapchain_g
 	RenderingDevice *rendering_device = rendering_server->get_rendering_device();
 	ERR_FAIL_NULL(rendering_device);
 
-	for (int i = 0; i < data->image_rids.size(); i++) {
-		// This should clean up our RIDs and associated texture objects but shouldn't destroy the images, they are owned by our XrSwapchain
-		rendering_device->free(data->image_rids[i]);
-	}
-	data->image_rids.clear();
-
-	for (int i = 0; i < data->framebuffers.size(); i++) {
+	for (int i = 0; i < data->texture_rids.size(); i++) {
 		// This should clean up our RIDs and associated texture objects but shouldn't destroy the images, they are owned by our XrSwapchain
-		rendering_device->free(data->framebuffers[i]);
+		rendering_device->free(data->texture_rids[i]);
 	}
-	data->framebuffers.clear();
+	data->texture_rids.clear();
 
 	memdelete(data);
 	*p_swapchain_graphics_data = nullptr;
diff --git a/modules/openxr/extensions/openxr_vulkan_extension.h b/modules/openxr/extensions/openxr_vulkan_extension.h
index d6e9917900..71abe3b166 100644
--- a/modules/openxr/extensions/openxr_vulkan_extension.h
+++ b/modules/openxr/extensions/openxr_vulkan_extension.h
@@ -69,11 +69,12 @@ public:
 	virtual bool create_vulkan_device(const VkDeviceCreateInfo *p_device_create_info, VkDevice *r_device) 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 bool copy_render_target_to_image(RID p_from_render_target, void *p_swapchain_graphics_data, int p_image_index) override;
+	virtual RID get_texture(void *p_swapchain_graphics_data, int p_image_index) override;
 
 private:
 	static OpenXRVulkanExtension *singleton;
@@ -81,8 +82,7 @@ private:
 
 	struct SwapchainGraphicsData {
 		bool is_multiview;
-		Vector<RID> image_rids;
-		Vector<RID> framebuffers;
+		Vector<RID> texture_rids;
 	};
 
 	bool check_graphics_api_support(XrVersion p_desired_version);
diff --git a/modules/openxr/openxr_api.cpp b/modules/openxr/openxr_api.cpp
index 16879ac4e5..8a69072793 100644
--- a/modules/openxr/openxr_api.cpp
+++ b/modules/openxr/openxr_api.cpp
@@ -49,6 +49,7 @@
 #include "extensions/openxr_vulkan_extension.h"
 #endif
 
+#include "extensions/openxr_composition_layer_depth_extension.h"
 #include "extensions/openxr_fb_passthrough_extension_wrapper.h"
 #include "extensions/openxr_hand_tracking_extension.h"
 #include "extensions/openxr_htc_vive_tracker_extension.h"
@@ -663,7 +664,7 @@ bool OpenXRAPI::is_swapchain_format_supported(int64_t p_swapchain_format) {
 	return false;
 }
 
-bool OpenXRAPI::create_main_swapchain() {
+bool OpenXRAPI::create_swapchains() {
 	ERR_FAIL_NULL_V(graphics_extension, false);
 	ERR_FAIL_COND_V(session == XR_NULL_HANDLE, false);
 
@@ -681,34 +682,36 @@ bool OpenXRAPI::create_main_swapchain() {
 		already rendering the next frame.
 
 		Finally an area we need to expand upon is that Foveated rendering is only enabled for the swap chain we create,
-		as we render 3D content into internal buffers that are copied into the swapchain, we don't get any of the performance gains
-		until such time as we implement VRS.
+		as we render 3D content into internal buffers that are copied into the swapchain, we do now have (basic) VRS support
 	*/
 
-	// Build a vector with swapchain formats we want to use, from best fit to worst
-	Vector<int64_t> usable_swapchain_formats;
-	int64_t swapchain_format_to_use = 0;
+	Size2 recommended_size = get_recommended_target_size();
 
-	graphics_extension->get_usable_swapchain_formats(usable_swapchain_formats);
+	// We start with our color swapchain...
+	{
+		// Build a vector with swapchain formats we want to use, from best fit to worst
+		Vector<int64_t> usable_swapchain_formats;
+		int64_t swapchain_format_to_use = 0;
 
-	// now find out which one is supported
-	for (int i = 0; i < usable_swapchain_formats.size() && swapchain_format_to_use == 0; i++) {
-		if (is_swapchain_format_supported(usable_swapchain_formats[i])) {
-			swapchain_format_to_use = usable_swapchain_formats[i];
-		}
-	}
+		graphics_extension->get_usable_swapchain_formats(usable_swapchain_formats);
 
-	if (swapchain_format_to_use == 0) {
-		swapchain_format_to_use = usable_swapchain_formats[0]; // just use the first one and hope for the best...
-		print_line("Couldn't find usable swap chain format, using", get_swapchain_format_name(swapchain_format_to_use), "instead.");
-	} else {
-		print_line("Using swap chain format:", get_swapchain_format_name(swapchain_format_to_use));
-	}
+		// now find out which one is supported
+		for (int i = 0; i < usable_swapchain_formats.size() && swapchain_format_to_use == 0; i++) {
+			if (is_swapchain_format_supported(usable_swapchain_formats[i])) {
+				swapchain_format_to_use = usable_swapchain_formats[i];
+			}
+		}
 
-	Size2 recommended_size = get_recommended_target_size();
+		if (swapchain_format_to_use == 0) {
+			swapchain_format_to_use = usable_swapchain_formats[0]; // just use the first one and hope for the best...
+			print_line("Couldn't find usable color swap chain format, using", get_swapchain_format_name(swapchain_format_to_use), "instead.");
+		} else {
+			print_line("Using color swap chain format:", get_swapchain_format_name(swapchain_format_to_use));
+		}
 
-	if (!create_swapchain(swapchain_format_to_use, recommended_size.width, recommended_size.height, view_configuration_views[0].recommendedSwapchainSampleCount, view_count, swapchain, &swapchain_graphics_data)) {
-		return false;
+		if (!create_swapchain(XR_SWAPCHAIN_USAGE_SAMPLED_BIT | XR_SWAPCHAIN_USAGE_COLOR_ATTACHMENT_BIT, swapchain_format_to_use, recommended_size.width, recommended_size.height, view_configuration_views[0].recommendedSwapchainSampleCount, view_count, swapchains[OPENXR_SWAPCHAIN_COLOR].swapchain, &swapchains[OPENXR_SWAPCHAIN_COLOR].swapchain_graphics_data)) {
+			return false;
+		}
 	}
 
 	views = (XrView *)memalloc(sizeof(XrView) * view_count);
@@ -717,18 +720,73 @@ bool OpenXRAPI::create_main_swapchain() {
 	projection_views = (XrCompositionLayerProjectionView *)memalloc(sizeof(XrCompositionLayerProjectionView) * view_count);
 	ERR_FAIL_NULL_V_MSG(projection_views, false, "OpenXR Couldn't allocate memory for projection views");
 
+	// We create our depth swapchain if:
+	// - we support our depth layer extension
+	// - we have our spacewarp extension (not yet implemented)
+	if (OpenXRCompositionLayerDepthExtension::get_singleton()->is_available()) {
+		// Build a vector with swapchain formats we want to use, from best fit to worst
+		Vector<int64_t> usable_swapchain_formats;
+		int64_t swapchain_format_to_use = 0;
+
+		graphics_extension->get_usable_depth_formats(usable_swapchain_formats);
+
+		// now find out which one is supported
+		for (int i = 0; i < usable_swapchain_formats.size() && swapchain_format_to_use == 0; i++) {
+			if (is_swapchain_format_supported(usable_swapchain_formats[i])) {
+				swapchain_format_to_use = usable_swapchain_formats[i];
+			}
+		}
+
+		if (swapchain_format_to_use == 0) {
+			swapchain_format_to_use = usable_swapchain_formats[0]; // just use the first one and hope for the best...
+			print_line("Couldn't find usable depth swap chain format, using", get_swapchain_format_name(swapchain_format_to_use), "instead.");
+		} else {
+			print_line("Using depth swap chain format:", get_swapchain_format_name(swapchain_format_to_use));
+		}
+
+		if (!create_swapchain(XR_SWAPCHAIN_USAGE_SAMPLED_BIT | XR_SWAPCHAIN_USAGE_DEPTH_STENCIL_ATTACHMENT_BIT, swapchain_format_to_use, recommended_size.width, recommended_size.height, view_configuration_views[0].recommendedSwapchainSampleCount, view_count, swapchains[OPENXR_SWAPCHAIN_DEPTH].swapchain, &swapchains[OPENXR_SWAPCHAIN_DEPTH].swapchain_graphics_data)) {
+			return false;
+		}
+
+		depth_views = (XrCompositionLayerDepthInfoKHR *)memalloc(sizeof(XrCompositionLayerDepthInfoKHR) * view_count);
+		ERR_FAIL_NULL_V_MSG(depth_views, false, "OpenXR Couldn't allocate memory for depth views");
+	}
+
+	// We create our velocity swapchain if:
+	// - we have our spacewarp extension (not yet implemented)
+	{
+		// TBD
+	}
+
 	for (uint32_t i = 0; i < view_count; i++) {
 		views[i].type = XR_TYPE_VIEW;
 		views[i].next = nullptr;
 
 		projection_views[i].type = XR_TYPE_COMPOSITION_LAYER_PROJECTION_VIEW;
 		projection_views[i].next = nullptr;
-		projection_views[i].subImage.swapchain = swapchain;
+		projection_views[i].subImage.swapchain = swapchains[OPENXR_SWAPCHAIN_COLOR].swapchain;
 		projection_views[i].subImage.imageArrayIndex = i;
 		projection_views[i].subImage.imageRect.offset.x = 0;
 		projection_views[i].subImage.imageRect.offset.y = 0;
 		projection_views[i].subImage.imageRect.extent.width = recommended_size.width;
 		projection_views[i].subImage.imageRect.extent.height = recommended_size.height;
+
+		if (OpenXRCompositionLayerDepthExtension::get_singleton()->is_available() && depth_views) {
+			projection_views[i].next = &depth_views[i];
+
+			depth_views[i].type = XR_TYPE_COMPOSITION_LAYER_DEPTH_INFO_KHR;
+			depth_views[i].next = nullptr;
+			depth_views[i].subImage.swapchain = swapchains[OPENXR_SWAPCHAIN_DEPTH].swapchain;
+			depth_views[i].subImage.imageArrayIndex = 0;
+			depth_views[i].subImage.imageRect.offset.x = 0;
+			depth_views[i].subImage.imageRect.offset.y = 0;
+			depth_views[i].subImage.imageRect.extent.width = recommended_size.width;
+			depth_views[i].subImage.imageRect.extent.height = recommended_size.height;
+			depth_views[i].minDepth = 0.0;
+			depth_views[i].maxDepth = 1.0;
+			depth_views[i].nearZ = 0.01; // Near and far Z will be set to the correct values in fill_projection_matrix
+			depth_views[i].farZ = 100.0;
+		}
 	};
 
 	return true;
@@ -740,7 +798,7 @@ void OpenXRAPI::destroy_session() {
 	}
 
 	if (graphics_extension) {
-		graphics_extension->cleanup_swapchain_graphics_data(&swapchain_graphics_data);
+		graphics_extension->cleanup_swapchain_graphics_data(&swapchains[OPENXR_SWAPCHAIN_COLOR].swapchain_graphics_data);
 	}
 
 	if (views != nullptr) {
@@ -753,9 +811,16 @@ void OpenXRAPI::destroy_session() {
 		projection_views = nullptr;
 	}
 
-	if (swapchain != XR_NULL_HANDLE) {
-		xrDestroySwapchain(swapchain);
-		swapchain = XR_NULL_HANDLE;
+	if (depth_views != nullptr) {
+		memfree(depth_views);
+		depth_views = nullptr;
+	}
+
+	for (int i = 0; i < OPENXR_SWAPCHAIN_MAX; i++) {
+		if (swapchains[i].swapchain != XR_NULL_HANDLE) {
+			xrDestroySwapchain(swapchains[i].swapchain);
+			swapchains[i].swapchain = XR_NULL_HANDLE;
+		}
 	}
 
 	if (supported_swapchain_formats != nullptr) {
@@ -789,7 +854,7 @@ void OpenXRAPI::destroy_session() {
 	}
 }
 
-bool OpenXRAPI::create_swapchain(int64_t p_swapchain_format, uint32_t p_width, uint32_t p_height, uint32_t p_sample_count, uint32_t p_array_size, XrSwapchain &r_swapchain, void **r_swapchain_graphics_data) {
+bool OpenXRAPI::create_swapchain(XrSwapchainUsageFlags p_usage_flags, int64_t p_swapchain_format, uint32_t p_width, uint32_t p_height, uint32_t p_sample_count, uint32_t p_array_size, XrSwapchain &r_swapchain, void **r_swapchain_graphics_data) {
 	ERR_FAIL_COND_V(session == XR_NULL_HANDLE, false);
 	ERR_FAIL_NULL_V(graphics_extension, false);
 
@@ -807,7 +872,7 @@ bool OpenXRAPI::create_swapchain(int64_t p_swapchain_format, uint32_t p_width, u
 		XR_TYPE_SWAPCHAIN_CREATE_INFO, // type
 		next_pointer, // next
 		0, // createFlags
-		XR_SWAPCHAIN_USAGE_SAMPLED_BIT | XR_SWAPCHAIN_USAGE_COLOR_ATTACHMENT_BIT, // usageFlags
+		p_usage_flags, // usageFlags
 		p_swapchain_format, // format
 		p_sample_count, // sampleCount
 		p_width, // width
@@ -871,7 +936,7 @@ bool OpenXRAPI::on_state_ready() {
 	// That will be very very ugly
 	// The other possibility is to create a separate OpenXRViewport type specifically for this goal as part of our OpenXR module
 
-	if (!create_main_swapchain()) {
+	if (!create_swapchains()) {
 		return false;
 	}
 
@@ -1304,6 +1369,15 @@ bool OpenXRAPI::get_view_projection(uint32_t p_view, double p_z_near, double p_z
 		return false;
 	}
 
+	// if we're using depth views, make sure we update our near and far there...
+	if (depth_views != nullptr) {
+		for (uint32_t i = 0; i < view_count; i++) {
+			depth_views[i].nearZ = p_z_near;
+			depth_views[i].farZ = p_z_far;
+		}
+	}
+
+	// now update our projection
 	return graphics_extension->create_projection_fov(views[p_view].fov, p_z_near, p_z_far, p_camera_matrix);
 }
 
@@ -1442,15 +1516,15 @@ bool OpenXRAPI::process() {
 	return true;
 }
 
-bool OpenXRAPI::acquire_image(XrSwapchain p_swapchain, uint32_t &r_image_index) {
-	ERR_FAIL_COND_V(image_acquired, true); // this was not released when it should be, error out and re-use...
+bool OpenXRAPI::acquire_image(OpenXRSwapChainInfo &p_swapchain) {
+	ERR_FAIL_COND_V(p_swapchain.image_acquired, true); // this was not released when it should be, error out and re-use...
 
 	XrResult result;
 	XrSwapchainImageAcquireInfo swapchain_image_acquire_info = {
 		XR_TYPE_SWAPCHAIN_IMAGE_ACQUIRE_INFO, // type
 		nullptr // next
 	};
-	result = xrAcquireSwapchainImage(p_swapchain, &swapchain_image_acquire_info, &r_image_index);
+	result = xrAcquireSwapchainImage(p_swapchain.swapchain, &swapchain_image_acquire_info, &p_swapchain.image_index);
 	if (XR_FAILED(result)) {
 		print_line("OpenXR: failed to acquire swapchain image [", get_error_string(result), "]");
 		return false;
@@ -1462,7 +1536,7 @@ bool OpenXRAPI::acquire_image(XrSwapchain p_swapchain, uint32_t &r_image_index)
 		17000000 // timeout in nanoseconds
 	};
 
-	result = xrWaitSwapchainImage(p_swapchain, &swapchain_image_wait_info);
+	result = xrWaitSwapchainImage(p_swapchain.swapchain, &swapchain_image_wait_info);
 	if (XR_FAILED(result)) {
 		print_line("OpenXR: failed to wait for swapchain image [", get_error_string(result), "]");
 		return false;
@@ -1471,12 +1545,12 @@ bool OpenXRAPI::acquire_image(XrSwapchain p_swapchain, uint32_t &r_image_index)
 	return true;
 }
 
-bool OpenXRAPI::release_image(XrSwapchain p_swapchain) {
+bool OpenXRAPI::release_image(OpenXRSwapChainInfo &p_swapchain) {
 	XrSwapchainImageReleaseInfo swapchain_image_release_info = {
 		XR_TYPE_SWAPCHAIN_IMAGE_RELEASE_INFO, // type
 		nullptr // next
 	};
-	XrResult result = xrReleaseSwapchainImage(swapchain, &swapchain_image_release_info);
+	XrResult result = xrReleaseSwapchainImage(p_swapchain.swapchain, &swapchain_image_release_info);
 	if (XR_FAILED(result)) {
 		print_line("OpenXR: failed to release swapchain image! [", get_error_string(result), "]");
 		return false;
@@ -1590,28 +1664,41 @@ bool OpenXRAPI::pre_draw_viewport(RID p_render_target) {
 
 	// TODO: at some point in time we may support multiple viewports in which case we need to handle that...
 
+	// Acquire our images
+	for (int i = 0; i < OPENXR_SWAPCHAIN_MAX; i++) {
+		if (!swapchains[i].image_acquired && swapchains[i].swapchain != XR_NULL_HANDLE) {
+			if (!acquire_image(swapchains[i])) {
+				return false;
+			}
+			swapchains[i].image_acquired = true;
+		}
+	}
+
 	return true;
 }
 
+RID OpenXRAPI::get_color_texture() {
+	if (swapchains[OPENXR_SWAPCHAIN_COLOR].image_acquired) {
+		return graphics_extension->get_texture(swapchains[OPENXR_SWAPCHAIN_COLOR].swapchain_graphics_data, swapchains[OPENXR_SWAPCHAIN_COLOR].image_index);
+	} else {
+		return RID();
+	}
+}
+
+RID OpenXRAPI::get_depth_texture() {
+	if (swapchains[OPENXR_SWAPCHAIN_DEPTH].image_acquired) {
+		return graphics_extension->get_texture(swapchains[OPENXR_SWAPCHAIN_DEPTH].swapchain_graphics_data, swapchains[OPENXR_SWAPCHAIN_DEPTH].image_index);
+	} else {
+		return RID();
+	}
+}
+
 void OpenXRAPI::post_draw_viewport(RID p_render_target) {
 	if (!can_render()) {
 		return;
 	}
 
-	// TODO: at some point in time we may support multiple viewports in which case we need to handle that...
-
-	// TODO: if we can get PR 51179 to work properly we can change away from this approach and move this into get_external_texture or something
-	if (!image_acquired) {
-		if (!acquire_image(swapchain, image_index)) {
-			return;
-		}
-		image_acquired = true;
-
-		// print_line("OpenXR: acquired image " + itos(image_index) + ", copying...");
-
-		// Copy our buffer into our swap chain (remove once PR 51179 is done)
-		graphics_extension->copy_render_target_to_image(p_render_target, swapchain_graphics_data, image_index);
-	}
+	// Nothing to do here at this point in time...
 };
 
 void OpenXRAPI::end_frame() {
@@ -1623,7 +1710,7 @@ void OpenXRAPI::end_frame() {
 		return;
 	}
 
-	if (frame_state.shouldRender && view_pose_valid && !image_acquired) {
+	if (frame_state.shouldRender && view_pose_valid && !swapchains[OPENXR_SWAPCHAIN_COLOR].image_acquired) {
 		print_line("OpenXR: No viewport was marked with use_xr, there is no rendered output!");
 	}
 
@@ -1631,7 +1718,7 @@ void OpenXRAPI::end_frame() {
 	// - shouldRender set to true
 	// - a valid view pose for projection_views[eye].pose to submit layer
 	// - an image to render
-	if (!frame_state.shouldRender || !view_pose_valid || !image_acquired) {
+	if (!frame_state.shouldRender || !view_pose_valid || !swapchains[OPENXR_SWAPCHAIN_COLOR].image_acquired) {
 		// submit 0 layers when we shouldn't render
 		XrFrameEndInfo frame_end_info = {
 			XR_TYPE_FRAME_END_INFO, // type
@@ -1652,10 +1739,12 @@ void OpenXRAPI::end_frame() {
 	}
 
 	// release our swapchain image if we acquired it
-	if (image_acquired) {
-		image_acquired = false; // whether we succeed or not, consider this released.
+	for (int i = 0; i < OPENXR_SWAPCHAIN_MAX; i++) {
+		if (swapchains[i].image_acquired) {
+			swapchains[i].image_acquired = false; // whether we succeed or not, consider this released.
 
-		release_image(swapchain);
+			release_image(swapchains[i]);
+		}
 	}
 
 	for (uint32_t eye = 0; eye < view_count; eye++) {
@@ -1763,6 +1852,7 @@ OpenXRAPI::OpenXRAPI() {
 
 	// register our other extensions
 	register_extension_wrapper(memnew(OpenXRPalmPoseExtension(this)));
+	register_extension_wrapper(memnew(OpenXRCompositionLayerDepthExtension(this)));
 	register_extension_wrapper(memnew(OpenXRHTCViveTrackerExtension(this)));
 	register_extension_wrapper(memnew(OpenXRHandTrackingExtension(this)));
 	register_extension_wrapper(memnew(OpenXRFbPassthroughExtensionWrapper(this)));
diff --git a/modules/openxr/openxr_api.h b/modules/openxr/openxr_api.h
index 316886239e..bd69432dcb 100644
--- a/modules/openxr/openxr_api.h
+++ b/modules/openxr/openxr_api.h
@@ -120,15 +120,28 @@ private:
 
 	OpenXRGraphicsExtensionWrapper *graphics_extension = nullptr;
 	XrSystemGraphicsProperties graphics_properties;
-	void *swapchain_graphics_data = nullptr;
-	uint32_t image_index = 0;
-	bool image_acquired = false;
 
 	uint32_t view_count = 0;
 	XrViewConfigurationView *view_configuration_views = nullptr;
 	XrView *views = nullptr;
 	XrCompositionLayerProjectionView *projection_views = nullptr;
-	XrSwapchain swapchain = XR_NULL_HANDLE;
+	XrCompositionLayerDepthInfoKHR *depth_views = nullptr; // Only used by Composition Layer Depth Extension if available
+
+	enum OpenXRSwapChainTypes {
+		OPENXR_SWAPCHAIN_COLOR,
+		OPENXR_SWAPCHAIN_DEPTH,
+		// OPENXR_SWAPCHAIN_VELOCITY,
+		OPENXR_SWAPCHAIN_MAX
+	};
+
+	struct OpenXRSwapChainInfo {
+		XrSwapchain swapchain = XR_NULL_HANDLE;
+		void *swapchain_graphics_data = nullptr;
+		uint32_t image_index = 0;
+		bool image_acquired = false;
+	};
+
+	OpenXRSwapChainInfo swapchains[OPENXR_SWAPCHAIN_MAX];
 
 	XrSpace play_space = XR_NULL_HANDLE;
 	XrSpace view_space = XR_NULL_HANDLE;
@@ -212,13 +225,13 @@ private:
 	bool setup_spaces();
 	bool load_supported_swapchain_formats();
 	bool is_swapchain_format_supported(int64_t p_swapchain_format);
-	bool create_main_swapchain();
+	bool create_swapchains();
 	void destroy_session();
 
 	// swapchains
-	bool create_swapchain(int64_t p_swapchain_format, uint32_t p_width, uint32_t p_height, uint32_t p_sample_count, uint32_t p_array_size, XrSwapchain &r_swapchain, void **r_swapchain_graphics_data);
-	bool acquire_image(XrSwapchain p_swapchain, uint32_t &r_image_index);
-	bool release_image(XrSwapchain p_swapchain);
+	bool create_swapchain(XrSwapchainUsageFlags p_usage_flags, int64_t p_swapchain_format, uint32_t p_width, uint32_t p_height, uint32_t p_sample_count, uint32_t p_array_size, XrSwapchain &r_swapchain, void **r_swapchain_graphics_data);
+	bool acquire_image(OpenXRSwapChainInfo &p_swapchain);
+	bool release_image(OpenXRSwapChainInfo &p_swapchain);
 
 	// action map
 	struct Tracker { // Trackers represent tracked physical objects such as controllers, pucks, etc.
@@ -318,6 +331,8 @@ public:
 
 	void pre_render();
 	bool pre_draw_viewport(RID p_render_target);
+	RID get_color_texture();
+	RID get_depth_texture();
 	void post_draw_viewport(RID p_render_target);
 	void end_frame();
 
diff --git a/modules/openxr/openxr_interface.cpp b/modules/openxr/openxr_interface.cpp
index 01e148e00f..31dc2bbf43 100644
--- a/modules/openxr/openxr_interface.cpp
+++ b/modules/openxr/openxr_interface.cpp
@@ -648,6 +648,22 @@ Projection OpenXRInterface::get_projection_for_view(uint32_t p_view, double p_as
 	return cm;
 }
 
+RID OpenXRInterface::get_color_texture() {
+	if (openxr_api) {
+		return openxr_api->get_color_texture();
+	} else {
+		return RID();
+	}
+}
+
+RID OpenXRInterface::get_depth_texture() {
+	if (openxr_api) {
+		return openxr_api->get_depth_texture();
+	} else {
+		return RID();
+	}
+}
+
 void OpenXRInterface::process() {
 	if (openxr_api) {
 		// do our normal process
@@ -707,6 +723,7 @@ bool OpenXRInterface::pre_draw_viewport(RID p_render_target) {
 Vector<BlitToScreen> OpenXRInterface::post_draw_viewport(RID p_render_target, const Rect2 &p_screen_rect) {
 	Vector<BlitToScreen> blit_to_screen;
 
+#ifndef ANDROID_ENABLED
 	// If separate HMD we should output one eye to screen
 	if (p_screen_rect != Rect2()) {
 		BlitToScreen blit;
@@ -732,6 +749,7 @@ Vector<BlitToScreen> OpenXRInterface::post_draw_viewport(RID p_render_target, co
 		blit.dst_rect = dst_rect;
 		blit_to_screen.push_back(blit);
 	}
+#endif
 
 	if (openxr_api) {
 		openxr_api->post_draw_viewport(p_render_target);
diff --git a/modules/openxr/openxr_interface.h b/modules/openxr/openxr_interface.h
index 3765f18637..72935b039c 100644
--- a/modules/openxr/openxr_interface.h
+++ b/modules/openxr/openxr_interface.h
@@ -126,6 +126,9 @@ public:
 	virtual Transform3D get_transform_for_view(uint32_t p_view, const Transform3D &p_cam_transform) override;
 	virtual Projection get_projection_for_view(uint32_t p_view, double p_aspect, double p_z_near, double p_z_far) override;
 
+	virtual RID get_color_texture() override;
+	virtual RID get_depth_texture() override;
+
 	virtual void process() override;
 	virtual void pre_render() override;
 	bool pre_draw_viewport(RID p_render_target) override;