Add Passthrough extension wrapper

1 files changed, 254 insertions, 0 deletions

diff --git a/modules/openxr/extensions/openxr_fb_passthrough_extension_wrapper.h b/modules/openxr/extensions/openxr_fb_passthrough_extension_wrapper.h
new file mode 100644
index 0000000000..1959f3fdc4
--- /dev/null
+++ b/modules/openxr/extensions/openxr_fb_passthrough_extension_wrapper.h
@@ -0,0 +1,254 @@
+/*************************************************************************/
+/*  openxr_fb_passthrough_extension_wrapper.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_FB_PASSTHROUGH_EXTENSION_WRAPPER_H
+#define OPENXR_FB_PASSTHROUGH_EXTENSION_WRAPPER_H
+
+#include "../openxr_api.h"
+#include "../util.h"
+
+#include "openxr_composition_layer_provider.h"
+#include "openxr_extension_wrapper.h"
+
+#include <map>
+
+class Viewport;
+
+// Wrapper for the set of Facebook XR passthrough extensions.
+class OpenXRFbPassthroughExtensionWrapper : public OpenXRExtensionWrapper, public OpenXRCompositionLayerProvider {
+	friend class OpenXRAPI;
+
+public:
+	void on_instance_created(const XrInstance instance) override;
+
+	void on_session_created(const XrSession session) override;
+
+	void on_session_destroyed() override;
+
+	void on_instance_destroyed() override;
+
+	XrCompositionLayerBaseHeader *get_composition_layer() override;
+
+	bool is_passthrough_supported() {
+		return fb_passthrough_ext;
+	}
+
+	bool is_passthrough_enabled();
+
+	bool start_passthrough();
+
+	void stop_passthrough();
+
+	static OpenXRFbPassthroughExtensionWrapper *get_singleton();
+
+protected:
+	OpenXRFbPassthroughExtensionWrapper(OpenXRAPI *p_openxr_api);
+	~OpenXRFbPassthroughExtensionWrapper();
+
+private:
+	// Create a passthrough feature
+	EXT_PROTO_XRRESULT_FUNC3(xrCreatePassthroughFB,
+			(XrSession), session,
+			(const XrPassthroughCreateInfoFB *), create_info,
+			(XrPassthroughFB *), feature_out)
+
+	// Destroy a previously created passthrough feature
+	EXT_PROTO_XRRESULT_FUNC1(xrDestroyPassthroughFB, (XrPassthroughFB), feature)
+
+	//*** Passthrough feature state management functions *********
+	// Start the passthrough feature
+	EXT_PROTO_XRRESULT_FUNC1(xrPassthroughStartFB, (XrPassthroughFB), passthrough)
+	// Pause the passthrough feature
+	EXT_PROTO_XRRESULT_FUNC1(xrPassthroughPauseFB, (XrPassthroughFB), passthrough)
+
+	EXT_PROTO_XRRESULT_FUNC3(xrCreatePassthroughLayerFB, (XrSession), session,
+			(const XrPassthroughLayerCreateInfoFB *), config,
+			(XrPassthroughLayerFB *), layer_out)
+
+	EXT_PROTO_XRRESULT_FUNC1(xrDestroyPassthroughLayerFB, (XrPassthroughLayerFB), layer)
+
+	EXT_PROTO_XRRESULT_FUNC1(xrPassthroughLayerPauseFB, (XrPassthroughLayerFB), layer)
+	EXT_PROTO_XRRESULT_FUNC1(xrPassthroughLayerResumeFB, (XrPassthroughLayerFB), layer)
+
+	// Set the style of an existing passthrough layer. If the enabled feature set
+	// doesn’t change, this is a lightweight operation that can be called in every
+	// frame to animate the style. Changes that may incur a bigger cost:
+	// - Enabling/disabling the color mapping, or changing the type of mapping
+	//   (monochromatic to RGBA or back).
+	// - Changing `textureOpacityFactor` from 0 to non-zero or vice versa
+	// - Changing `edgeColor[3]` from 0 to non-zero or vice versa
+	// NOTE: For XR_FB_passthrough, all color values are treated as linear.
+	EXT_PROTO_XRRESULT_FUNC2(xrPassthroughLayerSetStyleFB,
+			(XrPassthroughLayerFB), layer,
+			(const XrPassthroughStyleFB *), style)
+
+	// Create a geometry instance to be used as a projection surface for passthrough.
+	// A geometry instance assigns a triangle mesh as part of the specified layer's
+	// projection surface.
+	// The operation is only valid if the passthrough layer's purpose has been set to
+	// `XR_PASSTHROUGH_LAYER_PURPOSE_PROJECTED_FB`. Otherwise, the call this function will
+	// result in an error. In the specified layer, Passthrough will be visible where the view
+	// is covered by the user-specified geometries.
+	//
+	// A triangle mesh object can be instantiated multiple times - in the same or different layers'
+	// projection surface. Each instantiation has its own transformation, which
+	// can be updated using `xrGeometryInstanceSetTransformFB`.
+	EXT_PROTO_XRRESULT_FUNC3(xrCreateGeometryInstanceFB,
+			(XrSession), session,
+			(const XrGeometryInstanceCreateInfoFB *), create_info,
+			(XrGeometryInstanceFB *), out_geometry_instance)
+
+	// Destroys a previously created geometry instance from passthrough rendering.
+	// This removes the geometry instance from passthrough rendering.
+	// The operation has no effect on other instances or the underlying mesh.
+	EXT_PROTO_XRRESULT_FUNC1(xrDestroyGeometryInstanceFB, (XrGeometryInstanceFB), instance)
+
+	// Update the transformation of a passthrough geometry instance.
+	EXT_PROTO_XRRESULT_FUNC2(xrGeometryInstanceSetTransformFB,
+			(XrGeometryInstanceFB), instance,
+			(const XrGeometryInstanceTransformFB *), transformation)
+
+	// Create a triangle mesh geometry object.
+	// Depending on the behavior flags, the mesh could be created immutable (data is assigned
+	// at creation and cannot be changed) or mutable (the mesh is created empty and can be updated
+	// by calling begin/end update functions).
+	EXT_PROTO_XRRESULT_FUNC3(xrCreateTriangleMeshFB,
+			(XrSession), session,
+			(const XrTriangleMeshCreateInfoFB *), create_info,
+			(XrTriangleMeshFB *), out_triangle_mesh)
+
+	// Destroy an `XrTriangleMeshFB` object along with its data. The mesh buffers must not be
+	// accessed anymore after their parent mesh object has been destroyed.
+	EXT_PROTO_XRRESULT_FUNC1(xrDestroyTriangleMeshFB, (XrTriangleMeshFB), mesh)
+
+	// Retrieve a pointer to the vertex buffer. The vertex buffer is structured as an array of 3 floats
+	// per vertex representing x, y, and z: `[x0, y0, z0, x1, y1, z1, ...]`. The size of the buffer is
+	// `maxVertexCount * 3` floats. The application must call `xrTriangleMeshBeginUpdateFB` or
+	// `xrTriangleMeshBeginVertexBufferUpdateFB` before making modifications to the vertex
+	// buffer. The buffer location is guaranteed to remain constant over the lifecycle of the mesh
+	// object.
+	EXT_PROTO_XRRESULT_FUNC2(xrTriangleMeshGetVertexBufferFB,
+			(XrTriangleMeshFB), mesh,
+			(XrVector3f **), out_vertex_buffer)
+
+	// Retrieve the index buffer that defines the topology of the triangle mesh. Each triplet of
+	// consecutive elements point to three vertices in the vertex buffer and thus form a triangle. The
+	// size of each element is `indexElementSize` bytes, and thus the size of the buffer is
+	// `maxTriangleCount * 3 * indexElementSize` bytes. The application must call
+	// `xrTriangleMeshBeginUpdateFB` before making modifications to the index buffer. The buffer
+	// location is guaranteed to remain constant over the lifecycle of the mesh object.
+	EXT_PROTO_XRRESULT_FUNC2(xrTriangleMeshGetIndexBufferFB,
+			(XrTriangleMeshFB), mesh,
+			(uint32_t **), out_index_buffer)
+
+	// Begin updating the mesh buffer data. The application must call this function before it makes any
+	// modifications to the buffers retrieved by `xrTriangleMeshGetVertexBufferFB` and
+	// `xrTriangleMeshGetIndexBufferFB`. If only the vertex buffer needs to be updated,
+	// `xrTriangleMeshBeginVertexBufferUpdateFB` can be used instead. To commit the
+	// modifications, the application must call `xrTriangleMeshEndUpdateFB`.
+	EXT_PROTO_XRRESULT_FUNC1(xrTriangleMeshBeginUpdateFB, (XrTriangleMeshFB), mesh)
+
+	// Signal the API that the application has finished updating the mesh buffers after a call to
+	// `xrTriangleMeshBeginUpdateFB`. `vertexCount` and `triangleCount` specify the actual
+	// number of primitives that make up the mesh after the update. They must be larger than zero but
+	// smaller or equal to the maximum counts defined at create time. Buffer data beyond these counts
+	// is ignored.
+	EXT_PROTO_XRRESULT_FUNC3(xrTriangleMeshEndUpdateFB,
+			(XrTriangleMeshFB), mesh,
+			(uint32_t), vertexCount,
+			(uint32_t), triangle_count)
+
+	// Update the vertex positions of a triangle mesh. Can only be called once the mesh topology has
+	// been set using `xrTriangleMeshBeginUpdateFB`/`xrTriangleMeshEndUpdateFB`. The
+	// vertex count is defined by the last invocation to `xrTriangleMeshEndUpdateFB`. Once the
+	// modification is done, `xrTriangleMeshEndVertexBufferUpdateFB` must be called.
+	EXT_PROTO_XRRESULT_FUNC2(xrTriangleMeshBeginVertexBufferUpdateFB,
+			(XrTriangleMeshFB), mesh,
+			(uint32_t *), out_vertex_count)
+
+	// Signal the API that the contents of the vertex buffer data has been updated
+	// after a call to `xrTriangleMeshBeginVertexBufferUpdateFB`.
+	EXT_PROTO_XRRESULT_FUNC1(xrTriangleMeshEndVertexBufferUpdateFB, (XrTriangleMeshFB), mesh)
+
+	bool initialize_fb_passthrough_extension(const XrInstance instance);
+
+	bool initialize_fb_triangle_mesh_extension(const XrInstance instance);
+
+	void cleanup();
+
+	// TODO: Temporary workaround (https://github.com/GodotVR/godot_openxr/issues/138)
+	//  Address a bug in the passthrough api where XR_ERROR_UNEXPECTED_STATE_PASSTHROUGH_FB is
+	//  returned even when the operation is valid on Meta Quest devices.
+	//  The issue should be addressed on that platform in OS release v37.
+	inline bool is_valid_passthrough_result(XrResult result, const char *format) {
+		return openxr_api->xr_result(result, format) || result == XR_ERROR_UNEXPECTED_STATE_PASSTHROUGH_FB;
+	}
+
+	Viewport *get_main_viewport();
+
+	bool is_composition_passthrough_layer_ready();
+
+	static OpenXRFbPassthroughExtensionWrapper *singleton;
+
+	bool fb_passthrough_ext = false; // required for any passthrough functionality
+	bool fb_triangle_mesh_ext = false; // only use for projected passthrough
+
+	XrPassthroughCreateInfoFB passthrough_create_info = {
+		XR_TYPE_PASSTHROUGH_CREATE_INFO_FB,
+		nullptr,
+		0,
+	};
+	XrPassthroughFB passthrough_handle = XR_NULL_HANDLE;
+
+	XrPassthroughLayerCreateInfoFB passthrough_layer_config = {
+		XR_TYPE_PASSTHROUGH_LAYER_CREATE_INFO_FB,
+		nullptr,
+		passthrough_handle,
+		XR_PASSTHROUGH_IS_RUNNING_AT_CREATION_BIT_FB,
+		XR_PASSTHROUGH_LAYER_PURPOSE_RECONSTRUCTION_FB,
+	};
+	XrPassthroughStyleFB passthrough_layer_style = {
+		XR_TYPE_PASSTHROUGH_STYLE_FB,
+		nullptr,
+		1,
+		{ 0, 0, 0, 0 },
+	};
+	XrPassthroughLayerFB passthrough_layer = XR_NULL_HANDLE;
+
+	XrCompositionLayerPassthroughFB composition_passthrough_layer = {
+		XR_TYPE_COMPOSITION_LAYER_PASSTHROUGH_FB,
+		nullptr,
+		XR_COMPOSITION_LAYER_BLEND_TEXTURE_SOURCE_ALPHA_BIT,
+		XR_NULL_HANDLE,
+		XR_NULL_HANDLE,
+	};
+};
+
+#endif // OPENXR_FB_PASSTHROUGH_EXTENSION_WRAPPER_H