Added Android Meta Quest Support

runtime/include/vr/openxr_backend.h

@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#if defined(MKW_ENABLE_OPENXR)
+
+#include "vr/openxr_runtime.h"
+
+#include <array>
+#include <cstdint>
+
+namespace mkw::vr {
+
+// Backend-neutral frame vocabulary shared by every graphics binding.
+//
+// The OpenXR pacing thread in openxr_integration.cpp is written against these
+// types and the method surface documented on OpenXRD3D12Backend; each concrete
+// backend (D3D12 on Windows, Vulkan on Android) implements that same surface so
+// the pacing, retained-layer and policy logic is compiled once for both.
+
+enum class OpenXRFrameMode {
+    ImmersiveProjection,
+    VirtualScreen,
+};
+
+enum class OpenXRBeginStatus {
+    Ready,
+    SessionNotRunning,
+    ExitRequested,
+    Error,
+};
+
+enum class OpenXRSubmissionStatus {
+    Success,
+    Failed,
+    Timeout,
+    ShuttingDown,
+};
+
+struct OpenXRPresentation {
+    OpenXRFrameMode mode = OpenXRFrameMode::ImmersiveProjection;
+
+    // Used only by VirtualScreen.
+    float quad_distance_meters = 2.0f;
+    float quad_width_meters = 2.4f;
+
+    // When quad_anchored is set, the quad is placed at quad_pose in the
+    // application reference space and stays put as the player looks around.
+    // Otherwise it falls back to being head-locked in XR_VIEW_SPACE, centered
+    // straight ahead at -Z, which is what happens until tracking has produced a
+    // head pose good enough to anchor against.
+    bool quad_anchored = false;
+    XrPosef quad_pose{{0.0f, 0.0f, 0.0f, 1.0f}, {0.0f, 0.0f, 0.0f}};
+};
+
+struct OpenXRBackendFrame {
+    OpenXRFrame xr_frame;
+    OpenXRPresentation presentation;
+    std::array<uint32_t, kOpenXREyeCount> render_width{};
+    std::array<uint32_t, kOpenXREyeCount> render_height{};
+    bool expects_gpu_submission = false;
+};
+
+} // namespace mkw::vr
+
+#endif // defined(MKW_ENABLE_OPENXR)