Ground Station port of esp32-cam-fpv for Oculus Quest 2 / 3 / Pro. Renders the FPV stream and full GS UI into a head-locked OpenXR quad layer.

• Standalone Android (Quest) app project
• Kotlin + Compose app shell (no on-screen Compose content; all visuals are the OpenXR layer)
• NDK/CMake native library shared with the legacy android_gs/ build
• Reusable GS core (components_gs/) linked in
• Minimum Android version: 10 (API 29) — Quest 2 baseline
• Compile/target SDK: 34

Two GL contexts in the same EGL share group, each on its own thread:

1. OpenXR thread (openxr_quest_runtime.cpp)

   • Owns the EGL context (master). Publishes it to the bridge on init.
   • Drives the xrWaitFrame / xrBeginFrame / xrEndFrame loop at headset refresh rate.
   • Each frame samples the renderer's offscreen color texture into a 1280×720 XrCompositionLayerQuad swapchain (head-locked, VIEW reference space).
   • Reads controllers via the OpenXR action system: A→ImGuiKey_G, B→ImGuiKey_R, index trigger / thumbstick-click→ImGuiKey_Enter, thumbstick directions→arrow keys. Results are pushed into a small queue in the bridge.

2. Renderer thread (shared GsVideoRenderer from components_gs/shared/)

   • Owns a tiny pbuffer EGL surface in the OpenXR thread's share group (created in android_surface_backend_openxr.cpp). The pbuffer is just a placeholder for eglMakeCurrent; nothing is ever drawn to it.
   • Renders FPV video + ImGui overlays into a 1280×720 offscreen FBO whose color texture is shared with the OpenXR thread (no glReadPixels, no eglSwapBuffers).
   • Drains controller-derived ImGui keys from the bridge each tick via the weak extern gsTryConsumeXrImGuiKey().
   • Caps idle wait at 50 ms (m_cv.wait_for(50ms)) so the menu animates and queued key presses surface within ~50 ms even with no incoming video.

3. Bridge (openxr_video_bridge.cpp)

   • Thread-safe glue: shared EGLContext, renderer's color texture id + dims, controller-key queue.
   • Exposes weak C-linkage hooks (gsGetSharedEglContext, gsPublishRendererTexture, gsTryConsumeXrImGuiKey) so the shared renderer can detect "we're on Quest" and route through the bridge without depending on Quest-specific headers.

There is no Android SurfaceView, no SurfaceFlinger interaction, no CPU buffer round-trip. The user only ever sees the OpenXR composition layer.

The mappings live in syncControllerInputs() in openxr_quest_runtime.cpp. Bindings are declared for /interaction_profiles/oculus/touch_controller. The app does not require a controller — input also reaches the GS via MCP and any other paths the shared renderer supports.

• build.bat — builds the debug APK.
• install.bat — installs the current debug APK to the primary user.
• deploy.bat — force-stops, rebuilds, installs, launches, and verifies the app is resumed.
• enable_wifi_debugging.bat <QUEST_IP> [PORT] — switches an authorized USB-connected Quest into ADB TCP mode and connects to it over Wi-Fi.
• deploy_wifi.bat <QUEST_IP[:PORT]> — same as deploy.bat against a specific Quest Wi-Fi ADB target.

See app/src/main/cpp/third_party/:

• openxr/ — Khronos OpenXR loader headers.
• devourer/{src,hal} — RTL8812AU driver (raw broadcast / Wi-Fi scan).
• include/libusb.h + prebuilt/arm64-v8a/libusb1.0.so — USB host access.