SDL_gpu_xr_examples

Cross-platform XR (VR/AR) examples using SDL3's GPU API with OpenXR. Supports desktop VR (SteamVR, Oculus Link) and standalone Quest headsets.

Features

• SDL3 GPU API with Vulkan backend
• OpenXR stereo rendering
• Cross-platform: Desktop (Windows/Linux) and Android (Quest)
• SPIR-V shader loading
• Proper XR view/projection matrix math

Examples

Example	Description
SpinningCubes	Multiple colored cubes spinning in VR space
(more coming)	BasicVr, VrGallery, etc.

Project Structure

SDL_gpu_xr_examples/
├── examples/
│   └── SpinningCubes/
│       └── main.c            # Spinning cubes VR demo
├── shaders/                  # SPIR-V shaders
├── android/                  # Android/Quest build
│   ├── app/
│   │   ├── build.gradle
│   │   └── jni/CMakeLists.txt
│   └── build.gradle
├── CMakeLists.txt            # Desktop build
└── README.md

Building

Prerequisites

Desktop:

• CMake 3.16+
• SDL3 (with OpenXR support)
• OpenXR SDK/runtime (SteamVR, Oculus, etc.)

Android/Quest:

• Android SDK (API 35+)
• Android NDK (27.0.12077973+)
• JDK 11+ (tested with JDK 19)
• Meta Quest in developer mode

Desktop Build

mkdir build && cd build
cmake .. -DSDL3_DIR=/path/to/SDL
cmake --build .
./SpinningCubes

Android/Quest Build

Requires sibling SDL directory:

parent/
├── SDL/                      # Starkium/SDL openxr branch
├── SDL_gpu_examples/         # For shader assets
└── SDL_gpu_xr_examples/      # This project

cd android
$env:JAVA_HOME = "C:\Program Files\Java\jdk-19"
.\gradlew installDebug

Launch on Quest:

adb shell am start -n com.sdl.xr.examples/org.libsdl.app.SDLActivity

Android OpenXR Loader

Uses the Khronos OpenXR loader via Maven:

implementation 'org.khronos.openxr:openxr_loader_for_android:1.1.54'

Note: Do NOT use Meta's forwardloader - it has issues with pre-instance OpenXR calls.

Related Links

• SDL PR #14837 - GPU OpenXR integration
• SDL_gpu_examples - Non-XR GPU examples
• Based on original work by Beyley in SDL PR #11601

License

zlib license (same as SDL)