OpenRA.DirectGLES, transport=spawn, on a Redmi: ssim=1.000000,
mismatchPixels=0, zero Fatal{ lines, three runs for three. The server is a
process the client launched out of the APK's lib/arm64/, and the client's own
log names its pid.
Four things stood between the desktop green and the device green, and every
one of them was invisible on desktop for the same reason: a build tree is not
a deployment, and Linux is not Android.
1. THE SERVER COULD NOT LINK. It links libMobileGL.so and is EXEC'd, not
dlopen'd, so it gets a fresh linker namespace with the DEFAULT search path
- and an APK's lib/<abi>/ is not on it. `CANNOT LINK EXECUTABLE ...:
library "libMobileGL.so" not found: needed by main executable`, before a
single line of MobileGL ran. On desktop CMake had been giving the target an
absolute build-tree RPATH, so the WSL server resolved its dependency
through a path no phone has. $ORIGIN is asked for via BUILD_RPATH (a raw
-Wl,-rpath,$ORIGIN reaches the generator unquoted and the SHELL eats it -
the device linker said `normalize_path - invalid input: "$"`), and because
the NDK drops RPATH from the link anyway, the LAUNCHER states
LD_LIBRARY_PATH: it is the one component that has already resolved where
the image lives, and a pair that is not co-located is not a pair.
2. THE RENDEZVOUS NEEDED A WRITABLE DIRECTORY. An Android app has no /tmp, so
bind() in the child had nowhere to put the node and the client refused by
name 20 s later. AF_UNIX endpoints now accept the ABSTRACT namespace with a
leading '@' - the systemd/D-Bus convention - which has no filesystem
presence at all: no directory, no mode bits, and no stale node to unlink
after a crash, which is the bind() failure Listen() has been working
around. Its reach is the network namespace, which for an app is the app.
StartSpawned mints '@' names; an explicit path still works everywhere, and
that is what P12's "connect to something somebody else is listening on"
will use.
3. PBUFFER WAS A DirectGLES-ONLY KNOB. Twice over: trace-replay-ci.sh gated
`--ez use_pbuffer true` on the backend name, and the JNI demanded a native
window for DirectVulkan unconditionally. A surface SHAPE is not a backend
property, and the coupling mattered because the Android GLWS makes a window
surface whenever gNativeWindow is non-null - so handing Magma a window was
the same as asking for one. Until P12 a spawned server cannot be given a
window at all: an ANativeWindow* is a pointer into the CLIENT's process and
SetWindowHandle is refused on the way across with Fatal{UnmigratedSurface,
"AndroidNativeWindow@P12"} (Rule H). Which is exactly what happened, one op
after the server had come up green.
4. THE RUNNER LOOKED IN ONE OF THE TWO OUTPUT DIRECTORIES. assembleTraceRelease
writes apk/trace/release; CI has staged the same artifact under
apk/trace/debug. A tree that has built locally has both, and picking the
wrong one retraces last month's APK and says nothing about it. Newest of
either, now.
MEASURED AND NOT FIXED: DirectVulkan on this device diverges under BOTH split
transports and does so nondeterministically - inproc scored ssim=0.988998 /
9836 px, spawn scored 0.976494 / 14658 px and then 0.988998 / 9836 px on a
repeat, while monolith with the same pbuffer surface scores 1.000000 / 0 px.
The two transports draw from the same set of outcomes, so this is the split
path on Magma against a real GPU, not the process boundary: P6 neither caused
it nor can fix it. DirectVulkan spawn IS green on desktop (lavapipe, 1.000000).
G14: one test name added, AnAbstractEndpointNeedsNoWritableDirectoryAndLeaves-
NoFile, which pins both halves - the handshake crosses an abstract name, and
nothing is left on the filesystem. A '@' mistaken for a path would have bound
a file of that literal name, passed here, and failed on the one platform this
exists for.
MobileGL
A desktop OpenGL implementation
MobileGL is a free and open-source project that implements a desktop OpenGL API. The goal is to provide a complete desktop OpenGL implementation with a state management layer and multi-backend support.
Note
Status: In development. Parts of the codebase are incomplete. Current short-term target: OpenGL 4.2 (Core Profile).
Project positioning
MobileGL is an implementation of a desktop OpenGL library. It aims to provide:
- Full OpenGL state management.
- A front-end that exposes OpenGL functions.
- Multiple independent backend implementations, where each backend targets a specific graphics API and remains fully isolated from others.
This project is intended as an implementation/translation layer.
Key components
The repository is organized into following top-level modules:
- MG_State — state tracking and management logic for Graphics APIs.
- MG_Impl — front-end implementations of Graphics APIs that interact with
MG_StateandMG_Backend. - MG_Backend — per-backend translation layer that maps front-end Graphics APIs' semantics and state into concrete backend API calls (e.g. OpenGL ES, Vulkan).
- MG_Util and other utility modules.
Third-party components
MobileGL reuses several open-source projects:
- SPIRV-Cross by KhronosGroup - Apache License 2.0: github
- glslang by KhronosGroup - Various Licenses: github
- DiligentCore by Diligent Graphics - Apache License 2.0: github
- flat_hash_map by Malte Skarupke - Boost Software License 1.0: github
Refer to each component's repository for exact license texts. Any bundled third-party code in this repository is included under the upstream project's license.
Compatibility & target
- Short-term target:
OpenGL 4.2 (Core Profile). - Current development focus:
- Performance improvement
MG_StateandMG_ImplforOpenGL 4.2 (Core Profile)Direct (Vulkan)backendDirect (OpenGL ES)backend
Build Instructions
We currently provide no releases and no precompiled binaries.
If you want to try the project right now, you’ll need to build it yourself:
-
Clone the repository:
git clone https://github.com/MobileGL-Dev/MobileGL.git -
Initialize and update all submodules recursively:
git submodule update --init --recursive -
Follow glslang’s own documentation for its required initiation.
-
Configure and build the project with CMake:
cmake -B build cmake --build buildor do it in a modern way:
cmake -S . -B build -G Ninja -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ cmake --build buildAlternatively, you can use platform-specific build commands as needed.
Build For macOS
On macOS, MobileGL can be built as a dylib that exposes the normal OpenGL/CGL/NSOpenGL entry points and routes them to the DirectVulkan backend. This is useful for running applications such as Minecraft through their stock GLFW/LWJGL OpenGL path while MobileGL is injected before context creation.
Prerequisites:
- macOS with Clang and Ninja.
- Vulkan loader and MoltenVK installed. With Homebrew, the MoltenVK ICD is commonly located at
/opt/homebrew/etc/vulkan/icd.d/MoltenVK_icd.json.
Configure and build:
cmake -S . -B build-macos-magma \
-G Ninja \
-DCMAKE_BUILD_TYPE=Release \
-DMOBILEGL_BACKEND_TYPE=DirectVulkan \
-DMOBILEGL_BUILD_TEST=OFF \
-DMOBILEGL_BUILD_BENCHMARK=OFF
cmake --build build-macos-magma --target MobileGL -j8
The dylib will be generated at:
build-macos-magma/libMobileGL.dylib
To run Minecraft by MobileGL from a launcher like PrismLauncher, keep the stock LWJGL/GLFW natives and add a wrapper command to the instance settings:
env DYLD_INSERT_LIBRARIES=/absolute/path/to/MobileGL/build-macos-magma/libMobileGL.dylib MOBILEGL_BACKEND_TYPE=DirectVulkan VK_ICD_FILENAMES=/opt/homebrew/etc/vulkan/icd.d/MoltenVK_icd.json
Also make sure the JVM arguments include:
-XstartOnFirstThread
DYLD_INSERT_LIBRARIES must be active before GLFW creates its OpenGL context. After startup, the Minecraft F3 screen should report MobileGL and the Direct (Vulkan) backend if the injection worked.
Build Options
| Option | Description | Default |
|---|---|---|
MOBILEGL_BUILD_TEST |
Build MobileGL tests (requires Clang) | ON |
MOBILEGL_BUILD_BENCHMARK |
Build MobileGL benchmarks (requires Clang) | ON |
MOBILEGL_FORCE_RELEASE_OPT |
Enable O3 and LTO in Debug build | ON |
MOBILEGL_ENABLE_TRACY |
Enable Tracy profiler for performance analysis | OFF |
Notes:
- The project requires C++23.
MG_TestandMG_Benchmarkcan only be built with Clang, not GCC. To enforce Clang, add-DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++to your command.- On Android, tests and benchmarks are always disabled.
Environment Variables
MobileGL supports runtime configuration via environment variables.
Supported Keys
| Variable | Description | Allowed Values | Default |
|---|---|---|---|
MOBILEGL_BACKEND_TYPE |
Select active backend implementation at startup. | DirectGLES, DirectVulkan |
DirectGLES |
MOBILEGL_DISABLE_TIMERQUERY |
Disable GPU timer-query exposure and use. | 0, 1 |
0 |
MOBILEGL_ESPRYT_USE_ANGLE |
Load ANGLE EGL/GLES libraries. | 0, 1 |
0 |
MOBILEGL_MAGMA_DISABLE_SUBGROUP |
Disable Vulkan shader subgroup support. | 0, 1 |
0 |
MOBILEGL_ADVERTISE_FP64 |
Advertise GL_ARB_gpu_shader_fp64. GLSL double/dvec/dmat compile and run either way - they are narrowed to 32 bits - so this only changes whether an application is told it has 64-bit precision, which it does not. |
0, 1 |
0 |
MOBILEGL_MAGMA_R11G11B10F_FALLBACK |
Use Magma's R11G11B10F format fallback. | 0, 1 |
0 |
MOBILEGL_MAGMA_FRAMESINFLIGHT |
Set Magma frames in flight. | Integer 1–64 |
3 |
MOBILEGL_ESPRYT_AVOID_SAMPLER_MIPMAP_MIN_FILTER |
Avoid sampler mipmap minification filters. | 0, 1 |
0 |
MOBILEGL_COHERENT_AS_FLUSH |
Treat persistent GL_MAP_FLUSH_EXPLICIT_BIT maps as coherent (app-compat for engines like Flywheel that never flush them). |
0, 1 |
0 |
MOBILEGL_ESPRYT_FORCE_DS_READBACK_EMULATION |
Always emulate depth/stencil glReadPixels/glGetTexImage by shader sampling on Espryt, instead of using the driver's own depth/stencil readback where it has one. |
0, 1 |
0 |
VK_ICD_FILENAMES |
Select the Vulkan ICD used by the Vulkan loader. | Path to an ICD JSON file | Loader default |
License
This project is distributed under GNU LGPL v3.0. See the LICENSE file in the repository for detailed information.