swung0x48
3e3405e3a8
The indexed and indirect client-memory upload added by 62bfe461 landed inside
`#if MOBILEGL_BUILD_DISAGGREGATED`, and that guard was wrong in the one way a
guard can be wrong without a test saying so: the code exists FOR the monolith
arm - every entry point in the family early-returns when `MG_Config::Transport
!= Monolith` - and the monolith arm is what the pull, verify and push builds
run, not a split-arm fallback. Only the split lane was building the change, so
only the split lane could compile it.
Both CI jobs that build without MOBILEGL_BUILD_DISAGGREGATED were red on the
same twenty diagnostics: `build explicit pull runtime control` (the pull
library retrace's monolith control measures) and `build-linux-verify`
(MOBILEGL_PIPE_VERIFY=ON). DirectGLES.cpp:8437/8455/8521/8537 are the two
indirect executors and :9225/9251/9623/9637/9675/9700 the indexed family,
every one of them in an entry point that compiles in all four flavors, calling
names the pull build had no declaration for:
error: no member named 'SyncClientSideVertexArraysForIndirectFetch' in
namespace 'MobileGL::MG_Backend::DirectGLES::VertexArrayImpl'
... and SyncClientSideVertexArraysForIndexedFetch, likewise.
The block moves out of the guard rather than being duplicated per flavor, so
the split build's preprocessed text and behaviour are unchanged: the three
wrappers keep their `Transport != Monolith` early return, and in the
transport-free flavors that comparison folds to a compile-time false
(Config.h:566) exactly as it does in every other monolith-only body in this
file.
What the guard also covered, and moves with it:
* ClientFetchPlan.h - no longer behind `MOBILEGL_BUILD_DISAGGREGATED &&
MOBILEGL_PIPE_PUSH`. The plan IS the monolith arm's arithmetic (the file's
own header says so: "the monolith arm asks it to size the per-draw upload"),
so a pull build that cannot see it cannot answer the question.
* BackendVertexArrayObject::SyncClientSideAttributesForDraw - declaration and
definition, the callee of SyncClientSideVertexArraysForFetch.
* The `#include <MG_Impl/Pipe/ClientFetchPlan.h>` in Managers.h, which had
been inside the same `#if MOBILEGL_PIPE_PUSH` as the two P3a/P4a includes
it was appended to.
G1: the three wrappers and the byte reader take internal linkage (`static`),
the spelling the sibling SyncClientSideVertexArraysForDrawArrays already uses
at DirectGLES.cpp:2422 for exactly this reason. Verified on the pull build
(Release/INFO, LTO off, library target only, the monolith-symbol-report job's
own flags): 0 added / 0 removed / 0 resized / 0 renamed, .text +0, and every
one of the new names is LOCAL (`t`/`b`) with 0 of them in the dynamic table.
Had they kept external linkage they would have been 0 in the pull symbol delta
anyway (CXX_VISIBILITY_PRESET hidden) and 4 in a Debug build's dynamic table,
which is the configuration CMakeLists.txt:629-641 switches to `default`.
Verified: build-pull rc=0, build-push rc=0, build-verify
(MOBILEGL_PIPE_VERIFY=ON, DISAGGREGATED=OFF) rc=0, build-split rc=0; split
regressions green under both MOBILEGL_TRANSPORT=monolith and =inproc for
ClientVertexArrayScenario (18/18 each) and DrawRangeElements|MultiDraw (119/119
each), so the client-array behaviour 62bfe461..cb64b62b repaired is not
regressed.
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.