Dart WebGPU

Dart native bindings of the WebGPU graphics API.

Example

https://github.com/brendan-duncan/dartcraft

WARNING: Experimental, Work In Progress

Development is ongoing and there are no guarantees any of it will work properly. The API is also in flux, to make it more Dart-centric and reduce boilerplate code.

Known Issues

• Currently, it only works on Windows and MacOS. Linux, Web, and possibly Flutter will follow.

• GPUWindow currently locks up MacOS.

• Async functions like mapAsync don't work with Dart's await/Future. Dart will currently crash if you try. The WebGPU async functions, mapAsync, createRenderPipelineAsync, and createComputePipelineAsync, take a callback arg that will be called when the async promise resolves. The Dart async Future failures will need to be investigated further.

Building WebGPU Bindings

To update the webgpu bindings, run python build_libwebgpu.py

This will download the required third-party libraries, build them, and generate an updated version of the ffi Dart bindings using ffigen.

Build Requirements

• git
• Python 3.0+
• CMake 3.15+
• Visual Studio / Xcode
• LLVM
  • Windows: run winget install -e --id LLVM.LLVM
  • MacOS: run brew install llvm
  • Linux: run sudo apt-get install libclang-dev

Third Party Libraries

Dart WebGPU uses the following third party libraries:

• Dawn: https://dawn.googlesource.com/dawn
  • This is Google's implementation of WebGPU.
• lib_webgpu: https://github.com/juj/wasm_webgpu
  • This is a wrapper around Dawn that simplifies the API making binding easier.

Debugging Tips

• Build libwebgpu with python build_libwebgpu.py
• Make sure to load the Debug build of the library by adding initializeWebGPU(config: WGpuConfig.debug); to the top of the Dart program. You can also link against the release-with-debug-info build using initializeWebGPU(config: WGpuConfig.releaseDebug);.
• Add a breakpoint to the Dart code, run in debugger, pausing execution at the breakpoint.
• Open libwebgpu/_build/Debug/libwebgpu.sln in Visual Studio
• In VS Debug / Attach To Process...
  • Find the dart.exe process that has the dart program as an argument.
  • Open the lib_webgpu or Dawn cpp file you want to debug in VS, add a breakpoint to the line you want to catch with the debugger.
  • Unpause the Dart Debugger