These files, and several snippets of other files, are generated by Dawn (Chromium's WebGPU library):
The C header is mostly the same as the "upstream"
webgpu.h,
but native-specific elements are not included.
The C++ files are currently Dawn-specific, but included in Emscripten for
better compatibility with Dawn: it has roughly the same API as Dawn's copy, but
is included here because it is strongly tied to an exact webgpu.h revision.
Dawn additionally autogenerates two "snippets" that are used in Emscripten:
library_webgpu_enum_tables.js, which is pasted intolibrary_webgpu.jswebgpu_struct_info.json, which is pasted intostruct_info.json.
Once that's done, you need to update the auto-generated files with the commands below:
./tools/gen_struct_info.py
./tools/gen_struct_info.py --wasm64
./tools/gen_sig_info.py
There is a browser.test_webgpu_basic_rendering with minimal WebGPU API testing that can be handy to test manually before making a contribution.
test/runner browser.test_webgpu_basic_rendering
You may need to specify extra browser cmd args to assign the WebGPU supported browser, which is needed if you work on linux where WebGPU is not enabled by default in chrome at present.
test/runner browser.test_webgpu_basic_rendering --browser="google-chrome-unstable --enable-unsafe-webgpu --enable-features=Vulkan,UseSkiaRenderer"
Alternatively you can test your emscripten updates by building the source file, and then serve (e.g. use node http-server) and view in browser to make sure things work fine.
emcc test/webgpu_basic_rendering.cpp -sUSE_WEBGPU -o path/to/index.html