Remove GLFW dependency for non-GL tests

As part of enabling WebGPU on Chrome OS, we would like to run the Dawn
unit and e2e tests as part of the Chrome OS test suite. This CL removes
the GLFW dependency because Chrome OS does not support GLFW.

The GLFWwindow is only used to create swap chains for the various
backends, but these swap chains are not actually used in the tests
(the e2e tests render to textures instead). The swap chains are only
referenced as part of an unused debugging function:
SwapBuffersForCapture which we can safely remove as per my discussions
with kainino@ and enga@.

We still need GLFW for OpenGL, so we conditionally include it on
platforms that enable the OpenGL backend (which Chrome OS is not).

Note: enga@ suggested to create a VulkanWindowlessBinding that has an
empty GetSwapChainImplementation, but after exploring the option, it
seems like a bit too many ifdefs. In the end, I think it's cleaner to
just remove the *Binding classes entirely.

BUG=chromium:993457
TEST=tests compile and pass for all values of dawn_enable_opengl

Change-Id: I067b12a23f2c236f5506252cd7727b847e79a667
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/10080
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Brian Ho <hob@chromium.org>
3 files changed
tree: 0e9750ee6801204ffda720d3db44b5c46ba0a3e1
  1. build_overrides/
  2. docs/
  3. examples/
  4. generator/
  5. infra/
  6. scripts/
  7. src/
  8. third_party/
  9. .clang-format
  10. .gitattributes
  11. .gitignore
  12. .gn
  13. AUTHORS
  14. BUILD.gn
  15. codereview.settings
  16. CONTRIBUTING.md
  17. dawn.json
  18. dawn_wire.json
  19. DEPS
  20. LICENSE
  21. OWNERS
  22. PRESUBMIT.py
  23. README.chromium
  24. README.md
README.md

Dawn, a WebGPU implementation

Dawn (formerly NXT) is an open-source and cross-platform implementation of the work-in-progress WebGPU standard. It exposes a C/C++ API that maps almost one-to-one to the WebGPU IDL and can be managed as part of a larger system such as a Web browser.

Dawn provides several WebGPU building blocks:

  • WebGPU C/C++ headers that applications and other building blocks use.
  • A “native” implementation of WebGPU using platforms' GPU APIs:
    • D3D12 on Windows 10
    • Metal on OSX (and eventually iOS)
    • Vulkan on Windows, Linux (eventually ChromeOS and Android too)
    • OpenGL as best effort where available
  • A client-server implementation of WebGPU for applications that are in a sandbox without access to native drivers

Directory structure

  • dawn.json: description of the API used to drive code generators.
  • examples: examples showing how Dawn is used.
  • generator: code generator for files produces from dawn.json
    • templates: Jinja2 templates for the generator
  • scripts: scripts to support things like continuous testing, build files, etc.
  • src:
    • common: helper code shared between core Dawn libraries and tests/samples
    • dawn_native: native implementation of WebGPU, one subfolder per backend
    • dawn_wire: client-server implementation of WebGPU
    • include: public headers for Dawn
    • tests: internal Dawn tests
      • end2end: WebGPU tests performing GPU operations
      • unittests: unittests and by extension tests not using the GPU
        • validation: WebGPU validation tests not using the GPU (frontend tests)
    • utils: helper code to use Dawn used by tests and samples
  • third_party: directory where dependencies live as well as their buildfiles.

Building Dawn

Dawn uses the Chromium build system and dependency management so you need to install depot_tools and add it to the PATH.

On Linux you need to have the pkg-config command:

# Install pkg-config on Ubuntu
sudo apt-get install pkg-config

Then get the source as follows:

# Clone the repo as "dawn"
git clone https://dawn.googlesource.com/dawn dawn && cd dawn

# Bootstrap the gclient configuration
cp scripts/standalone.gclient .gclient

# Fetch external dependencies and toolchains with gclient
gclient sync

Then generate build files using gn args out/Debug or gn args out/Release. A text editor will appear asking build options, the most common option is is_debug=true/false; otherwise gn args out/Release --list shows all the possible options.

Then use ninja -C out/Release to build dawn and for example ./out/Release/dawn_end2end_tests to run the tests.

Contributing

Please read and follow CONTRIBUTING.md. Dawn doesn‘t have a formal coding style yet, except what’s defined by our clang format style. Overall try to use the same style and convention as code around your change.

If you find issues with Dawn, please feel free to report them on the bug tracker. For other discussions, please post to Dawn's mailing list.

License

Please see LICENSE.

Disclaimer

This is not an officially supported Google product.