Support multisampled depth texture bindings

Adds support for processing texture_depth_multisampled_2d bindings
reflected from Tint, and also removes Dawn restrictions against
multisampled depth. These restrictions were originally added in to validate
against using a multisampled depth texture with a
comparison sampler. This is now disallowed by the language with
distinct binding types and builtins in WGSL. Previously with
SPIR-V, we inferred Depth if the texture was used
with a comparison sampler.

Also check Vulkan limits for supported sample counts.

Bug: dawn:1021, dawn:1030
Change-Id: I7233b16c14dc80d10a851cc4e786d5b05512b57a
Reviewed-by: Corentin Wallez <>
Reviewed-by: Jiawei Shao <>
Commit-Queue: Austin Eng <>
5 files changed
tree: c7400e732a927aeef3befd157aa728e79a665b71
  1. .vscode/
  2. build_overrides/
  3. docs/
  4. examples/
  5. generator/
  6. infra/
  7. scripts/
  8. src/
  9. third_party/
  10. tools/
  11. .clang-format
  12. .gitattributes
  13. .gitignore
  14. .gn
  17. CMakeLists.txt
  18. codereview.settings
  19. dawn.json
  20. dawn_wire.json
  21. DEPS
  24. OWNERS
  26. README.chromium

Dawn, a WebGPU implementation

Dawn is an open-source and cross-platform implementation of the work-in-progress WebGPU standard. More precisely it implements webgpu.h that is a one-to-one mapping with the WebGPU IDL. Dawn is meant to be integrated as part of a larger system and is the underlying implementation of WebGPU in Chromium.

Dawn provides several WebGPU building blocks:

  • WebGPU C/C++ headers that applications and other building blocks use.
    • The webgpu.h version that Dawn implements.
    • A C++ wrapper for the webgpu.h.
  • A “native” implementation of WebGPU using platforms' GPU APIs:
    • D3D12 on Windows 10
    • Metal on macOS and iOS
    • Vulkan on Windows, Linux, ChromeOS, Android and Fuchsia
    • OpenGL as best effort where available
  • A client-server implementation of WebGPU for applications that are in a sandbox without access to native drivers

Helpful links:

Documentation table of content

Developer documentation:

User documentation: (TODO, figure out what overlaps with the webgpu.h docs)




Apache 2.0 Public License, please see LICENSE.


This is not an officially supported Google product.