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android / platform / external / angle / f9d261f57
commitf9d261f5747c25043be80e97601e586ab1855aa7[log] [tgz]
authorShahbaz Youssefi <syoussefi@chromium.org>Wed Aug 25 10:23:48 2021 -0400
committerAngle LUCI CQ <angle-scoped@luci-project-accounts.iam.gserviceaccount.com>Wed Aug 25 20:24:53 2021 +0000
tree89ab207a7aa323468f027b02d351ee1fc3f38488
parent1fc754b02698ebb28c764392c539fdfb814ae528 [diff]
Translator: Don't promote precision from initializer

Take the following GLSL code:

    precision mediump float;
    uniform highp float u;

    float x = u;

When `x` is declared, its precision is mediump due to
`precision mediump float`.  Its initializer (`u`) however is highp.
Previously, ANGLE generated the following code to ensure the precision
of the initializer is applied to the variable:

    highp float x = u;

Compiling the same code with glslang and looking at the SPIR-V (both
SPIR-V for OpenGL and SPIR-V for Vulkan), such a promotion is not done.
The generated SPIR-V is equivalent to:

    mediump float x = u;

This change aligns ANGLE's output with glslang's by outputting the
precision of the variable itself instead of the precision of the
assignment (which is highp due to promotion from the two operands).

Bug: angleproject:4889
Bug: angleproject:6132
Change-Id: I6f338a865c0a7710329fc13bc171fd245dd30b31
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3118965
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
2 files changed
tree: 89ab207a7aa323468f027b02d351ee1fc3f38488
  1. android/
  2. build_overrides/
  3. doc/
  4. extensions/
  5. gni/
  6. include/
  7. infra/
  8. samples/
  9. scripts/
  10. src/
  11. third_party/
  12. tools/
  13. util/
  14. .clang-format
  15. .gitattributes
  16. .gitignore
  17. .gn
  18. .style.yapf
  19. .vpython
  20. .vpython3
  21. .yapfignore
  22. additional_readme_paths.json
  23. Android.mk
  24. AUTHORS
  25. BUILD.gn
  26. codereview.settings
  27. CONTRIBUTORS
  28. DEPS
  29. DIR_METADATA
  30. dotfile_settings.gni
  31. LICENSE
  32. OWNERS
  33. PRESUBMIT.py
  34. README.chromium
  35. README.md
  36. WATCHLISTS
README.md

ANGLE - Almost Native Graphics Layer Engine

The goal of ANGLE is to allow users of multiple operating systems to seamlessly run WebGL and other OpenGL ES content by translating OpenGL ES API calls to one of the hardware-supported APIs available for that platform. ANGLE currently provides translation from OpenGL ES 2.0, 3.0 and 3.1 to Vulkan, desktop OpenGL, OpenGL ES, Direct3D 9, and Direct3D 11. Future plans include ES 3.2, translation to Metal and MacOS, Chrome OS, and Fuchsia support.

Level of OpenGL ES support via backing renderers

Direct3D 9Direct3D 11Desktop GLGL ESVulkanMetal
OpenGL ES 2.0completecompletecompletecompletecompletecomplete
OpenGL ES 3.0completecompletecompletecompletein progress
OpenGL ES 3.1incompletecompletecompletecomplete
OpenGL ES 3.2in progressin progressin progress

Platform support via backing renderers

Direct3D 9Direct3D 11Desktop GLGL ESVulkanMetal
Windowscompletecompletecompletecompletecomplete
Linuxcompletecomplete
Mac OS Xcompletein progress
iOSplanned
Chrome OScompleteplanned
Androidcompletecomplete
GGP (Stadia)complete
Fuchsiacomplete

ANGLE v1.0.772 was certified compliant by passing the OpenGL ES 2.0.3 conformance tests in October 2011.

ANGLE has received the following certifications with the Vulkan backend:

  • OpenGL ES 2.0: ANGLE 2.1.0.d46e2fb1e341 (Nov, 2019)
  • OpenGL ES 3.0: ANGLE 2.1.0.f18ff947360d (Feb, 2020)
  • OpenGL ES 3.1: ANGLE 2.1.0.f5dace0f1e57 (Jul, 2020)

ANGLE also provides an implementation of the EGL 1.4 specification.

ANGLE is used as the default WebGL backend for both Google Chrome and Mozilla Firefox on Windows platforms. Chrome uses ANGLE for all graphics rendering on Windows, including the accelerated Canvas2D implementation and the Native Client sandbox environment.

Portions of the ANGLE shader compiler are used as a shader validator and translator by WebGL implementations across multiple platforms. It is used on Mac OS X, Linux, and in mobile variants of the browsers. Having one shader validator helps to ensure that a consistent set of GLSL ES shaders are accepted across browsers and platforms. The shader translator can be used to translate shaders to other shading languages, and to optionally apply shader modifications to work around bugs or quirks in the native graphics drivers. The translator targets Desktop GLSL, Vulkan GLSL, Direct3D HLSL, and even ESSL for native GLES2 platforms.

Sources

ANGLE repository is hosted by Chromium project and can be browsed online or cloned with

git clone https://chromium.googlesource.com/angle/angle

Building

View the Dev setup instructions.

Contributing