Revert "Fix several WGL test failures."

This reverts commit 13a8c4d84e16137c47cb2f958b24c08797527cfc.

Reason for revert: Seems to have led to a flakier situation:

Original change's description:
> Fix several WGL test failures.
> SimpleOperationTest.ClearAndSwap/ES2_WGL failed when run in isolation,
> since getGLWindow()->hasError() would report a previous error,
> instead of result of swapBuffers().
> When running after an OPENGL test, swapBuffers() would clear
> the previous error, but that doesn't happen in isolation.
> The previous error is from loading WGL functions, some of which are
> expected not to be present. Clear the error in GetProcAddressWithFallback,
> but verify that there is no error entering it.
> This uncovers more errors in angle_perftests:
> DrawCallPerfBenchmark.Run/wgl
> DrawCallPerfBenchmark.Run/wgl_tex_change
> DrawCallPerfBenchmark.Run/wgl_vbo_change
> DrawElementsPerfBenchmark.Run/wgl_ushort
> They come from redundant calls when destroying a window. Fix this as well.
> Several more errors where uncovered by debug prints, fix those, too.
> Bug: angleproject:3153
> Change-Id: I559c098be9dcdfd3add83f045f745d190250b986
> Reviewed-on:
> Commit-Queue: Yuly Novikov <>
> Reviewed-by: Shahbaz Youssefi <>,,,

Change-Id: I095fadc0dd3a2c998c1dc86f3760184ae6fd7309
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: angleproject:3153
Reviewed-by: Jamie Madill <>
Commit-Queue: Jamie Madill <>
4 files changed
tree: 7cdf0cf4d8e62bcacd0bf28996a73b9169a48c99
  1. .clang-format
  2. .gitattributes
  3. .gitignore
  4. .gn
  8. DEPS
  10. OWNERS
  12. README.chromium
  15. additional_readme_paths.json
  16. android/
  17. build_overrides/
  18. codereview.settings
  19. doc/
  20. dotfile_settings.gni
  21. extensions/
  22. gni/
  23. include/
  24. infra/
  25. samples/
  26. scripts/
  27. src/
  28. third_party/
  29. tools/
  30. util/

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 and 3.0 to desktop OpenGL, OpenGL ES, Direct3D 9, and Direct3D 11. Support for translation from OpenGL ES to Vulkan is underway, and future plans include compute shader support (ES 3.1) and MacOS support.

Level of OpenGL ES support via backing renderers

Direct3D 9Direct3D 11Desktop GLGL ESVulkan
OpenGL ES 2.0completecompletecompletecompletein progress
OpenGL ES 3.0completecompletein progressnot started
OpenGL ES 3.1not startedin progressin progressnot started

Platform support via backing renderers

Direct3D 9Direct3D 11Desktop GLGL ESVulkan
Windowscompletecompletecompletecompletein progress
Linuxcompletein progress
Mac OS Xin progress
Chrome OScompleteplanned
Androidcompletein progress

ANGLE v1.0.772 was certified compliant by passing the ES 2.0.3 conformance tests in October 2011. 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, Direct3D HLSL, and even ESSL for native GLES2 platforms.


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

git clone


View the Dev setup instructions.