68f2c10cdf
This was added in https://chromium-review.googlesource.com/c/angle/angle/+/2181450/30 to support the case where a program fails to relink, but needs to still be usable. However, this does not seem to be an issue anymore. New tests are specifically added for this, and they, along with every other test, pass. If this needs to be reintroduced, it needs to be rethought. It does not play well with parallel link as it changes the executable pointer while link is in progress (and it was done on the assumption that everything needing the executable is linked serially). A better solution would likely be an `mLastSuccessfullyLinkedExecutable` that normally points to `mExecutable`, but not during link. On `resolveLink`, it would either make `mExecutable` point back to `mLastSuccessfullyLinkedExecutable`, or the other way around based on whether the link was successful or not. Bug: angleproject:8297 Change-Id: Ic9d55bccb75fff0253fe299a244bf1e4bbc416a6 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4781632 Reviewed-by: Yuxin Hu <yuxinhu@google.com> Auto-Submit: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Charlie Lao <cclao@google.com>
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 9 | Direct3D 11 | Desktop GL | GL ES | Vulkan | Metal | |
|---|---|---|---|---|---|---|
| OpenGL ES 2.0 | complete | complete | complete | complete | complete | complete |
| OpenGL ES 3.0 | complete | complete | complete | complete | complete | |
| OpenGL ES 3.1 | incomplete | complete | complete | complete | ||
| OpenGL ES 3.2 | in progress | in progress | in progress |
Additionally, OpenGL ES 1.1 is implemented in the front-end using OpenGL ES 3.0 features. This version of the specification is thus supported on all platforms specified above that support OpenGL ES 3.0 with known issues.
Platform support via backing renderers
| Direct3D 9 | Direct3D 11 | Desktop GL | GL ES | Vulkan | Metal | |
|---|---|---|---|---|---|---|
| Windows | complete | complete | complete | complete | complete | |
| Linux | complete | complete | ||||
| Mac OS X | complete | complete [1] | ||||
| iOS | complete [2] | |||||
| Chrome OS | complete | planned | ||||
| Android | complete | complete | ||||
| GGP (Stadia) | complete | |||||
| Fuchsia | complete |
[1] Metal is supported on macOS 10.14+
[2] Metal is supported on iOS 12+
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 1.5 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
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Join our Google group to keep up to date.
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Join us on Slack in the #angle channel. You can follow the instructions on the Chromium developer page for the steps to join the Slack channel. For Googlers, please follow the instructions on this document to use your google or chromium email to join the Slack channel.
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File bugs in the issue tracker (preferably with an isolated test-case).
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Choose an ANGLE branch to track in your own project.
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Read ANGLE development documentation.
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Become a code contributor.
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Use ANGLE's coding standard.
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Learn how to build ANGLE for Chromium development.
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Get help on debugging ANGLE.
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Go through ANGLE's orientation and sift through starter projects. If you decide to take on any task, write a comment so you can get in touch with us, and more importantly, set yourself as the "owner" of the bug. This avoids having multiple people accidentally working on the same issue.
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Read about WebGL on the Khronos WebGL Wiki.
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Learn about the initial ANGLE implementation details in the OpenGL Insights chapter on ANGLE (this is not the most up-to-date ANGLE implementation details, it is listed here for historical reference only) and this ANGLE presentation.
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Learn about the past, present, and future of the ANGLE implementation in this presentation.
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Watch a short presentation on the Vulkan back-end.
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Track the dEQP test conformance
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Read design docs on the Vulkan back-end
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Read about ANGLE's testing infrastructure
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View information on ANGLE's supported extensions
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If you use ANGLE in your own project, we'd love to hear about it!