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 | WebGPU |
|---|
| OpenGL ES 2.0 | complete | complete | complete | complete | complete | complete | in progress |
| OpenGL ES 3.0 | | complete | complete | complete | complete | complete | |
| OpenGL ES 3.1 | | | complete | complete | complete | | |
| OpenGL ES 3.2 | | | in progress | in progress | complete | | |
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 | WebGPU |
|---|
| Windows | complete | complete | complete | complete | complete | | |
| Linux | | | complete | | complete | | |
| Mac OS X | | | deprecated | | | complete [1] | |
| iOS | | | | | | complete [2] | |
| Chrome OS | | | | complete | planned | | |
| Android | | | | complete | 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)
- OpenGL ES 3.2: ANGLE 2.1.2.21688.59f158c1695f (Sept, 2023)
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.
OpenCL Implementation
In addition to OpenGL ES, ANGLE also provides an optional OpenCL runtime built into the same
output GLES lib.
This work/effort is currently work-in-progress/experimental.
This work provides the same benefits as the OpenGL implementation, having OpenCL APIs be
translated to other HW-supported APIs available on that platform.
Level of OpenCL support via backing renderers
| Vulkan | OpenCL |
|---|
| OpenCL 1.0 | in progress | in progress |
| OpenCL 1.1 | in progress | in progress |
| OpenCL 1.2 | in progress | in progress |
| OpenCL 3.0 | in progress | in progress |
Each supported backing renderer above ends up being an OpenCL Platform for the user to choose from.
The OpenCL backend is a "passthrough" implementation which does not perform any API translation
at all, instead forwarding API calls to other OpenCL driver(s)/implementation(s).
OpenCL also has an online compiler component to it that is used to compile OpenCL C source code at runtime
(similarly to GLES and GLSL). Depending on the chosen backend(s), compiler implementations may vary. Below is
a list of renderers and what OpenCL C compiler implementation is used for each:
Vulkan : clspvOpenCL : Compiler is part of the native driver
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.
以上为 README 的开头部分。其余内容请阅读原文。 查看完整 README ↗
