Vulkan: Fix draw with emulated xfb without xfb active

When transform feedback is not active, make sure the code that captures
xfb is not generated, even though it's guarded against with an if.  This
is because no buffer is bound to the capture buffer, and by avoiding
generation of code that references that buffer, SwiftShader will not
attempt to access the missing descriptor set.

Currently, the actual declaration of the buffer is left in the SPIR-V,
which seems to be benign.  If that causes issues in the future, the
SPIR-V transformer can be modified to remove that variable as well.

Bug: chromium:1209285
Change-Id: I83da8d1dea5390ecacc681f8ada9f586932deaa4
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3294661
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
4 files changed
tree: 12e1f34d76be0683b1ce170d297db56d804c60ba
  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