Commit bc447ca469c5801d0101539566b537c625eaed79
2022-09-20T22:38:16
GLES1: Move lighting to vertex shader In the spec, lighting is done as part of vertex processing, and results in a new vertex color. Texturing is applied later. ANGLE however did lighting in the fragment shader. With this change, lighting is moved to the vertex shader. This fixes rendering of lit objects, as interpolation is done linearly or flat between the vertices per spec, instead of done precisely per fragment. While typically this is inferior to per-fragment lighting, it's what the spec mandates. On the dr_driving trace, this reduces the render pass time by ~20% on Pixel 6. Bug: angleproject:6201 Bug: angleproject:6644 Change-Id: I10e37df8c56c22d520a738af8f8630bc6a01ca7f Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3906394 Reviewed-by: Constantine Shablya <constantine.shablya@collabora.com> Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>