Commit 3f647b1bf9a476adb1af5037b88ef7403eb73e31

Jamie Madill 2019-11-09T16:24:50

Vulkan: Improve Bresenham line emulation. Clamps the vertex position to the subpixel grid before interpolation. This will give more correct results on systems that have less than 8 bits of subpixel accuracy. Also uses a more accurate formulation for the emulation filter in the fragment shader using dfdx and dfdy. Fixes line raster CTS tests on SwiftShader. Still does not produce spec conformant lines. Updates the public docs to indicate this. Bug: angleproject:2830 Change-Id: Ib9a268df3e7d986bd2b1348be664389fe8fc0ef2 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1826598 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Tim Van Patten <timvp@google.com>