Speed up handling of "bowtie" joins in the hw tessellator

Bowtie joins are only used on internal chops, and in that case, they
are only needed on cusps. Rather than measuring the angle to see if we
need the bowtie, we can just detect if the chop was at a cusp instead.

Bug: chromium:1172543
Change-Id: I5efe4df1fb10dd850b65e0f85415d7791e196cd3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/373797
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
1 file changed