GrTessellator: fix for ping-pong split fuzzer hang.

Change 3b5a3fa8b1c11d4bd4499b040311f4c3553ebf8c introduced support for
splitting on out-of-range intersections. However, this is only necessary
for correctness when the edge is nearly-flat (the top and bottom
points only differ by 1/2 machine epsilon in the primary sort criterion).
In other cases, it can cause repeated splitting and re-merging of edges,
as the intersection code (being approximate and not exact) may produce a
ping-pong set of intersections.

The fix is to support out-of-range intersections only if they differ by
1/2 machine epsilon. This also generalizes the
out_of_range_and_collinear() check, so it was removed.

Bug: 838978
Change-Id: I134f7eff3f15707e0d68de11c55f7fadce4ff8e7
Reviewed-on: https://skia-review.googlesource.com/130448
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>

0 files changed, 0 insertions, 0 deletions