GrTessellator: fix for collinear out-of-range intersections.
Change 3b5a3fa8b1c11d4bd4499b040311f4c3553ebf8c introduced support
for out-of-range intersections, which is necessary when the top and
bottom vertices of an edge differ by only one ULP in the primary sort
order and can't be split in-order.
However, some out-of-range intersections produce edges which cancel
each other out on splitting, in particular when the intersection is
collinear with the newly-computed edge. This undoes the effect of the
split. The tessellator then rewinds, re-detects the intersection, resplits,
an infinite loop.
The fix is to check for out-of-range intersections which are also
collinear, and ignore them. This is ok, because these are not
the cases we care about it change 3b5a3f above, which are
never collinear.
Bug: 753867
Change-Id: I590231e0e6f19c98f1ccf46cb7acc8a63ba35a9d
Reviewed-on: https://skia-review.googlesource.com/34925
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>
2 files changed