GrTessellator: fix intersection above the first vertex.
Handle the case where the an intersection falls not only above both
edge endpoints, but above the first vertex in the mesh. This requires
passing the mesh into check_for_intersection(), in order to modify the
head. We also need to rewind the mesh after insertion, since we need
to rewind to the newly-inserted vertex.
This also cleans up vertex ID computation a little (for logging), so
that vertices before the first vertex or after the last have a
reasonable ID. It also cleans up the intersection-on-endpoint
special cases by refactoring the calls to split_edge().
BUG=730687
Change-Id: Idea736eca7b7c3c5d8a470b1373a16ad8e649e80
Reviewed-on: https://skia-review.googlesource.com/19069
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>
2 files changed