ccpr: Implement stroking with fine triangle strips
Implements strokes by linearizing the curve into fine triangle strips
and interpolating a coverage ramp for edge AA. Each triangle in the
strip emits either positive or negative coverage, depending on its
winding direction. Joins and caps are drawn with the existing CCPR
shaders for triangles and conics.
Conic strokes and non-rigid-body transforms are not yet supported.
Bug: skia:
Change-Id: I45a819abd64e91c2b62e992587eb85c703e09e77
Reviewed-on: https://skia-review.googlesource.com/148243
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Allan MacKinnon <allanmac@google.com>
27 files changed