support dither in skvm
Dither is handled here by the blitter itself,
when requested and the shader is not constant.
A little refactoring to hang onto the integer (dx,dy)
dst coordinates we need, a little math using them,
and some plumbing to pass around whether or not to
dither and if so how much.
Left another TODO to think about unpremul dither.
Change-Id: Ia660cf12cc729578684233a48088aa703563ecd9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/266362
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
1 file changed