This definitely simplifies the drawing code, but always copies the input
SkPaint so that it can be modified if necessary. If we get perf hits, we
can just revert this. We could keep it using a copy-on-write, but with
this change, I believe we've removed the majority of instances of
SkCopyOnWrite<SkPaint> inside SkCanvas. There's just one LatticePaint
struct that's overly complex for what it does that I can clean up next.
A middle ground would be to keep the copy-on-write behavior, but drop
the branch on image-filter. Given the lack of perf needle movement on
some of the other simplifications that avoided technically unnecessary
paint copies, I doubt it's worth the complexity.
As part of this change, since the draw calls no longer branch based on
the presence of an image filter, the AutoLayerForImageFilter takes over
calling predrawNotify() in its various forms. We don't have to follow
through with that, if we'd rather have the notification be called out
explicitly within the draw call itself. I've found it easy to forget to
call predrawNotify(), or keep it in the right place while updating draws
so I may be biased.
Bug: skia:10987
Change-Id: I5204c175aae691f82cc45f3d9a04ef64dee5d80f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/342920
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
887ac49f9e