https://www.w3.org/TR/SVG11/masking.html#Masking
Implement masking based on a classic two-layers + kSrcIn blending
approach.
An additional layer is used to filter the mask content (but could be
avoided in a pinch -- see inline comments).
Also consolidate the objectBoundingBox rect resolution logic as
SkSVGRenderContext::resolveOBBRect().
Bug: skia:10842
Change-Id: I273318e97cc28d599d1ecf01706b6117eecb62d5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/353631
Commit-Queue: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Tyler Denniston <tdenniston@google.com>
Introduce SkSVGMask and plumb related attributes.
Also consolidate the clip/mask/filter property types - they all support
the same values: <funciri>|none|inherit.
Bug: skia:10842
Change-Id: If45a75cccc19b84d6547237336fe5d562a85d594
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/353436
Commit-Queue: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Tyler Denniston <tdenniston@google.com>
