Image filters: Make a recursive, forward-mapping bounds

traversal which respects the CropRect. This is useful when
you want the device-space bounds of a primitive after
filtering. (This may also eventually subsume
computeFastBounds()).

This CL generalizes filterBounds() and onFilterBounds() to
take a mapping direction. It also makes filterBounds()
responsible for calling onFilterNodeBounds() and applying
the crop rect, simplifying onFilterBounds().

BUG=skia:4627
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1612953004

Review URL: https://codereview.chromium.org/1612953004

1 files changed, 2 insertions, 1 deletions

diff --git a/src/effects/SkMergeImageFilter.cpp b/src/effects/SkMergeImageFilter.cpp
index 2ae8b35cd0..12fff9533a 100755
--- a/src/effects/SkMergeImageFilter.cpp
+++ b/src/effects/SkMergeImageFilter.cpp
@@ -92,7 +92,8 @@ bool SkMergeImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
     }
 
     // Apply the crop rect to the union of the inputs' bounds.
-    if (!this->getCropRect().applyTo(bounds, ctx, &bounds)) {
+    this->getCropRect().applyTo(bounds, ctx.ctm(), &bounds);
+    if (!bounds.intersect(ctx.clipBounds())) {
         return false;
     }