1 files changed, 45 insertions, 0 deletions
diff --git a/src/effects/SkXfermodeImageFilter.cpp b/src/effects/SkXfermodeImageFilter.cpp
index f7ce0a3027..ddc5d99b5e 100644
--- a/src/effects/SkXfermodeImageFilter.cpp
+++ b/src/effects/SkXfermodeImageFilter.cpp
@@ -40,6 +40,8 @@ protected:
                                         SkIPoint* offset) const override;
     sk_sp<SkImageFilter> onMakeColorSpace(SkColorSpaceXformer*) const override;
 
+    SkIRect onFilterBounds(const SkIRect&, const SkMatrix&, MapDirection) const override;
+
 #if SK_SUPPORT_GPU
     sk_sp<SkSpecialImage> filterImageGPU(SkSpecialImage* source,
                                          sk_sp<SkSpecialImage> background,
@@ -173,6 +175,49 @@ sk_sp<SkSpecialImage> SkXfermodeImageFilter_Base::onFilterImage(SkSpecialImage*
     return surf->makeImageSnapshot();
 }
 
+SkIRect SkXfermodeImageFilter_Base::onFilterBounds(const SkIRect& src,
+                                                   const SkMatrix& ctm,
+                                                   MapDirection direction) const {
+    if (kReverse_MapDirection == direction) {
+        return SkImageFilter::onFilterBounds(src, ctm, direction);
+    }
+
+    SkASSERT(2 == this->countInputs());
+    auto getBackground = [&]() {
+        return this->getInput(0) ? this->getInput(0)->filterBounds(src, ctm, direction) : src;
+    };
+    auto getForeground = [&]() {
+        return this->getInput(1) ? this->getInput(1)->filterBounds(src, ctm, direction) : src;
+    };
+    switch (fMode) {
+        case SkBlendMode::kClear:
+            return SkIRect::MakeEmpty();
+
+        case SkBlendMode::kSrc:
+        case SkBlendMode::kDstATop:
+            return getForeground();
+
+        case SkBlendMode::kDst:
+        case SkBlendMode::kSrcATop:
+            return getBackground();
+
+        case SkBlendMode::kSrcIn:
+        case SkBlendMode::kDstIn: {
+            auto result = getBackground();
+            if (!result.intersect(getForeground())) {
+                return SkIRect::MakeEmpty();
+            }
+            return result;
+        }
+
+        default: {
+            auto result = getBackground();
+            result.join(getForeground());
+            return result;
+        }
+    }
+}
+
 sk_sp<SkImageFilter> SkXfermodeImageFilter_Base::onMakeColorSpace(SkColorSpaceXformer* xformer)
 const {
     SkASSERT(2 == this->countInputs());