Reland "Fix SkImageSource::filterBounds()"

This relands commit cb4d58766668b003fea67798027fc25d84acd059
which was reverted by commit b6d2be1330f16fe05f1eed5abda927c0fbb50055
because the original CL broke some blink layout tests.

This reland let SkImageSource::filterBounds() return the dst rect with
ctm applied regardless of direction.

Original description:

> Previously SkImageSource::filterBounds() uses the default
> SkImageFilter::onFilterNodeBounds() which returns the input rect.
>
> Now override onFilterNodeBounds() in SkImageSource to return src
> or dst rect (with transform applied).

Change-Id: I915b7889ff59829ddbc4479cd66d75a0bb581e54
Reviewed-on: https://skia-review.googlesource.com/47501
Commit-Queue: Stephen White <senorblanco@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>

1 files changed, 44 insertions, 2 deletions

diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index 05c0bffbea..d880a0c814 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -1941,7 +1941,7 @@ DEF_TEST(ImageFilterColorSpaceDAG, reporter) {
     REPORTER_ASSERT(reporter, filter->cloneCount() == 1u);
 }
 
-// Test XfermodeimageFilter::onFilterBounds with different blending modes.
+// Test SkXfermodeImageFilter::filterBounds with different blending modes.
 DEF_TEST(XfermodeImageFilterBounds, reporter) {
     SkIRect background_rect = SkIRect::MakeXYWH(0, 0, 100, 100);
     SkIRect foreground_rect = SkIRect::MakeXYWH(50, 50, 100, 100);
@@ -2049,8 +2049,50 @@ static void test_arithmetic_combinations(skiatest::Reporter* reporter, float v)
     test_arithmetic_bounds(reporter, v, v, v, v, background, foreground, &crop, crop_rect);
 }
 
-// Test ArithmeticImageFilter::onFilterBounds with different blending modes.
+// Test SkArithmeticImageFilter::filterBounds with different blending modes.
 DEF_TEST(ArithmeticImageFilterBounds, reporter) {
     test_arithmetic_combinations(reporter, 1);
     test_arithmetic_combinations(reporter, 0.5);
 }
+
+// Test SkImageSource::filterBounds.
+DEF_TEST(ImageSourceBounds, reporter) {
+    sk_sp<SkImage> image(SkImage::MakeFromBitmap(make_gradient_circle(64, 64)));
+    // Default src and dst rects.
+    sk_sp<SkImageFilter> source1(SkImageSource::Make(image));
+    SkIRect imageBounds = SkIRect::MakeWH(64, 64);
+    SkIRect input(SkIRect::MakeXYWH(10, 20, 30, 40));  // The values don't matter.
+    REPORTER_ASSERT(reporter,
+                    imageBounds == source1->filterBounds(input, SkMatrix::I(),
+                                                         SkImageFilter::kForward_MapDirection));
+    REPORTER_ASSERT(reporter,
+                    imageBounds == source1->filterBounds(input, SkMatrix::I(),
+                                                         SkImageFilter::kReverse_MapDirection));
+    SkMatrix scale(SkMatrix::MakeScale(2));
+    SkIRect scaledBounds = SkIRect::MakeWH(128, 128);
+    REPORTER_ASSERT(reporter,
+                    scaledBounds == source1->filterBounds(input, scale,
+                                                          SkImageFilter::kForward_MapDirection));
+    REPORTER_ASSERT(reporter,
+                    scaledBounds == source1->filterBounds(input, scale,
+                                                          SkImageFilter::kReverse_MapDirection));
+
+    // Specified src and dst rects.
+    SkRect src(SkRect::MakeXYWH(0.5, 0.5, 100.5, 100.5));
+    SkRect dst(SkRect::MakeXYWH(-10.5, -10.5, 120.5, 120.5));
+    sk_sp<SkImageFilter> source2(SkImageSource::Make(image, src, dst, kMedium_SkFilterQuality));
+    REPORTER_ASSERT(reporter,
+                    dst.roundOut() == source2->filterBounds(input, SkMatrix::I(),
+                                                            SkImageFilter::kForward_MapDirection));
+    REPORTER_ASSERT(reporter,
+                    dst.roundOut() == source2->filterBounds(input, SkMatrix::I(),
+                                                            SkImageFilter::kReverse_MapDirection));
+    scale.mapRect(&dst);
+    scale.mapRect(&src);
+    REPORTER_ASSERT(reporter,
+                    dst.roundOut() == source2->filterBounds(input, scale,
+                                                            SkImageFilter::kForward_MapDirection));
+    REPORTER_ASSERT(reporter,
+                    dst.roundOut() == source2->filterBounds(input, scale,
+                                                            SkImageFilter::kReverse_MapDirection));
+}