Implement cc::FilterOperations::MapRect.

cc/output/filter_operations_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stddef.h>
 
 #include "cc/output/filter_operations.h"
 #include "skia/ext/refptr.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/skia/include/effects/SkBlurImageFilter.h"
 #include "third_party/skia/include/effects/SkDropShadowImageFilter.h"
 #include "ui/gfx/geometry/point.h"
+#include "ui/gfx/geometry/rect.h"
 
 namespace cc {
 namespace {
 
 TEST(FilterOperationsTest, GetOutsetsBlur) {
   FilterOperations ops;
   ops.Append(FilterOperation::CreateBlurFilter(20));
   int top, right, bottom, left;
   top = right = bottom = left = 0;
   ops.GetOutsets(&top, &right, &bottom, &left);
   EXPECT_EQ(57, top);
   EXPECT_EQ(57, right);
   EXPECT_EQ(57, bottom);
   EXPECT_EQ(57, left);
 }
 
+TEST(FilterOperationsTest, MapRectBlur) {
+  FilterOperations ops;
+  ops.Append(FilterOperation::CreateBlurFilter(20));
+  EXPECT_EQ(gfx::Rect(-57, -57, 124, 124),
+            ops.MapRect(gfx::Rect(0, 0, 10, 10)));
+}
+
 TEST(FilterOperationsTest, GetOutsetsDropShadowReferenceFilter) {
   // TODO(hendrikw): We need to make outsets for reference filters be in line
   // with non-reference filters. See crbug.com/523534
   skia::RefPtr<SkImageFilter> filter =
       skia::AdoptRef(SkDropShadowImageFilter::Create(
           SkIntToScalar(3), SkIntToScalar(8), SkIntToScalar(4),
           SkIntToScalar(9), SK_ColorBLACK,
           SkDropShadowImageFilter::kDrawShadowAndForeground_ShadowMode));
   FilterOperations ops;
   ops.Append(FilterOperation::CreateReferenceFilter(filter));
 
   int top, right, bottom, left;
   top = right = bottom = left = 0;
   ops.GetOutsets(&top, &right, &bottom, &left);
   EXPECT_EQ(35, top);
   EXPECT_EQ(9, right);
   EXPECT_EQ(19, bottom);
   EXPECT_EQ(15, left);
 }
 
+TEST(FilterOperationsTest, MapRectDropShadowReferenceFilter) {
+  // TODO(hendrikw): We need to make outsets for reference filters be in line

[Stephen White, 2016/04/11 18:05:00]

Is this comment still valid? If not, remove it.

[jbroman, 2016/04/11 20:21:52]

I'm not entirely clear on what it means, so I figured I'd better not let it get
removed.

[Stephen White, 2016/04/11 20:56:04]

The referenced bug is basically what you're doing here: use real rect mapping,
not outsets (see my comment#2 on that bug). So I think you can remove it from
this flavour of the test.

[jbroman, 2016/04/12 19:32:36]

Done.

+  // with non-reference filters. See crbug.com/523534
+  skia::RefPtr<SkImageFilter> filter =
+      skia::AdoptRef(SkDropShadowImageFilter::Create(
+          SkIntToScalar(3), SkIntToScalar(8), SkIntToScalar(4),
+          SkIntToScalar(9), SK_ColorBLACK,
+          SkDropShadowImageFilter::kDrawShadowAndForeground_ShadowMode));
+  FilterOperations ops;
+  ops.Append(FilterOperation::CreateReferenceFilter(filter));
+  EXPECT_EQ(gfx::Rect(-15, -35, 34, 64), ops.MapRect(gfx::Rect(0, 0, 10, 10)));

[Stephen White, 2016/04/11 18:05:00]

This does look like a reverse mapping. Maybe the code was wrong?

[jbroman, 2016/04/11 20:21:52]

These expectations were taken from GetOutsets (with conversion to a rectangle).
See previous comment.

[Stephen White, 2016/04/11 20:56:04]

Yeah, I think there is/was a bug in GetOutsets().

[jbroman, 2016/04/12 19:32:37]

Acknowledged.

+}
+
 TEST(FilterOperationsTest, GetOutsetsNullReferenceFilter) {
   FilterOperations ops;
   ops.Append(FilterOperation::CreateReferenceFilter(nullptr));
 
   int top, right, bottom, left;
   top = right = bottom = left = 0;
   ops.GetOutsets(&top, &right, &bottom, &left);
   EXPECT_EQ(0, top);
   EXPECT_EQ(0, right);
   EXPECT_EQ(0, bottom);
   EXPECT_EQ(0, left);
 }
 
+TEST(FilterOperationsTest, MapRectNullReferenceFilter) {
+  FilterOperations ops;
+  ops.Append(FilterOperation::CreateReferenceFilter(nullptr));
+  EXPECT_EQ(gfx::Rect(0, 0, 10, 10), ops.MapRect(gfx::Rect(0, 0, 10, 10)));

[Stephen White, 2016/04/11 18:05:00]

Could you add a test for a non-null Reference filter, e.g., an
SkOffsetImageFilter?

[jbroman, 2016/04/11 20:21:52]

Is the drop shadow reference filter (above) insufficient? I've mirrored the
existing tests. I'm happy to add one for SkOffsetImageFilter if you think that's
additionally useful.

[Stephen White, 2016/04/11 20:56:04]

The advantage of SkOffsetImageFilter is that it doesn't union with the original
primitive, so it tends to show bugs which don't show up in drop shadow (which
does).

[jbroman, 2016/04/12 19:32:36]

Done.

+}
+
 TEST(FilterOperationsTest, GetOutsetsDropShadow) {
   FilterOperations ops;
   ops.Append(FilterOperation::CreateDropShadowFilter(gfx::Point(3, 8), 20, 0));
   int top, right, bottom, left;
   top = right = bottom = left = 0;
   ops.GetOutsets(&top, &right, &bottom, &left);
   EXPECT_EQ(49, top);
   EXPECT_EQ(60, right);
   EXPECT_EQ(65, bottom);
   EXPECT_EQ(54, left);
 }
 
+TEST(FilterOperationsTest, MapRectDropShadow) {
+  FilterOperations ops;
+  ops.Append(FilterOperation::CreateDropShadowFilter(gfx::Point(3, 8), 20, 0));
+  EXPECT_EQ(gfx::Rect(-54, -49, 124, 124),
+            ops.MapRect(gfx::Rect(0, 0, 10, 10)));
+}
+
 #define SAVE_RESTORE_AMOUNT(filter_name, filter_type, a)                  \
   {                                                                       \
     FilterOperation op = FilterOperation::Create##filter_name##Filter(a); \
     EXPECT_EQ(FilterOperation::filter_type, op.type());                   \
     EXPECT_EQ(a, op.amount());                                            \
                                                                           \
     FilterOperation op2 = FilterOperation::CreateEmptyFilter();           \
     op2.set_type(FilterOperation::filter_type);                           \
                                                                           \
     EXPECT_NE(a, op2.amount());                                           \
@@ skipping 646 matching lines @@
   blended = to.Blend(from, -0.75);
   EXPECT_EQ(to, blended);
   blended = to.Blend(from, 0.75);
   EXPECT_EQ(to, blended);
   blended = to.Blend(from, 1.5);
   EXPECT_EQ(to, blended);
 }
 
 }  // namespace
 }  // namespace cc