Initial implementation of GeometryMapper

third_party/WebKit/Source/platform/graphics/paint/GeometryMapperTest.cpp

Index: third_party/WebKit/Source/platform/graphics/paint/GeometryMapperTest.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/paint/GeometryMapperTest.cpp b/third_party/WebKit/Source/platform/graphics/paint/GeometryMapperTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..f71ee303d62aade6e787212e123feaf7e6ab87a9
--- /dev/null
+++ b/third_party/WebKit/Source/platform/graphics/paint/GeometryMapperTest.cpp
@@ -0,0 +1,312 @@
+// Copyright 2016 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 "platform/graphics/paint/GeometryMapper.h"
+
+#include "platform/geometry/GeometryTestHelpers.h"
+#include "platform/geometry/LayoutRect.h"
+#include "platform/graphics/paint/ClipPaintPropertyNode.h"
+#include "platform/graphics/paint/EffectPaintPropertyNode.h"
+#include "platform/graphics/paint/TransformPaintPropertyNode.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+class GeometryMapperTest : public ::testing::Test {
+public:
+    RefPtr<TransformPaintPropertyNode> rootTransformNode;
+    RefPtr<ClipPaintPropertyNode> rootClipNode;
+    RefPtr<EffectPaintPropertyNode> rootEffectNode;
+
+    std::unique_ptr<GeometryMapper> geometryMapper;
+
+    PropertyTreeState rootPropertyTreeState()
+    {
+        PropertyTreeState state(rootTransformNode.get(), rootClipNode.get(), rootEffectNode.get());
+        return state;
+    }
+
+    PrecomputedDataForAncestor& GetPrecomputedDataForAncestor(const PropertyTreeState& propertyTreeState)
+    {
+        return geometryMapper->GetPrecomputedDataForAncestor(propertyTreeState);
+    }
+
+private:
+    void SetUp() override
+    {
+        rootTransformNode = TransformPaintPropertyNode::create(TransformationMatrix(), FloatPoint3D(), nullptr);
+        rootClipNode = ClipPaintPropertyNode::create(rootTransformNode, FloatRoundedRect(LayoutRect::infiniteIntRect()), nullptr);
+        rootEffectNode = EffectPaintPropertyNode::create(1.0, nullptr);
+        geometryMapper = wrapUnique(new GeometryMapper());
+    }
+
+    void TearDown() override
+    {
+        geometryMapper.reset();
+    }
+};
+
+const static float kTestEpsilon = 1e-6;
+
+#define EXPECT_RECT_EQ(expected, actual) \
+do { \
+    const FloatRect& actualRect = actual; \
+    EXPECT_TRUE(GeometryTest::ApproximatelyEqual(expected.x(), actualRect.x(), kTestEpsilon)) << "actual: " << actualRect.x() << ", expected: " << expected.x(); \
+    EXPECT_TRUE(GeometryTest::ApproximatelyEqual(expected.y(), actualRect.y(), kTestEpsilon)) << "actual: " << actualRect.y() << ", expected: " << expected.y(); \
+    EXPECT_TRUE(GeometryTest::ApproximatelyEqual(expected.width(), actualRect.width(), kTestEpsilon)) << "actual: " << actualRect.width() << ", expected: " << expected.width(); \
+    EXPECT_TRUE(GeometryTest::ApproximatelyEqual(expected.height(), actualRect.height(), kTestEpsilon)) << "actual: " << actualRect.height() << ", expected: " << expected.height(); \
+} while (false)
+
+#define CHECK_MAPPINGS(inputRect, expectedVisualRect, expectedTransformedRect, expectedTransformToAncestor, expectedClipInAncestorSpace, localPropertyTreeState, ancestorPropertyTreeState) \
+do { \
+    EXPECT_RECT_EQ(expectedVisualRect, \
+        geometryMapper->LocalToVisualRectInAncestorSpace(inputRect, localPropertyTreeState, ancestorPropertyTreeState)); \
+    EXPECT_RECT_EQ(expectedTransformedRect, \
+        geometryMapper->LocalToAncestorRect(inputRect, localPropertyTreeState, ancestorPropertyTreeState)); \
+    EXPECT_EQ(expectedTransformToAncestor, GetPrecomputedDataForAncestor(ancestorPropertyTreeState).toAncestorTransforms.get(localPropertyTreeState.transform)); \
+    EXPECT_EQ(expectedClipInAncestorSpace, GetPrecomputedDataForAncestor(ancestorPropertyTreeState).toAncestorClipRects.get(localPropertyTreeState.clip)); \
+} while (false)
+
+TEST_F(GeometryMapperTest, Root)
+{
+    FloatRect input(0, 0, 100, 100);
+
+    CHECK_MAPPINGS(input, input, input, rootTransformNode->matrix(), rootClipNode->clipRect().rect(), rootPropertyTreeState(), rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, IdentityTransform)
+{
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(TransformationMatrix(), FloatPoint3D(), rootPropertyTreeState().transform);
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.transform = transform.get();
+
+    FloatRect input(0, 0, 100, 100);
+
+    CHECK_MAPPINGS(input, input, input, transform->matrix(), rootClipNode->clipRect().rect(), localState, rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, TranslationTransform)
+{
+    TransformationMatrix transformMatrix;
+    transformMatrix.translate(20, 10);
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(transformMatrix, FloatPoint3D(), rootPropertyTreeState().transform);
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.transform = transform.get();
+
+    FloatRect input(0, 0, 100, 100);
+    FloatRect output = transformMatrix.mapRect(input);
+
+    CHECK_MAPPINGS(input, output, output, transform->matrix(), rootClipNode->clipRect().rect(), localState, rootPropertyTreeState());
+
+    bool success = false;
+    EXPECT_RECT_EQ(input,
+        geometryMapper->AncestorToLocalRect(output, localState, rootPropertyTreeState(), &success));
+    EXPECT_TRUE(success);
+}
+
+TEST_F(GeometryMapperTest, RotationAndScaleTransform)
+{
+    TransformationMatrix transformMatrix;
+    transformMatrix.rotate(45);
+    transformMatrix.scale(2);
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(transformMatrix, FloatPoint3D(0, 0, 0), rootPropertyTreeState().transform);
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.transform = transform.get();
+
+    FloatRect input(0, 0, 100, 100);
+    FloatRect output = transformMatrix.mapRect(input);
+
+    CHECK_MAPPINGS(input, output, output, transformMatrix, rootClipNode->clipRect().rect(), localState, rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, RotationAndScaleTransformWithTransformOrigin)
+{
+    TransformationMatrix transformMatrix;
+    transformMatrix.rotate(45);
+    transformMatrix.scale(2);
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(transformMatrix, FloatPoint3D(50, 50, 0), rootPropertyTreeState().transform);
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.transform = transform.get();
+
+    FloatRect input(0, 0, 100, 100);
+    transformMatrix.applyTransformOrigin(50, 50, 0);
+    FloatRect output = transformMatrix.mapRect(input);
+
+    CHECK_MAPPINGS(input, output, output, transformMatrix, rootClipNode->clipRect().rect(), localState, rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, NestedTransforms)
+{
+    TransformationMatrix rotateTransform;
+    rotateTransform.rotate(45);
+    RefPtr<TransformPaintPropertyNode> transform1 = TransformPaintPropertyNode::create(rotateTransform, FloatPoint3D(), rootPropertyTreeState().transform);
+
+    TransformationMatrix scaleTransform;
+    scaleTransform.scale(2);
+    RefPtr<TransformPaintPropertyNode> transform2 = TransformPaintPropertyNode::create(scaleTransform, FloatPoint3D(), transform1);
+
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.transform = transform2.get();
+
+    FloatRect input(0, 0, 100, 100);
+    TransformationMatrix final = rotateTransform * scaleTransform;
+    FloatRect output = final.mapRect(input);
+
+    CHECK_MAPPINGS(input, output, output, final, rootClipNode->clipRect().rect(), localState, rootPropertyTreeState());
+
+    // Check the cached matrix for the intermediate transform.
+    EXPECT_EQ(rotateTransform, GetPrecomputedDataForAncestor(rootPropertyTreeState()).toAncestorTransforms.get(transform1.get()));
+}
+
+TEST_F(GeometryMapperTest, NestedTransformsIntermediateDestination)
+{
+    TransformationMatrix rotateTransform;
+    rotateTransform.rotate(45);
+    RefPtr<TransformPaintPropertyNode> transform1 = TransformPaintPropertyNode::create(rotateTransform, FloatPoint3D(), rootPropertyTreeState().transform);
+
+    TransformationMatrix scaleTransform;
+    scaleTransform.scale(2);
+    RefPtr<TransformPaintPropertyNode> transform2 = TransformPaintPropertyNode::create(scaleTransform, FloatPoint3D(), transform1);
+
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.transform = transform2.get();
+
+    PropertyTreeState intermediateState = rootPropertyTreeState();
+    intermediateState.transform = transform1.get();
+
+    FloatRect input(0, 0, 100, 100);
+    FloatRect output = scaleTransform.mapRect(input);
+
+    CHECK_MAPPINGS(input, output, output, scaleTransform, rootClipNode->clipRect().rect(), localState, intermediateState);
+}
+
+TEST_F(GeometryMapperTest, SimpleClip)
+{
+    RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::create(rootTransformNode, FloatRoundedRect(10, 10, 50, 50), rootClipNode);
+
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.clip = clip.get();
+
+    FloatRect input(0, 0, 100, 100);
+    FloatRect output(10, 10, 50, 50);
+
+    CHECK_MAPPINGS(
+        input, // Input
+        output, // Visual rect
+        input, // Transformed rect (not clipped).
+        rootTransformNode->matrix(), // Transform matrix to ancestor space
+        clip->clipRect().rect(), // Clip rect in ancestor space
+        localState, rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, ClipBeforeTransform)
+{
+    TransformationMatrix rotateTransform;
+    rotateTransform.rotate(45);
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(rotateTransform, FloatPoint3D(), rootPropertyTreeState().transform);
+
+    RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::create(transform.get(), FloatRoundedRect(10, 10, 50, 50), rootClipNode);
+
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.clip = clip.get();
+    localState.transform = transform.get();
+
+    FloatRect input(0, 0, 100, 100);
+    FloatRect output(input);
+    output.intersect(clip->clipRect().rect());
+    output = rotateTransform.mapRect(output);
+
+    CHECK_MAPPINGS(
+        input, // Input
+        output, // Visual rect
+        rotateTransform.mapRect(input), // Transformed rect (not clipped).
+        rotateTransform, // Transform matrix to ancestor space
+        rotateTransform.mapRect(clip->clipRect().rect()), // Clip rect in ancestor space
+        localState, rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, ClipAfterTransform)
+{
+    TransformationMatrix rotateTransform;
+    rotateTransform.rotate(45);
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(rotateTransform, FloatPoint3D(), rootPropertyTreeState().transform);
+
+    RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::create(rootTransformNode.get(), FloatRoundedRect(10, 10, 200, 200), rootClipNode);
+
+    PropertyTreeState localState = rootPropertyTreeState();
+    localState.clip = clip.get();
+    localState.transform = transform.get();
+
+    FloatRect input(0, 0, 100, 100);
+    FloatRect output(input);
+    output = rotateTransform.mapRect(output);
+    output.intersect(clip->clipRect().rect());
+
+    CHECK_MAPPINGS(
+        input, // Input
+        output, // Visual rect
+        rotateTransform.mapRect(input), // Transformed rect (not clipped)
+        rotateTransform, // Transform matrix to ancestor space
+        clip->clipRect().rect(), // Clip rect in ancestor space
+        localState, rootPropertyTreeState());
+}
+
+TEST_F(GeometryMapperTest, TwoClipsWithTransformBetween)
+{
+    RefPtr<ClipPaintPropertyNode> clip1 = ClipPaintPropertyNode::create(rootTransformNode.get(), FloatRoundedRect(10, 10, 200, 200), rootClipNode);
+
+    TransformationMatrix rotateTransform;
+    rotateTransform.rotate(45);
+    RefPtr<TransformPaintPropertyNode> transform = TransformPaintPropertyNode::create(rotateTransform, FloatPoint3D(), rootPropertyTreeState().transform);
+
+    RefPtr<ClipPaintPropertyNode> clip2 = ClipPaintPropertyNode::create(transform.get(), FloatRoundedRect(10, 10, 200, 200), clip1.get());
+
+    FloatRect input(0, 0, 100, 100);
+
+    {
+        PropertyTreeState localState = rootPropertyTreeState();
+        localState.clip = clip1.get();
+        localState.transform = transform.get();
+
+        FloatRect output(input);
+        output = rotateTransform.mapRect(output);
+        output.intersect(clip1->clipRect().rect());
+
+        CHECK_MAPPINGS(
+            input, // Input
+            output, // Visual rect
+            rotateTransform.mapRect(input), // Transformed rect (not clipped)
+            rotateTransform, // Transform matrix to ancestor space
+            clip1->clipRect().rect(), // Clip rect in ancestor space
+            localState, rootPropertyTreeState());
+    }
+
+    {
+        PropertyTreeState localState = rootPropertyTreeState();
+        localState.clip = clip2.get();
+        localState.transform = transform.get();
+
+
+        FloatRect mappedClip = rotateTransform.mapRect(clip2->clipRect().rect());
+        mappedClip.intersect(clip1->clipRect().rect());
+
+        // All clips are performed in the space of the ancestor. In cases such as this, this means the
+        // clip is a bit lossy.
+        FloatRect output(input);
+        // Map to transformed rect in ancestor space.
+        output = rotateTransform.mapRect(output);
+        // Intersect with all clips between local and ancestor, independently mapped to ancestor space.
+        output.intersect(mappedClip);
+
+        CHECK_MAPPINGS(
+            input, // Input
+            output, // Visual rect
+            rotateTransform.mapRect(input), // Transformed rect (not clipped)
+            rotateTransform, // Transform matrix to ancestor space
+            mappedClip, // Clip rect in ancestor space
+            localState, rootPropertyTreeState());
+    }
+}
+
+} // namespace blink