Prioritize tiles near the viewport in out-of-viewport layers

cc/resources/picture_layer_tiling_unittest.cc

 // Copyright 2012 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 "cc/resources/picture_layer_tiling.h"
 
 #include "cc/test/fake_picture_layer_tiling_client.h"
+#include "cc/test/geometry_test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/size_conversions.h"
 
 namespace cc {
 namespace {
 
 class PictureLayerTilingIteratorTest : public testing::Test {
  public:
   PictureLayerTilingIteratorTest() {}
@@ skipping 155 matching lines @@
   VerifyTilesCoverNonContainedRect(1.5f, gfx::Rect(-1000, 100, 2000, 100));
   VerifyTilesCoverNonContainedRect(0.5f, gfx::Rect(-1000, 100, 2000, 100));
 }
 
 TEST(PictureLayerTilingTest, ExpandRectEqual) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(-1000, -1000, 10000, 10000);
   int64 target_area = 100 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(in.ToString(), out.ToString());
+  EXPECT_RECT_EQ(in, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectSmaller) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(-1000, -1000, 10000, 10000);
   int64 target_area = 100 * 100;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
   EXPECT_EQ(out.bottom() - in.bottom(), in.y() - out.y());
   EXPECT_EQ(out.right() - in.right(), in.x() - out.x());
@@ skipping 14 matching lines @@
   EXPECT_NEAR(200 * 200, out.width() * out.height(), 100);
   EXPECT_TRUE(bounds.Contains(out));
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedSmaller) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(50, 60, 40, 30);
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(bounds.ToString(), out.ToString());
+  EXPECT_RECT_EQ(bounds, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedEqual) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds = in;
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(bounds.ToString(), out.ToString());
+  EXPECT_RECT_EQ(bounds, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedSmallerStretchVertical) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(45, 0, 90, 300);
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(bounds.ToString(), out.ToString());
+  EXPECT_RECT_EQ(bounds, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedEqualStretchVertical) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(40, 0, 100, 300);
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(bounds.ToString(), out.ToString());
+  EXPECT_RECT_EQ(bounds, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedSmallerStretchHorizontal) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(0, 55, 180, 190);
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(bounds.ToString(), out.ToString());
+  EXPECT_RECT_EQ(bounds, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedEqualStretchHorizontal) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(0, 50, 180, 200);
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
-  EXPECT_EQ(bounds.ToString(), out.ToString());
+  EXPECT_RECT_EQ(bounds, out);
 }
 
 TEST(PictureLayerTilingTest, ExpandRectBoundedLeft) {
   gfx::Rect in(40, 50, 100, 200);
   gfx::Rect bounds(20, -1000, 10000, 10000);
   int64 target_area = 200 * 200;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
   EXPECT_EQ(out.bottom() - in.bottom(), in.y() - out.y());
   EXPECT_EQ(out.bottom() - in.bottom(), out.right() - in.right());
@@ skipping 68 matching lines @@
       in, target_area, bounds);
   EXPECT_EQ(30, out.bottom() - in.bottom());
   EXPECT_EQ(50, in.y() - out.y());
   EXPECT_EQ(out.right() - in.right(), in.x() - out.x());
   EXPECT_LE(out.width() * out.height(), target_area);
   EXPECT_GT(out.width() * out.height(),
             target_area - out.height() * 2);
   EXPECT_TRUE(bounds.Contains(out));
 }
 
-TEST(PictureLayerTilingTest, ExpandRectOutOfBounds) {
-  gfx::Rect in(40, 50, 100, 200);
+TEST(PictureLayerTilingTest, ExpandRectOutOfBoundsFarAway) {
+  gfx::Rect in(400, 500, 100, 200);
   gfx::Rect bounds(0, 0, 10, 10);
   int64 target_area = 400 * 400;
   gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
       in, target_area, bounds);
   EXPECT_TRUE(out.IsEmpty());
 }
 
+TEST(PictureLayerTilingTest, ExpandRectOutOfBoundsExpandedFullyCover) {
+  gfx::Rect in(40, 50, 100, 100);
+  gfx::Rect bounds(0, 0, 10, 10);
+  int64 target_area = 400 * 400;
+  gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
+      in, target_area, bounds);
+  EXPECT_RECT_EQ(bounds, out);
+}
+
+TEST(PictureLayerTilingTest, ExpandRectOutOfBoundsExpandedPartlyCover) {
+  gfx::Rect in(600, 600, 100, 100);
+  gfx::Rect bounds(0, 0, 500, 500);
+  int64 target_area = 400 * 400;
+  gfx::Rect out = PictureLayerTiling::ExpandRectEquallyToAreaBoundedBy(
+      in, target_area, bounds);
+  EXPECT_EQ(bounds.right(), out.right());
+  EXPECT_EQ(bounds.bottom(), out.bottom());
+  EXPECT_LE(out.width() * out.height(), target_area);

[danakj, 2013/04/10 16:46:24]

can you give a lower bound on the out rect's area as well so we know it's
covering the target_area?

In this case, with two edges snapped to the bounding rect, I think this should
pass?
EXPECT_GT(out.width() * out.height(),
          target_area - out.width() - out.height());

[Xianzhu, 2013/04/10 17:08:37]

Done.

+  EXPECT_TRUE(bounds.Contains(out));
+}
+
 }  // namespace
 }  // namespace cc