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

cc/resources/picture_layer_tiling_unittest.cc

Index: cc/resources/picture_layer_tiling_unittest.cc
diff --git a/cc/resources/picture_layer_tiling_unittest.cc b/cc/resources/picture_layer_tiling_unittest.cc
index 91043e67b48006e13d72f42781c97fd55828fcdb..9e5091499fb055e8880d16fec694c09beb89cac2 100644
--- a/cc/resources/picture_layer_tiling_unittest.cc
+++ b/cc/resources/picture_layer_tiling_unittest.cc
@@ -5,6 +5,7 @@
 #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"
@@ -180,7 +181,7 @@ TEST(PictureLayerTilingTest, ExpandRectEqual) {
   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) {
@@ -215,7 +216,7 @@ TEST(PictureLayerTilingTest, ExpandRectBoundedSmaller) {
   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) {
@@ -224,7 +225,7 @@ TEST(PictureLayerTilingTest, ExpandRectBoundedEqual) {
   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) {
@@ -233,7 +234,7 @@ TEST(PictureLayerTilingTest, ExpandRectBoundedSmallerStretchVertical) {
   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) {
@@ -242,7 +243,7 @@ TEST(PictureLayerTilingTest, ExpandRectBoundedEqualStretchVertical) {
   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) {
@@ -251,7 +252,7 @@ TEST(PictureLayerTilingTest, ExpandRectBoundedSmallerStretchHorizontal) {
   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) {
@@ -260,7 +261,7 @@ TEST(PictureLayerTilingTest, ExpandRectBoundedEqualStretchHorizontal) {
   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) {
@@ -349,8 +350,8 @@ TEST(PictureLayerTilingTest, ExpandRectSquishedVertically) {
   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(
@@ -358,5 +359,26 @@ TEST(PictureLayerTilingTest, ExpandRectOutOfBounds) {
   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