cc: Do a safe intersect when gathering images.

cc/playback/discardable_image_map_unittest.cc

 // Copyright 2015 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/playback/discardable_image_map.h"
 
 #include <stddef.h>
 
 #include <memory>
 
@@ skipping 290 matching lines @@
   DiscardableImageMap image_map;
   {
     DiscardableImageMap::ScopedMetadataGenerator generator(&image_map,
                                                            visible_rect.size());
     display_list->Raster(generator.canvas(), nullptr, visible_rect, 1.f);
   }
   std::vector<PositionDrawImage> images =
       GetDiscardableImagesInRect(image_map, gfx::Rect(0, 0, 1, 1));
   EXPECT_EQ(1u, images.size());
   EXPECT_TRUE(images[0].image == discardable_image);
-  EXPECT_EQ(gfx::Rect(0, 0, 1 << 25, 1 << 25), images[0].image_rect);
+  EXPECT_EQ(gfx::Rect(0, 0, 2048, 2048), images[0].image_rect);
 }
 
 TEST_F(DiscardableImageMapTest, PaintDestroyedWhileImageIsDrawn) {
   gfx::Rect visible_rect(2048, 2048);
   FakeContentLayerClient content_layer_client;
   content_layer_client.set_bounds(visible_rect.size());
 
   sk_sp<SkImage> discardable_image = CreateDiscardableImage(gfx::Size(10, 10));
 
   DiscardableImageMap image_map;
   {
     DiscardableImageMap::ScopedMetadataGenerator generator(&image_map,
                                                            visible_rect.size());
     {
       std::unique_ptr<SkPaint> paint(new SkPaint());
       generator.canvas()->saveLayer(gfx::RectToSkRect(visible_rect),
                                     paint.get());
     }
     generator.canvas()->drawImage(discardable_image, 0, 0, nullptr);
     generator.canvas()->restore();
   }
 
   std::vector<PositionDrawImage> images =
       GetDiscardableImagesInRect(image_map, gfx::Rect(0, 0, 1, 1));
   EXPECT_EQ(1u, images.size());
   EXPECT_TRUE(images[0].image == discardable_image);
 }
 
+TEST_F(DiscardableImageMapTest, GetDiscardableImagesInRectMaxImage) {
+  gfx::Rect visible_rect(2048, 2048);
+  FakeContentLayerClient content_layer_client;
+  content_layer_client.set_bounds(visible_rect.size());
+
+  int dimension = std::numeric_limits<int>::max();
+  sk_sp<SkImage> discardable_image =
+      CreateDiscardableImage(gfx::Size(dimension, dimension));
+  SkPaint paint;
+  content_layer_client.add_draw_image(discardable_image, gfx::Point(42, 42),
+                                      paint);
+
+  scoped_refptr<DisplayItemList> display_list =
+      content_layer_client.PaintContentsToDisplayList(
+          ContentLayerClient::PAINTING_BEHAVIOR_NORMAL);
+
+  DiscardableImageMap image_map;
+  {
+    DiscardableImageMap::ScopedMetadataGenerator generator(&image_map,
+                                                           visible_rect.size());
+    display_list->Raster(generator.canvas(), nullptr, visible_rect, 1.f);
+  }
+  std::vector<PositionDrawImage> images =
+      GetDiscardableImagesInRect(image_map, gfx::Rect(42, 42, 1, 1));
+  EXPECT_EQ(1u, images.size());
+  EXPECT_TRUE(images[0].image == discardable_image);
+  EXPECT_EQ(gfx::Rect(42, 42, 2006, 2006), images[0].image_rect);
+}
+
+TEST_F(DiscardableImageMapTest, GetDiscardableImagesInRectMaxImageMaxLayer) {
+  int dimension = static_cast<int>(
+      static_cast<float>(std::numeric_limits<int>::max() - 64));

[enne (OOO), 2016/08/10 00:07:12]

This really needs a comment.

[vmpstr, 2016/08/10 19:19:39]

Done.

+  gfx::Rect visible_rect(dimension, dimension);
+  FakeContentLayerClient content_layer_client;
+  content_layer_client.set_bounds(visible_rect.size());
+
+  sk_sp<SkImage> discardable_image =
+      CreateDiscardableImage(gfx::Size(dimension, dimension));
+  SkPaint paint;
+  content_layer_client.add_draw_image(discardable_image, gfx::Point(0, 0),
+                                      paint);
+  content_layer_client.add_draw_image(discardable_image, gfx::Point(10000, 0),
+                                      paint);
+  content_layer_client.add_draw_image(discardable_image,
+                                      gfx::Point(-10000, 500), paint);
+
+  scoped_refptr<DisplayItemList> display_list =
+      content_layer_client.PaintContentsToDisplayList(
+          ContentLayerClient::PAINTING_BEHAVIOR_NORMAL);
+
+  DiscardableImageMap image_map;
+  {
+    DiscardableImageMap::ScopedMetadataGenerator generator(&image_map,
+                                                           visible_rect.size());
+    display_list->Raster(generator.canvas(), nullptr, visible_rect, 1.f);
+  }
+  std::vector<PositionDrawImage> images =
+      GetDiscardableImagesInRect(image_map, gfx::Rect(0, 0, 1, 1));
+  EXPECT_EQ(1u, images.size());
+  EXPECT_EQ(gfx::Rect(0, 0, dimension, dimension), images[0].image_rect);
+
+  images = GetDiscardableImagesInRect(image_map, gfx::Rect(10000, 0, 1, 1));
+  EXPECT_EQ(2u, images.size());
+  int expected10k = static_cast<int>(static_cast<float>(dimension - 10000));
+  int expected500 = static_cast<int>(static_cast<float>(dimension - 500));
+  EXPECT_EQ(gfx::Rect(10000, 0, expected10k, dimension), images[1].image_rect);
+  EXPECT_EQ(gfx::Rect(0, 0, dimension, dimension), images[0].image_rect);
+
+  images = GetDiscardableImagesInRect(image_map, gfx::Rect(0, 500, 1, 1));
+  EXPECT_EQ(2u, images.size());
+  EXPECT_EQ(gfx::Rect(0, 500, expected10k, expected500), images[1].image_rect);
+  EXPECT_EQ(gfx::Rect(0, 0, dimension, dimension), images[0].image_rect);
+}
+
+TEST_F(DiscardableImageMapTest, GetDiscardableImagesRectInBounds) {
+  gfx::Rect visible_rect(1000, 1000);
+  FakeContentLayerClient content_layer_client;
+  content_layer_client.set_bounds(visible_rect.size());
+
+  sk_sp<SkImage> discardable_image =
+      CreateDiscardableImage(gfx::Size(100, 100));
+  sk_sp<SkImage> long_discardable_image =
+      CreateDiscardableImage(gfx::Size(10000, 100));
+
+  SkPaint paint;
+  content_layer_client.add_draw_image(discardable_image, gfx::Point(-10, -11),
+                                      paint);
+  content_layer_client.add_draw_image(discardable_image, gfx::Point(950, 951),
+                                      paint);
+  content_layer_client.add_draw_image(long_discardable_image,
+                                      gfx::Point(-100, 500), paint);
+
+  scoped_refptr<DisplayItemList> display_list =
+      content_layer_client.PaintContentsToDisplayList(
+          ContentLayerClient::PAINTING_BEHAVIOR_NORMAL);
+
+  DiscardableImageMap image_map;
+  {
+    DiscardableImageMap::ScopedMetadataGenerator generator(&image_map,
+                                                           visible_rect.size());
+    display_list->Raster(generator.canvas(), nullptr, visible_rect, 1.f);
+  }
+  std::vector<PositionDrawImage> images =
+      GetDiscardableImagesInRect(image_map, gfx::Rect(0, 0, 1, 1));
+  EXPECT_EQ(1u, images.size());
+  EXPECT_EQ(gfx::Rect(0, 0, 90, 89), images[0].image_rect);
+
+  images = GetDiscardableImagesInRect(image_map, gfx::Rect(999, 999, 1, 1));
+  EXPECT_EQ(1u, images.size());
+  EXPECT_EQ(gfx::Rect(950, 951, 50, 49), images[0].image_rect);
+
+  images = GetDiscardableImagesInRect(image_map, gfx::Rect(0, 500, 1, 1));
+  EXPECT_EQ(1u, images.size());
+  EXPECT_EQ(gfx::Rect(0, 500, 1000, 100), images[0].image_rect);
+}
+
 }  // namespace cc