cc/playback/picture_pile_impl_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 "base/memory/scoped_ptr.h"
#include "cc/test/fake_picture_pile_impl.h"
#include "cc/test/skia_common.h"
#include "skia/ext/refptr.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/skia/include/core/SkPixelRef.h"
#include "third_party/skia/include/core/SkShader.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/size_conversions.h"

namespace cc {
namespace {

TEST(PicturePileImplTest, AnalyzeIsSolidUnscaled) {
  gfx::Size tile_size(100, 100);
  gfx::Size layer_bounds(400, 400);

  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);

  SkPaint solid_paint;
  SkColor solid_color = SkColorSetARGB(255, 12, 23, 34);
  solid_paint.setColor(solid_color);

  SkColor non_solid_color = SkColorSetARGB(128, 45, 56, 67);
  SkPaint non_solid_paint;
  non_solid_paint.setColor(non_solid_color);

  recording_source->add_draw_rect_with_paint(gfx::Rect(0, 0, 400, 400),
                                             solid_paint);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  // Ensure everything is solid.
  for (int y = 0; y <= 300; y += 100) {
    for (int x = 0; x <= 300; x += 100) {
      RasterSource::SolidColorAnalysis analysis;
      gfx::Rect rect(x, y, 100, 100);
      pile->PerformSolidColorAnalysis(rect, 1.0, &analysis);
      EXPECT_TRUE(analysis.is_solid_color) << rect.ToString();
      EXPECT_EQ(analysis.solid_color, solid_color) << rect.ToString();
    }
  }

  // Add one non-solid pixel and recreate the raster source.
  recording_source->add_draw_rect_with_paint(gfx::Rect(50, 50, 1, 1),
                                             non_solid_paint);
  recording_source->Rerecord();
  pile = FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  RasterSource::SolidColorAnalysis analysis;
  pile->PerformSolidColorAnalysis(gfx::Rect(0, 0, 100, 100), 1.0, &analysis);
  EXPECT_FALSE(analysis.is_solid_color);

  pile->PerformSolidColorAnalysis(gfx::Rect(100, 0, 100, 100), 1.0, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);

  // Boundaries should be clipped.
  analysis.is_solid_color = false;
  pile->PerformSolidColorAnalysis(gfx::Rect(350, 0, 100, 100), 1.0, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);

  analysis.is_solid_color = false;
  pile->PerformSolidColorAnalysis(gfx::Rect(0, 350, 100, 100), 1.0, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);

  analysis.is_solid_color = false;
  pile->PerformSolidColorAnalysis(gfx::Rect(350, 350, 100, 100), 1.0,
                                  &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);
}

TEST(PicturePileImplTest, AnalyzeIsSolidScaled) {
  gfx::Size tile_size(100, 100);
  gfx::Size layer_bounds(400, 400);

  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);

  SkColor solid_color = SkColorSetARGB(255, 12, 23, 34);
  SkPaint solid_paint;
  solid_paint.setColor(solid_color);

  SkColor non_solid_color = SkColorSetARGB(128, 45, 56, 67);
  SkPaint non_solid_paint;
  non_solid_paint.setColor(non_solid_color);

  recording_source->add_draw_rect_with_paint(gfx::Rect(0, 0, 400, 400),
                                             solid_paint);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  // Ensure everything is solid.
  for (int y = 0; y <= 30; y += 10) {
    for (int x = 0; x <= 30; x += 10) {
      RasterSource::SolidColorAnalysis analysis;
      gfx::Rect rect(x, y, 10, 10);
      pile->PerformSolidColorAnalysis(rect, 0.1f, &analysis);
      EXPECT_TRUE(analysis.is_solid_color) << rect.ToString();
      EXPECT_EQ(analysis.solid_color, solid_color) << rect.ToString();
    }
  }

  // Add one non-solid pixel and recreate the raster source.
  recording_source->add_draw_rect_with_paint(gfx::Rect(50, 50, 1, 1),
                                             non_solid_paint);
  recording_source->Rerecord();
  pile = FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  RasterSource::SolidColorAnalysis analysis;
  pile->PerformSolidColorAnalysis(gfx::Rect(0, 0, 10, 10), 0.1f, &analysis);
  EXPECT_FALSE(analysis.is_solid_color);

  pile->PerformSolidColorAnalysis(gfx::Rect(10, 0, 10, 10), 0.1f, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);

  // Boundaries should be clipped.
  analysis.is_solid_color = false;
  pile->PerformSolidColorAnalysis(gfx::Rect(35, 0, 10, 10), 0.1f, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);

  analysis.is_solid_color = false;
  pile->PerformSolidColorAnalysis(gfx::Rect(0, 35, 10, 10), 0.1f, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);

  analysis.is_solid_color = false;
  pile->PerformSolidColorAnalysis(gfx::Rect(35, 35, 10, 10), 0.1f, &analysis);
  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, solid_color);
}

TEST(PicturePileImplTest, AnalyzeIsSolidEmpty) {
  gfx::Size tile_size(100, 100);
  gfx::Size layer_bounds(400, 400);

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFilledPile(tile_size, layer_bounds);
  RasterSource::SolidColorAnalysis analysis;
  EXPECT_FALSE(analysis.is_solid_color);

  pile->PerformSolidColorAnalysis(gfx::Rect(0, 0, 400, 400), 1.f, &analysis);

  EXPECT_TRUE(analysis.is_solid_color);
  EXPECT_EQ(analysis.solid_color, SkColorSetARGB(0, 0, 0, 0));
}

TEST(PicturePileImplTest, PixelRefIteratorDiscardableRefsOneTile) {
  gfx::Size tile_size(256, 256);
  gfx::Size layer_bounds(512, 512);

  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);

  SkBitmap discardable_bitmap[2][2];
  CreateBitmap(gfx::Size(32, 32), "discardable", &discardable_bitmap[0][0]);
  CreateBitmap(gfx::Size(32, 32), "discardable", &discardable_bitmap[0][1]);
  CreateBitmap(gfx::Size(32, 32), "discardable", &discardable_bitmap[1][1]);

  // Discardable pixel refs are found in the following cells:
  // |---|---|
  // | x | x |
  // |---|---|
  // |   | x |
  // |---|---|
  recording_source->add_draw_bitmap(discardable_bitmap[0][0], gfx::Point(0, 0));
  recording_source->add_draw_bitmap(discardable_bitmap[0][1],
                                    gfx::Point(260, 0));
  recording_source->add_draw_bitmap(discardable_bitmap[1][1],
                                    gfx::Point(260, 260));
  recording_source->SetGatherPixelRefs(true);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  // Tile sized iterators. These should find only one pixel ref.
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 0, 256, 256), 1.0, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 0, 512, 512), 2.0, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 0, 128, 128), 0.5, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  // Shifted tile sized iterators. These should find only one pixel ref.
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(260, 260, 256, 256), 1.0, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(520, 520, 512, 512), 2.0, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(130, 130, 128, 128), 0.5, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  // Ensure there's no discardable pixel refs in the empty cell
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 256, 256, 256), 1.0, pile.get());
    EXPECT_FALSE(iterator);
  }
  // Layer sized iterators. These should find three pixel ref.
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 0, 512, 512), 1.0, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][1].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 0, 1024, 1024), 2.0, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][1].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    PicturePileImpl::PixelRefIterator iterator(
        gfx::Rect(0, 0, 256, 256), 0.5, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0][1].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
    EXPECT_FALSE(++iterator);
  }

  // Copy test.
  PicturePileImpl::PixelRefIterator iterator(
      gfx::Rect(0, 0, 512, 512), 1.0, pile.get());
  EXPECT_TRUE(iterator);
  EXPECT_TRUE(*iterator == discardable_bitmap[0][0].pixelRef());
  EXPECT_TRUE(++iterator);
  EXPECT_TRUE(*iterator == discardable_bitmap[0][1].pixelRef());

  // copy now points to the same spot as iterator,
  // but both can be incremented independently.
  PicturePileImpl::PixelRefIterator copy = iterator;
  EXPECT_TRUE(++iterator);
  EXPECT_TRUE(*iterator == discardable_bitmap[1][1].pixelRef());
  EXPECT_FALSE(++iterator);

  EXPECT_TRUE(copy);
  EXPECT_TRUE(*copy == discardable_bitmap[0][1].pixelRef());
  EXPECT_TRUE(++copy);
  EXPECT_TRUE(*copy == discardable_bitmap[1][1].pixelRef());
  EXPECT_FALSE(++copy);
}

TEST(PicturePileImplTest, RasterFullContents) {
  gfx::Size tile_size(1000, 1000);
  gfx::Size layer_bounds(3, 5);
  float contents_scale = 1.5f;
  float raster_divisions = 2.f;

  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);
  recording_source->SetBackgroundColor(SK_ColorBLACK);
  recording_source->SetIsSolidColor(false);
  recording_source->SetRequiresClear(false);
  recording_source->SetClearCanvasWithDebugColor(false);

  // Because the caller sets content opaque, it also promises that it
  // has at least filled in layer_bounds opaquely.
  SkPaint white_paint;
  white_paint.setColor(SK_ColorWHITE);
  recording_source->add_draw_rect_with_paint(gfx::Rect(layer_bounds),
                                             white_paint);

  recording_source->SetMinContentsScale(contents_scale);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  gfx::Size content_bounds(
      gfx::ToCeiledSize(gfx::ScaleSize(layer_bounds, contents_scale)));

  // Simulate drawing into different tiles at different offsets.
  int step_x = std::ceil(content_bounds.width() / raster_divisions);
  int step_y = std::ceil(content_bounds.height() / raster_divisions);
  for (int offset_x = 0; offset_x < content_bounds.width();
       offset_x += step_x) {
    for (int offset_y = 0; offset_y < content_bounds.height();
         offset_y += step_y) {
      gfx::Rect content_rect(offset_x, offset_y, step_x, step_y);
      content_rect.Intersect(gfx::Rect(content_bounds));

      // Simulate a canvas rect larger than the content rect.  Every pixel
      // up to one pixel outside the content rect is guaranteed to be opaque.
      // Outside of that is undefined.
      gfx::Rect canvas_rect(content_rect);
      canvas_rect.Inset(0, 0, -1, -1);

      SkBitmap bitmap;
      bitmap.allocN32Pixels(canvas_rect.width(), canvas_rect.height());
      SkCanvas canvas(bitmap);
      canvas.clear(SK_ColorTRANSPARENT);

      pile->PlaybackToCanvas(&canvas, canvas_rect, canvas_rect, contents_scale);

      SkColor* pixels = reinterpret_cast<SkColor*>(bitmap.getPixels());
      int num_pixels = bitmap.width() * bitmap.height();
      bool all_white = true;
      for (int i = 0; i < num_pixels; ++i) {
        EXPECT_EQ(SkColorGetA(pixels[i]), 255u);
        all_white &= (SkColorGetR(pixels[i]) == 255);
        all_white &= (SkColorGetG(pixels[i]) == 255);
        all_white &= (SkColorGetB(pixels[i]) == 255);
      }

      // If the canvas doesn't extend past the edge of the content,
      // it should be entirely white. Otherwise, the edge of the content
      // will be non-white.
      EXPECT_EQ(all_white, gfx::Rect(content_bounds).Contains(canvas_rect));
    }
  }
}

TEST(PicturePileImpl, RasterContentsTransparent) {
  gfx::Size tile_size(1000, 1000);
  gfx::Size layer_bounds(5, 3);
  float contents_scale = 0.5f;

  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);
  recording_source->SetBackgroundColor(SK_ColorTRANSPARENT);
  recording_source->SetRequiresClear(true);
  recording_source->SetMinContentsScale(contents_scale);
  recording_source->SetClearCanvasWithDebugColor(false);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);
  gfx::Size content_bounds(
      gfx::ToCeiledSize(gfx::ScaleSize(layer_bounds, contents_scale)));

  gfx::Rect canvas_rect(content_bounds);
  canvas_rect.Inset(0, 0, -1, -1);

  SkBitmap bitmap;
  bitmap.allocN32Pixels(canvas_rect.width(), canvas_rect.height());
  SkCanvas canvas(bitmap);

  pile->PlaybackToCanvas(&canvas, canvas_rect, canvas_rect, contents_scale);

  SkColor* pixels = reinterpret_cast<SkColor*>(bitmap.getPixels());
  int num_pixels = bitmap.width() * bitmap.height();
  for (int i = 0; i < num_pixels; ++i) {
    EXPECT_EQ(SkColorGetA(pixels[i]), 0u);
  }
}

class OverlapTest : public ::testing::TestWithParam<float> {
 public:
  static float MinContentsScale() { return 1.f / 4.f; }
};

TEST_P(OverlapTest, NoOverlap) {
  gfx::Size tile_size(10, 10);
  gfx::Size layer_bounds(30, 30);
  gfx::Size bigger_than_layer_bounds(300, 300);
  float contents_scale = GetParam();
  // Pick an opaque color to not have to deal with premultiplication off-by-one.
  SkColor test_color = SkColorSetARGB(255, 45, 56, 67);

  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);
  recording_source->SetBackgroundColor(SK_ColorTRANSPARENT);
  recording_source->SetRequiresClear(true);
  recording_source->SetMinContentsScale(MinContentsScale());
  recording_source->SetClearCanvasWithDebugColor(true);

  SkPaint color_paint;
  color_paint.setColor(test_color);
  // Additive paint, so that if two paints overlap, the color will change.
  color_paint.setXfermodeMode(SkXfermode::kPlus_Mode);
  // Paint outside the layer to make sure that blending works.
  recording_source->add_draw_rect_with_paint(
      gfx::RectF(bigger_than_layer_bounds), color_paint);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);
  gfx::Size content_bounds(
      gfx::ToCeiledSize(gfx::ScaleSize(layer_bounds, contents_scale)));

  SkBitmap bitmap;
  bitmap.allocN32Pixels(content_bounds.width(), content_bounds.height());
  SkCanvas canvas(bitmap);

  pile->PlaybackToCanvas(&canvas, gfx::Rect(content_bounds),
                         gfx::Rect(content_bounds), contents_scale);

  for (int y = 0; y < bitmap.height(); y++) {
    for (int x = 0; x < bitmap.width(); x++) {
      SkColor color = bitmap.getColor(x, y);
      EXPECT_EQ(SkColorGetR(test_color), SkColorGetR(color)) << "x: " << x
                                                             << ", y: " << y;
      EXPECT_EQ(SkColorGetG(test_color), SkColorGetG(color)) << "x: " << x
                                                             << ", y: " << y;
      EXPECT_EQ(SkColorGetB(test_color), SkColorGetB(color)) << "x: " << x
                                                             << ", y: " << y;
      EXPECT_EQ(SkColorGetA(test_color), SkColorGetA(color)) << "x: " << x
                                                             << ", y: " << y;
      if (test_color != color)
        break;
    }
  }
}

INSTANTIATE_TEST_CASE_P(PicturePileImpl,
                        OverlapTest,
                        ::testing::Values(1.f, 0.873f, 1.f / 4.f, 4.f));

TEST(PicturePileImplTest, PixelRefIteratorBorders) {
  // 3 tile width / 1 tile height pile
  gfx::Size tile_size(128, 128);
  gfx::Size layer_bounds(320, 128);

  // Fake picture pile uses a tile grid the size of the tile.  So,
  // any iteration that intersects with a tile will return all pixel refs
  // inside of it.
  scoped_ptr<FakePicturePile> recording_source =
      FakePicturePile::CreateFilledPile(tile_size, layer_bounds);
  recording_source->SetMinContentsScale(0.5f);

  // Bitmaps 0-2 are exactly on tiles 0-2, so that they overlap the borders
  // of adjacent tiles.
  gfx::Rect bitmap_rects[] = {
      recording_source->tiling().TileBounds(0, 0),
      recording_source->tiling().TileBounds(1, 0),
      recording_source->tiling().TileBounds(2, 0),
  };
  SkBitmap discardable_bitmap[arraysize(bitmap_rects)];

  for (size_t i = 0; i < arraysize(bitmap_rects); ++i) {
    CreateBitmap(bitmap_rects[i].size(), "discardable", &discardable_bitmap[i]);
    recording_source->add_draw_bitmap(discardable_bitmap[i],
                                      bitmap_rects[i].origin());
  }

  recording_source->SetGatherPixelRefs(true);
  recording_source->Rerecord();

  scoped_refptr<FakePicturePileImpl> pile =
      FakePicturePileImpl::CreateFromPile(recording_source.get(), nullptr);

  // Sanity check that bitmaps 0-2 intersect the borders of their adjacent
  // tiles, but not the actual tiles.
  EXPECT_TRUE(
      bitmap_rects[0].Intersects(pile->tiling().TileBoundsWithBorder(1, 0)));
  EXPECT_FALSE(bitmap_rects[0].Intersects(pile->tiling().TileBounds(1, 0)));
  EXPECT_TRUE(
      bitmap_rects[1].Intersects(pile->tiling().TileBoundsWithBorder(0, 0)));
  EXPECT_FALSE(bitmap_rects[1].Intersects(pile->tiling().TileBounds(0, 0)));
  EXPECT_TRUE(
      bitmap_rects[1].Intersects(pile->tiling().TileBoundsWithBorder(2, 0)));
  EXPECT_FALSE(bitmap_rects[1].Intersects(pile->tiling().TileBounds(2, 0)));
  EXPECT_TRUE(
      bitmap_rects[2].Intersects(pile->tiling().TileBoundsWithBorder(1, 0)));
  EXPECT_FALSE(bitmap_rects[2].Intersects(pile->tiling().TileBounds(1, 0)));

  // Tile-sized iterators.
  {
    // Because tile 0's borders extend onto tile 1, it will include both
    // bitmap 0 and 1.  However, it should *not* include bitmap 2.
    PicturePileImpl::PixelRefIterator iterator(
        pile->tiling().TileBounds(0, 0), 1.f, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    // Tile 1 + borders hits all bitmaps.
    PicturePileImpl::PixelRefIterator iterator(
        pile->tiling().TileBounds(1, 0), 1.f, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[0].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[2].pixelRef());
    EXPECT_FALSE(++iterator);
  }
  {
    // Tile 2 should not include bitmap 0, which is only on tile 0 and the
    // borders of tile 1.
    PicturePileImpl::PixelRefIterator iterator(
        pile->tiling().TileBounds(2, 0), 1.f, pile.get());
    EXPECT_TRUE(iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[1].pixelRef());
    EXPECT_TRUE(++iterator);
    EXPECT_TRUE(*iterator == discardable_bitmap[2].pixelRef());
    EXPECT_FALSE(++iterator);
  }
}

}  // namespace
}  // namespace cc