Reland Allow one-copy and zero-copy task tile worker pools to use compressed textures.

BUG=434699
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1713503002

Cr-Commit-Position: refs/heads/master@{#376711}

27 files changed, 252 insertions, 113 deletions

diff --git a/blimp/client/feature/compositor/blimp_layer_tree_settings.cc b/blimp/client/feature/compositor/blimp_layer_tree_settings.cc
index c78604c..2620b36 100644
--- a/blimp/client/feature/compositor/blimp_layer_tree_settings.cc
+++ b/blimp/client/feature/compositor/blimp_layer_tree_settings.cc
@@ -66,12 +66,13 @@ void PopulateCommonLayerTreeSettings(cc::LayerTreeSettings* settings) {
   settings->renderer_settings.highp_threshold_min = 2048;
   settings->ignore_root_layer_flings = false;
   bool use_low_memory_policy = base::SysInfo::IsLowEndDevice();
-  settings->renderer_settings.use_rgba_4444_textures = use_low_memory_policy;
   if (use_low_memory_policy) {
     // On low-end we want to be very carefull about killing other
     // apps. So initially we use 50% more memory to avoid flickering
     // or raster-on-demand.
     settings->max_memory_for_prepaint_percentage = 67;
+
+    settings->renderer_settings.preferred_tile_format = cc::RGBA_4444;
   } else {
     // On other devices we have increased memory excessively to avoid
     // raster-on-demand already, so now we reserve 50% _only_ to avoid
diff --git a/cc/base/switches.cc b/cc/base/switches.cc
index 4e02de1..25565b1 100644
--- a/cc/base/switches.cc
+++ b/cc/base/switches.cc
@@ -45,6 +45,9 @@ const char kSlowDownRasterScaleFactor[] = "slow-down-raster-scale-factor";
 const char kStrictLayerPropertyChangeChecking[] =
     "strict-layer-property-change-checking";
 
+// Compress tile textures for GPUs supporting it.
+const char kEnableTileCompression[] = "enable-tile-compression";
+
 // Use a BeginFrame signal from browser to renderer to schedule rendering.
 const char kEnableBeginFrameScheduling[] = "enable-begin-frame-scheduling";
 
diff --git a/cc/base/switches.h b/cc/base/switches.h
index 63d806c..0713053 100644
--- a/cc/base/switches.h
+++ b/cc/base/switches.h
@@ -25,6 +25,7 @@ CC_EXPORT extern const char kTopControlsHideThreshold[];
 CC_EXPORT extern const char kTopControlsShowThreshold[];
 CC_EXPORT extern const char kSlowDownRasterScaleFactor[];
 CC_EXPORT extern const char kStrictLayerPropertyChangeChecking[];
+CC_EXPORT extern const char kEnableTileCompression[];
 
 // Switches for both the renderer and ui compositors.
 CC_EXPORT extern const char kEnableBeginFrameScheduling[];
diff --git a/cc/layers/picture_layer_impl.cc b/cc/layers/picture_layer_impl.cc
index 93d9bf1..695f539 100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -52,6 +52,10 @@ const int kMinHeightForGpuRasteredTile = 256;
 // of using the same tile size.
 const int kTileRoundUp = 64;
 
+// For performance reasons and to support compressed tile textures, tile
+// width and height should be an even multiple of 4 in size.
+const int kTileMinimalAlignment = 4;
+
 }  // namespace
 
 namespace cc {
@@ -781,6 +785,10 @@ gfx::Size PictureLayerImpl::CalculateTileSize(
     tile_height = std::min(tile_height, default_tile_height);
   }
 
+  // Ensure that tile width and height are properly aligned.
+  tile_width = MathUtil::UncheckedRoundUp(tile_width, kTileMinimalAlignment);
+  tile_height = MathUtil::UncheckedRoundUp(tile_height, kTileMinimalAlignment);
+
   // Under no circumstance should we be larger than the max texture size.
   tile_width = std::min(tile_width, max_texture_size);
   tile_height = std::min(tile_height, max_texture_size);
diff --git a/cc/layers/picture_layer_impl_unittest.cc b/cc/layers/picture_layer_impl_unittest.cc
index 0f73ef1..04bac67 100644
--- a/cc/layers/picture_layer_impl_unittest.cc
+++ b/cc/layers/picture_layer_impl_unittest.cc
@@ -4890,8 +4890,10 @@ TEST_F(TileSizeTest, TileSizes) {
 
   layer->set_gpu_raster_max_texture_size(host_impl_.device_viewport_size());
   result = layer->CalculateTileSize(gfx::Size(10000, 10000));
-  EXPECT_EQ(result.width(), 2000 + 2 * PictureLayerTiling::kBorderTexels);
-  EXPECT_EQ(result.height(), 500 + 2);
+  EXPECT_EQ(result.width(),
+            MathUtil::UncheckedRoundUp(
+                2000 + 2 * PictureLayerTiling::kBorderTexels, 4));
+  EXPECT_EQ(result.height(), 504);  // 500 + 2, 4-byte aligned.
 
   // Clamp and round-up, when smaller than viewport.
   // Tile-height doubles to 50% when width shrinks to <= 50%.
@@ -4899,7 +4901,7 @@ TEST_F(TileSizeTest, TileSizes) {
   layer->set_gpu_raster_max_texture_size(host_impl_.device_viewport_size());
   result = layer->CalculateTileSize(gfx::Size(447, 10000));
   EXPECT_EQ(result.width(), 448);
-  EXPECT_EQ(result.height(), 500 + 2);
+  EXPECT_EQ(result.height(), 504);  // 500 + 2, 4-byte aliged.
 
   // Largest layer is 50% of viewport width (rounded up), and
   // 50% of viewport in height.
@@ -4908,7 +4910,7 @@ TEST_F(TileSizeTest, TileSizes) {
   EXPECT_EQ(result.height(), 448);
   result = layer->CalculateTileSize(gfx::Size(500, 499));
   EXPECT_EQ(result.width(), 512);
-  EXPECT_EQ(result.height(), 500 + 2);
+  EXPECT_EQ(result.height(), 504);  // 500 + 2, 4-byte aligned.
 }
 
 TEST_F(NoLowResPictureLayerImplTest, LowResWasHighResCollision) {
diff --git a/cc/output/renderer_settings.cc b/cc/output/renderer_settings.cc
index 133fb33..c0927cc 100644
--- a/cc/output/renderer_settings.cc
+++ b/cc/output/renderer_settings.cc
@@ -8,6 +8,7 @@
 
 #include "base/logging.h"
 #include "cc/proto/renderer_settings.pb.h"
+#include "cc/resources/platform_color.h"
 
 namespace cc {
 
@@ -22,9 +23,9 @@ RendererSettings::RendererSettings()
       release_overlay_resources_on_swap_complete(false),
       refresh_rate(60.0),
       highp_threshold_min(0),
-      use_rgba_4444_textures(false),
       texture_id_allocation_chunk_size(64),
-      use_gpu_memory_buffer_resources(false) {}
+      use_gpu_memory_buffer_resources(false),
+      preferred_tile_format(PlatformColor::BestTextureFormat()) {}
 
 RendererSettings::~RendererSettings() {
 }
@@ -41,9 +42,9 @@ void RendererSettings::ToProtobuf(proto::RendererSettings* proto) const {
       release_overlay_resources_on_swap_complete);
   proto->set_refresh_rate(refresh_rate);
   proto->set_highp_threshold_min(highp_threshold_min);
-  proto->set_use_rgba_4444_textures(use_rgba_4444_textures);
   proto->set_texture_id_allocation_chunk_size(texture_id_allocation_chunk_size);
   proto->set_use_gpu_memory_buffer_resources(use_gpu_memory_buffer_resources);
+  proto->set_preferred_tile_format(preferred_tile_format);
 }
 
 void RendererSettings::FromProtobuf(const proto::RendererSettings& proto) {
@@ -58,9 +59,13 @@ void RendererSettings::FromProtobuf(const proto::RendererSettings& proto) {
       proto.release_overlay_resources_on_swap_complete();
   refresh_rate = proto.refresh_rate();
   highp_threshold_min = proto.highp_threshold_min();
-  use_rgba_4444_textures = proto.use_rgba_4444_textures();
   texture_id_allocation_chunk_size = proto.texture_id_allocation_chunk_size();
   use_gpu_memory_buffer_resources = proto.use_gpu_memory_buffer_resources();
+
+  DCHECK_LE(proto.preferred_tile_format(),
+            static_cast<uint32_t>(RESOURCE_FORMAT_MAX));
+  preferred_tile_format =
+      static_cast<ResourceFormat>(proto.preferred_tile_format());
 }
 
 bool RendererSettings::operator==(const RendererSettings& other) const {
@@ -75,11 +80,11 @@ bool RendererSettings::operator==(const RendererSettings& other) const {
              other.release_overlay_resources_on_swap_complete &&
          refresh_rate == other.refresh_rate &&
          highp_threshold_min == other.highp_threshold_min &&
-         use_rgba_4444_textures == other.use_rgba_4444_textures &&
          texture_id_allocation_chunk_size ==
              other.texture_id_allocation_chunk_size &&
          use_gpu_memory_buffer_resources ==
-             other.use_gpu_memory_buffer_resources;
+             other.use_gpu_memory_buffer_resources &&
+         preferred_tile_format == other.preferred_tile_format;
 }
 
 }  // namespace cc
diff --git a/cc/output/renderer_settings.h b/cc/output/renderer_settings.h
index 657996e..5aeaee6 100644
--- a/cc/output/renderer_settings.h
+++ b/cc/output/renderer_settings.h
@@ -8,6 +8,7 @@
 #include <stddef.h>
 
 #include "cc/base/cc_export.h"
+#include "cc/resources/resource_format.h"
 
 namespace cc {
 
@@ -30,9 +31,9 @@ class CC_EXPORT RendererSettings {
   bool release_overlay_resources_on_swap_complete;
   double refresh_rate;
   int highp_threshold_min;
-  bool use_rgba_4444_textures;
   size_t texture_id_allocation_chunk_size;
   bool use_gpu_memory_buffer_resources;
+  ResourceFormat preferred_tile_format;
 
   void ToProtobuf(proto::RendererSettings* proto) const;
   void FromProtobuf(const proto::RendererSettings& proto);
diff --git a/cc/output/renderer_settings_unittest.cc b/cc/output/renderer_settings_unittest.cc
index ca318ae..281c278 100644
--- a/cc/output/renderer_settings_unittest.cc
+++ b/cc/output/renderer_settings_unittest.cc
@@ -30,9 +30,9 @@ TEST(RendererSettingsTest, AllFieldsFlipped) {
   settings.release_overlay_resources_on_swap_complete = true;
   settings.refresh_rate = 6.0;
   settings.highp_threshold_min = 1;
-  settings.use_rgba_4444_textures = true;
   settings.texture_id_allocation_chunk_size = 46;
   settings.use_gpu_memory_buffer_resources = true;
+  settings.preferred_tile_format = RGBA_4444;
   VerifySerializeAndDeserializeProto(settings);
 }
 
@@ -48,9 +48,9 @@ TEST(RendererSettingsTest, ArbitraryFieldValues) {
   settings.release_overlay_resources_on_swap_complete = true;
   settings.refresh_rate = 999.0;
   settings.highp_threshold_min = 1;
-  settings.use_rgba_4444_textures = true;
   settings.texture_id_allocation_chunk_size = 12;
   settings.use_gpu_memory_buffer_resources = true;
+  settings.preferred_tile_format = RGBA_4444;
   VerifySerializeAndDeserializeProto(settings);
 }
 
diff --git a/cc/proto/renderer_settings.proto b/cc/proto/renderer_settings.proto
index c439934..753de48 100644
--- a/cc/proto/renderer_settings.proto
+++ b/cc/proto/renderer_settings.proto
@@ -19,7 +19,7 @@ message RendererSettings {
   optional bool release_overlay_resources_on_swap_complete = 8;
   optional double refresh_rate = 9;
   optional uint32 highp_threshold_min = 10;
-  optional bool use_rgba_4444_textures = 11;
-  optional uint32 texture_id_allocation_chunk_size = 12;
-  optional bool use_gpu_memory_buffer_resources = 13;
+  optional uint32 texture_id_allocation_chunk_size = 11;
+  optional bool use_gpu_memory_buffer_resources = 12;
+  optional uint32 preferred_tile_format = 13;
 }
diff --git a/cc/raster/one_copy_tile_task_worker_pool.cc b/cc/raster/one_copy_tile_task_worker_pool.cc
index 1252205..38e3076 100644
--- a/cc/raster/one_copy_tile_task_worker_pool.cc
+++ b/cc/raster/one_copy_tile_task_worker_pool.cc
@@ -185,11 +185,11 @@ scoped_ptr<TileTaskWorkerPool> OneCopyTileTaskWorkerPool::Create(
     int max_copy_texture_chromium_size,
     bool use_partial_raster,
     int max_staging_buffer_usage_in_bytes,
-    bool use_rgba_4444_texture_format) {
+    ResourceFormat preferred_tile_format) {
   return make_scoped_ptr<TileTaskWorkerPool>(new OneCopyTileTaskWorkerPool(
       task_runner, task_graph_runner, resource_provider,
       max_copy_texture_chromium_size, use_partial_raster,
-      max_staging_buffer_usage_in_bytes, use_rgba_4444_texture_format));
+      max_staging_buffer_usage_in_bytes, preferred_tile_format));
 }
 
 OneCopyTileTaskWorkerPool::OneCopyTileTaskWorkerPool(
@@ -199,7 +199,7 @@ OneCopyTileTaskWorkerPool::OneCopyTileTaskWorkerPool(
     int max_copy_texture_chromium_size,
     bool use_partial_raster,
     int max_staging_buffer_usage_in_bytes,
-    bool use_rgba_4444_texture_format)
+    ResourceFormat preferred_tile_format)
     : task_runner_(task_runner),
       task_graph_runner_(task_graph_runner),
       namespace_token_(task_graph_runner->GetNamespaceToken()),
@@ -212,7 +212,7 @@ OneCopyTileTaskWorkerPool::OneCopyTileTaskWorkerPool(
       use_partial_raster_(use_partial_raster),
       bytes_scheduled_since_last_flush_(0),
       max_staging_buffer_usage_in_bytes_(max_staging_buffer_usage_in_bytes),
-      use_rgba_4444_texture_format_(use_rgba_4444_texture_format),
+      preferred_tile_format_(preferred_tile_format),
       staging_buffer_usage_in_bytes_(0),
       free_staging_buffer_usage_in_bytes_(0),
       staging_buffer_expiration_delay_(
@@ -285,9 +285,13 @@ void OneCopyTileTaskWorkerPool::CheckForCompletedTasks() {
 
 ResourceFormat OneCopyTileTaskWorkerPool::GetResourceFormat(
     bool must_support_alpha) const {
-  return use_rgba_4444_texture_format_
-             ? RGBA_4444
-             : resource_provider_->best_texture_format();
+  if (resource_provider_->IsResourceFormatSupported(preferred_tile_format_) &&
+      (DoesResourceFormatSupportAlpha(preferred_tile_format_) ||
+       !must_support_alpha)) {
+    return preferred_tile_format_;
+  }
+
+  return resource_provider_->best_texture_format();
 }
 
 bool OneCopyTileTaskWorkerPool::GetResourceRequiresSwizzle(
@@ -427,31 +431,39 @@ void OneCopyTileTaskWorkerPool::PlaybackAndCopyOnWorkerThread(
 #endif
     }
 
-    int bytes_per_row =
-        (BitsPerPixel(resource->format()) * resource->size().width()) / 8;
-    int chunk_size_in_rows =
-        std::max(1, max_bytes_per_copy_operation_ / bytes_per_row);
-    // Align chunk size to 4. Required to support compressed texture formats.
-    chunk_size_in_rows = MathUtil::UncheckedRoundUp(chunk_size_in_rows, 4);
-    int y = 0;
-    int height = resource->size().height();
-    while (y < height) {
-      // Copy at most |chunk_size_in_rows|.
-      int rows_to_copy = std::min(chunk_size_in_rows, height - y);
-      DCHECK_GT(rows_to_copy, 0);
-
-      gl->CopySubTextureCHROMIUM(
-          staging_buffer->texture_id, resource_lock->texture_id(), 0, y, 0, y,
-          resource->size().width(), rows_to_copy, false, false, false);
-      y += rows_to_copy;
-
-      // Increment |bytes_scheduled_since_last_flush_| by the amount of memory
-      // used for this copy operation.
-      bytes_scheduled_since_last_flush_ += rows_to_copy * bytes_per_row;
-
-      if (bytes_scheduled_since_last_flush_ >= max_bytes_per_copy_operation_) {
-        gl->ShallowFlushCHROMIUM();
-        bytes_scheduled_since_last_flush_ = 0;
+    // Since compressed texture's cannot be pre-allocated we might have an
+    // unallocated resource in which case we need to perform a full size copy.
+    if (IsResourceFormatCompressed(resource->format())) {
+      gl->CompressedCopyTextureCHROMIUM(staging_buffer->texture_id,
+                                        resource_lock->texture_id());
+    } else {
+      int bytes_per_row =
+          (BitsPerPixel(resource->format()) * resource->size().width()) / 8;
+      int chunk_size_in_rows =
+          std::max(1, max_bytes_per_copy_operation_ / bytes_per_row);
+      // Align chunk size to 4. Required to support compressed texture formats.
+      chunk_size_in_rows = MathUtil::UncheckedRoundUp(chunk_size_in_rows, 4);
+      int y = 0;
+      int height = resource->size().height();
+      while (y < height) {
+        // Copy at most |chunk_size_in_rows|.
+        int rows_to_copy = std::min(chunk_size_in_rows, height - y);
+        DCHECK_GT(rows_to_copy, 0);
+
+        gl->CopySubTextureCHROMIUM(
+            staging_buffer->texture_id, resource_lock->texture_id(), 0, y, 0, y,
+            resource->size().width(), rows_to_copy, false, false, false);
+        y += rows_to_copy;
+
+        // Increment |bytes_scheduled_since_last_flush_| by the amount of memory
+        // used for this copy operation.
+        bytes_scheduled_since_last_flush_ += rows_to_copy * bytes_per_row;
+
+        if (bytes_scheduled_since_last_flush_ >=
+            max_bytes_per_copy_operation_) {
+          gl->ShallowFlushCHROMIUM();
+          bytes_scheduled_since_last_flush_ = 0;
+        }
       }
     }
 
diff --git a/cc/raster/one_copy_tile_task_worker_pool.h b/cc/raster/one_copy_tile_task_worker_pool.h
index 581c57b..3a9187e 100644
--- a/cc/raster/one_copy_tile_task_worker_pool.h
+++ b/cc/raster/one_copy_tile_task_worker_pool.h
@@ -53,7 +53,7 @@ class CC_EXPORT OneCopyTileTaskWorkerPool
       int max_copy_texture_chromium_size,
       bool use_partial_raster,
       int max_staging_buffer_usage_in_bytes,
-      bool use_rgba_4444_texture_format);
+      ResourceFormat preferred_tile_format);
 
   // Overridden from TileTaskWorkerPool:
   TileTaskRunner* AsTileTaskRunner() override;
@@ -95,7 +95,7 @@ class CC_EXPORT OneCopyTileTaskWorkerPool
                             int max_copy_texture_chromium_size,
                             bool use_partial_raster,
                             int max_staging_buffer_usage_in_bytes,
-                            bool use_rgba_4444_texture_format);
+                            ResourceFormat preferred_tile_format);
 
  private:
   struct StagingBuffer {
@@ -152,7 +152,7 @@ class CC_EXPORT OneCopyTileTaskWorkerPool
   StagingBufferDeque busy_buffers_;
   int bytes_scheduled_since_last_flush_;
   const int max_staging_buffer_usage_in_bytes_;
-  bool use_rgba_4444_texture_format_;
+  ResourceFormat preferred_tile_format_;
   int staging_buffer_usage_in_bytes_;
   int free_staging_buffer_usage_in_bytes_;
   const base::TimeDelta staging_buffer_expiration_delay_;
diff --git a/cc/raster/tile_task_worker_pool.cc b/cc/raster/tile_task_worker_pool.cc
index d4549c7..b746d22 100644
--- a/cc/raster/tile_task_worker_pool.cc
+++ b/cc/raster/tile_task_worker_pool.cc
@@ -8,6 +8,7 @@
 
 #include "base/trace_event/trace_event.h"
 #include "cc/playback/display_list_raster_source.h"
+#include "cc/raster/texture_compressor.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkSurface.h"
@@ -44,11 +45,11 @@ bool IsSupportedPlaybackToMemoryFormat(ResourceFormat format) {
     case RGBA_4444:
     case RGBA_8888:
     case BGRA_8888:
+    case ETC1:
       return true;
     case ALPHA_8:
     case LUMINANCE_8:
     case RGB_565:
-    case ETC1:
     case RED_8:
     case LUMINANCE_F16:
       return false;
@@ -116,8 +117,6 @@ void TileTaskWorkerPool::PlaybackToMemory(
   // Uses kPremul_SkAlphaType since the result is not known to be opaque.
   SkImageInfo info =
       SkImageInfo::MakeN32(size.width(), size.height(), kPremul_SkAlphaType);
-  SkColorType buffer_color_type = ResourceFormatToSkColorType(format);
-  bool needs_copy = buffer_color_type != info.colorType();
 
   // Use unknown pixel geometry to disable LCD text.
   SkSurfaceProps surface_props(0, kUnknown_SkPixelGeometry);
@@ -130,31 +129,59 @@ void TileTaskWorkerPool::PlaybackToMemory(
     stride = info.minRowBytes();
   DCHECK_GT(stride, 0u);
 
-  if (!needs_copy) {
-    skia::RefPtr<SkSurface> surface = skia::AdoptRef(
-        SkSurface::NewRasterDirect(info, memory, stride, &surface_props));
-    AutoSkipImageCanvas canvas(surface->getCanvas(), include_images);
-    raster_source->PlaybackToCanvas(canvas, canvas_bitmap_rect,
-                                    canvas_playback_rect, scale);
-    return;
-  }
-
-  skia::RefPtr<SkSurface> surface =
-      skia::AdoptRef(SkSurface::NewRaster(info, &surface_props));
-  AutoSkipImageCanvas canvas(surface->getCanvas(), include_images);
-  // TODO(reveman): Improve partial raster support by reducing the size of
-  // playback rect passed to PlaybackToCanvas. crbug.com/519070
-  raster_source->PlaybackToCanvas(canvas, canvas_bitmap_rect,
-                                  canvas_bitmap_rect, scale);
-
   {
     TRACE_EVENT0("cc", "TileTaskWorkerPool::PlaybackToMemory::ConvertPixels");
 
-    SkImageInfo dst_info =
-        SkImageInfo::Make(info.width(), info.height(), buffer_color_type,
-                          info.alphaType(), info.profileType());
-    bool rv = surface->getCanvas()->readPixels(dst_info, memory, stride, 0, 0);
-    DCHECK(rv);
+    switch (format) {
+      case RGBA_8888:
+      case BGRA_8888: {
+        skia::RefPtr<SkSurface> surface = skia::AdoptRef(
+            SkSurface::NewRasterDirect(info, memory, stride, &surface_props));
+        AutoSkipImageCanvas canvas(surface->getCanvas(), include_images);
+        raster_source->PlaybackToCanvas(canvas, canvas_bitmap_rect,
+                                        canvas_playback_rect, scale);
+        return;
+      }
+      case RGBA_4444:
+      case ETC1: {
+        skia::RefPtr<SkSurface> surface =
+            skia::AdoptRef(SkSurface::NewRaster(info, &surface_props));
+        AutoSkipImageCanvas canvas(surface->getCanvas(), include_images);
+        // TODO(reveman): Improve partial raster support by reducing the size of
+        // playback rect passed to PlaybackToCanvas. crbug.com/519070
+        raster_source->PlaybackToCanvas(canvas, canvas_bitmap_rect,
+                                        canvas_bitmap_rect, scale);
+
+        if (format == ETC1) {
+          DCHECK_EQ(size.width() % 4, 0);
+          DCHECK_EQ(size.height() % 4, 0);
+          scoped_ptr<TextureCompressor> texture_compressor =
+              TextureCompressor::Create(TextureCompressor::kFormatETC1);
+          texture_compressor->Compress(
+              reinterpret_cast<const uint8_t*>(
+                  surface->peekPixels(nullptr, nullptr)),
+              reinterpret_cast<uint8_t*>(memory), size.width(), size.height(),
+              TextureCompressor::kQualityHigh);
+        } else {
+          SkImageInfo dst_info = SkImageInfo::Make(
+              info.width(), info.height(), ResourceFormatToSkColorType(format),
+              info.alphaType(), info.profileType());
+          bool rv =
+              surface->getCanvas()->readPixels(dst_info, memory, stride, 0, 0);
+          DCHECK(rv);
+        }
+        return;
+      }
+      case ALPHA_8:
+      case LUMINANCE_8:
+      case RGB_565:
+      case RED_8:
+      case LUMINANCE_F16:
+        NOTREACHED();
+        return;
+    }
+
+    NOTREACHED();
   }
 }
 
diff --git a/cc/raster/tile_task_worker_pool_perftest.cc b/cc/raster/tile_task_worker_pool_perftest.cc
index 0abdf8e..086d7b1 100644
--- a/cc/raster/tile_task_worker_pool_perftest.cc
+++ b/cc/raster/tile_task_worker_pool_perftest.cc
@@ -259,7 +259,7 @@ class TileTaskWorkerPoolPerfTest
         Create3dOutputSurfaceAndResourceProvider();
         tile_task_worker_pool_ = ZeroCopyTileTaskWorkerPool::Create(
             task_runner_.get(), task_graph_runner_.get(),
-            resource_provider_.get(), false);
+            resource_provider_.get(), PlatformColor::BestTextureFormat());
         break;
       case TILE_TASK_WORKER_POOL_TYPE_ONE_COPY:
         Create3dOutputSurfaceAndResourceProvider();
@@ -267,7 +267,8 @@ class TileTaskWorkerPoolPerfTest
             task_runner_.get(), task_graph_runner_.get(),
             context_provider_.get(), resource_provider_.get(),
             std::numeric_limits<int>::max(), false,
-            std::numeric_limits<int>::max(), false);
+            std::numeric_limits<int>::max(),
+            PlatformColor::BestTextureFormat());
         break;
       case TILE_TASK_WORKER_POOL_TYPE_GPU:
         Create3dOutputSurfaceAndResourceProvider();
diff --git a/cc/raster/tile_task_worker_pool_unittest.cc b/cc/raster/tile_task_worker_pool_unittest.cc
index 9f8b003..2473629e 100644
--- a/cc/raster/tile_task_worker_pool_unittest.cc
+++ b/cc/raster/tile_task_worker_pool_unittest.cc
@@ -147,14 +147,15 @@ class TileTaskWorkerPoolTest
         Create3dOutputSurfaceAndResourceProvider();
         tile_task_worker_pool_ = ZeroCopyTileTaskWorkerPool::Create(
             base::ThreadTaskRunnerHandle::Get().get(), &task_graph_runner_,
-            resource_provider_.get(), false);
+            resource_provider_.get(), PlatformColor::BestTextureFormat());
         break;
       case TILE_TASK_WORKER_POOL_TYPE_ONE_COPY:
         Create3dOutputSurfaceAndResourceProvider();
         tile_task_worker_pool_ = OneCopyTileTaskWorkerPool::Create(
             base::ThreadTaskRunnerHandle::Get().get(), &task_graph_runner_,
             context_provider_.get(), resource_provider_.get(),
-            kMaxBytesPerCopyOperation, false, kMaxStagingBuffers, false);
+            kMaxBytesPerCopyOperation, false, kMaxStagingBuffers,
+            PlatformColor::BestTextureFormat());
         break;
       case TILE_TASK_WORKER_POOL_TYPE_GPU:
         Create3dOutputSurfaceAndResourceProvider();
diff --git a/cc/raster/zero_copy_tile_task_worker_pool.cc b/cc/raster/zero_copy_tile_task_worker_pool.cc
index 4310f96..1fd8e3d 100644
--- a/cc/raster/zero_copy_tile_task_worker_pool.cc
+++ b/cc/raster/zero_copy_tile_task_worker_pool.cc
@@ -68,22 +68,22 @@ scoped_ptr<TileTaskWorkerPool> ZeroCopyTileTaskWorkerPool::Create(
     base::SequencedTaskRunner* task_runner,
     TaskGraphRunner* task_graph_runner,
     ResourceProvider* resource_provider,
-    bool use_rgba_4444_texture_format) {
-  return make_scoped_ptr<TileTaskWorkerPool>(new ZeroCopyTileTaskWorkerPool(
-      task_runner, task_graph_runner, resource_provider,
-      use_rgba_4444_texture_format));
+    ResourceFormat preferred_tile_format) {
+  return make_scoped_ptr<TileTaskWorkerPool>(
+      new ZeroCopyTileTaskWorkerPool(task_runner, task_graph_runner,
+                                     resource_provider, preferred_tile_format));
 }
 
 ZeroCopyTileTaskWorkerPool::ZeroCopyTileTaskWorkerPool(
     base::SequencedTaskRunner* task_runner,
     TaskGraphRunner* task_graph_runner,
     ResourceProvider* resource_provider,
-    bool use_rgba_4444_texture_format)
+    ResourceFormat preferred_tile_format)
     : task_runner_(task_runner),
       task_graph_runner_(task_graph_runner),
       namespace_token_(task_graph_runner->GetNamespaceToken()),
       resource_provider_(resource_provider),
-      use_rgba_4444_texture_format_(use_rgba_4444_texture_format) {}
+      preferred_tile_format_(preferred_tile_format) {}
 
 ZeroCopyTileTaskWorkerPool::~ZeroCopyTileTaskWorkerPool() {
 }
@@ -125,9 +125,13 @@ void ZeroCopyTileTaskWorkerPool::CheckForCompletedTasks() {
 
 ResourceFormat ZeroCopyTileTaskWorkerPool::GetResourceFormat(
     bool must_support_alpha) const {
-  return use_rgba_4444_texture_format_
-             ? RGBA_4444
-             : resource_provider_->best_texture_format();
+  if (resource_provider_->IsResourceFormatSupported(preferred_tile_format_) &&
+      (DoesResourceFormatSupportAlpha(preferred_tile_format_) ||
+       !must_support_alpha)) {
+    return preferred_tile_format_;
+  }
+
+  return resource_provider_->best_texture_format();
 }
 
 bool ZeroCopyTileTaskWorkerPool::GetResourceRequiresSwizzle(
diff --git a/cc/raster/zero_copy_tile_task_worker_pool.h b/cc/raster/zero_copy_tile_task_worker_pool.h
index ffbde20..a961e41 100644
--- a/cc/raster/zero_copy_tile_task_worker_pool.h
+++ b/cc/raster/zero_copy_tile_task_worker_pool.h
@@ -32,7 +32,7 @@ class CC_EXPORT ZeroCopyTileTaskWorkerPool : public TileTaskWorkerPool,
       base::SequencedTaskRunner* task_runner,
       TaskGraphRunner* task_graph_runner,
       ResourceProvider* resource_provider,
-      bool use_rgba_4444_texture_format);
+      ResourceFormat preferred_tile_format);
 
   // Overridden from TileTaskWorkerPool:
   TileTaskRunner* AsTileTaskRunner() override;
@@ -55,7 +55,7 @@ class CC_EXPORT ZeroCopyTileTaskWorkerPool : public TileTaskWorkerPool,
   ZeroCopyTileTaskWorkerPool(base::SequencedTaskRunner* task_runner,
                              TaskGraphRunner* task_graph_runner,
                              ResourceProvider* resource_provider,
-                             bool use_rgba_4444_texture_format);
+                             ResourceFormat preferred_tile_format);
 
  private:
   scoped_refptr<base::trace_event::ConvertableToTraceFormat> StateAsValue()
@@ -66,7 +66,7 @@ class CC_EXPORT ZeroCopyTileTaskWorkerPool : public TileTaskWorkerPool,
   const NamespaceToken namespace_token_;
   ResourceProvider* resource_provider_;
 
-  bool use_rgba_4444_texture_format_;
+  ResourceFormat preferred_tile_format_;
 
   Task::Vector completed_tasks_;
 
diff --git a/cc/resources/platform_color.h b/cc/resources/platform_color.h
index f7d3705..26d6b02 100644
--- a/cc/resources/platform_color.h
+++ b/cc/resources/platform_color.h
@@ -24,7 +24,19 @@ class PlatformColor {
   }
 
   // Returns the most efficient texture format for this platform.
-  static ResourceFormat BestTextureFormat(bool supports_bgra8888) {
+  static ResourceFormat BestTextureFormat() {
+    switch (Format()) {
+      case SOURCE_FORMAT_BGRA8:
+        return BGRA_8888;
+      case SOURCE_FORMAT_RGBA8:
+        return RGBA_8888;
+    }
+    NOTREACHED();
+    return RGBA_8888;
+  }
+
+  // Returns the most efficient supported texture format for this platform.
+  static ResourceFormat BestSupportedTextureFormat(bool supports_bgra8888) {
     switch (Format()) {
       case SOURCE_FORMAT_BGRA8:
         return (supports_bgra8888) ? BGRA_8888 : RGBA_8888;
diff --git a/cc/resources/resource_format.cc b/cc/resources/resource_format.cc
index ba4e65d..ec553d8 100644
--- a/cc/resources/resource_format.cc
+++ b/cc/resources/resource_format.cc
@@ -101,10 +101,11 @@ gfx::BufferFormat BufferFormat(ResourceFormat format) {
       return gfx::BufferFormat::RGBA_4444;
     case RGBA_8888:
       return gfx::BufferFormat::RGBA_8888;
+    case ETC1:
+      return gfx::BufferFormat::ETC1;
     case ALPHA_8:
     case LUMINANCE_8:
     case RGB_565:
-    case ETC1:
     case LUMINANCE_F16:
       break;
   }
@@ -112,4 +113,26 @@ gfx::BufferFormat BufferFormat(ResourceFormat format) {
   return gfx::BufferFormat::RGBA_8888;
 }
 
+bool IsResourceFormatCompressed(ResourceFormat format) {
+  return format == ETC1;
+}
+
+bool DoesResourceFormatSupportAlpha(ResourceFormat format) {
+  switch (format) {
+    case RGBA_4444:
+    case RGBA_8888:
+    case BGRA_8888:
+    case ALPHA_8:
+      return true;
+    case LUMINANCE_8:
+    case RGB_565:
+    case ETC1:
+    case RED_8:
+    case LUMINANCE_F16:
+      return false;
+  }
+  NOTREACHED();
+  return false;
+}
+
 }  // namespace cc
diff --git a/cc/resources/resource_format.h b/cc/resources/resource_format.h
index 9a900d4..5266f31 100644
--- a/cc/resources/resource_format.h
+++ b/cc/resources/resource_format.h
@@ -39,6 +39,9 @@ CC_EXPORT GLenum GLDataFormat(ResourceFormat format);
 CC_EXPORT GLenum GLInternalFormat(ResourceFormat format);
 CC_EXPORT gfx::BufferFormat BufferFormat(ResourceFormat format);
 
+bool IsResourceFormatCompressed(ResourceFormat format);
+bool DoesResourceFormatSupportAlpha(ResourceFormat format);
+
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_FORMAT_H_
diff --git a/cc/resources/resource_provider.cc b/cc/resources/resource_provider.cc
index 98354a1..8913b0c 100644
--- a/cc/resources/resource_provider.cc
+++ b/cc/resources/resource_provider.cc
@@ -425,6 +425,32 @@ ResourceProvider::~ResourceProvider() {
   gl->Finish();
 }
 
+bool ResourceProvider::IsResourceFormatSupported(ResourceFormat format) const {
+  ContextProvider::Capabilities caps;
+  if (output_surface_->context_provider())
+    caps = output_surface_->context_provider()->ContextCapabilities();
+
+  switch (format) {
+    case ALPHA_8:
+    case RGBA_4444:
+    case RGBA_8888:
+    case RGB_565:
+    case LUMINANCE_8:
+      return true;
+    case BGRA_8888:
+      return caps.gpu.texture_format_bgra8888;
+    case ETC1:
+      return caps.gpu.texture_format_etc1;
+    case RED_8:
+      return caps.gpu.texture_rg;
+    case LUMINANCE_F16:
+      return caps.gpu.texture_half_float_linear;
+  }
+
+  NOTREACHED();
+  return false;
+}
+
 bool ResourceProvider::InUseByConsumer(ResourceId id) {
   Resource* resource = GetResource(id);
   return resource->lock_for_read_count > 0 || resource->exported_count > 0 ||
@@ -1220,10 +1246,10 @@ void ResourceProvider::Initialize() {
   max_texture_size_ = 0;  // Context expects cleared value.
   gl->GetIntegerv(GL_MAX_TEXTURE_SIZE, &max_texture_size_);
   best_texture_format_ =
-      PlatformColor::BestTextureFormat(use_texture_format_bgra_);
+      PlatformColor::BestSupportedTextureFormat(use_texture_format_bgra_);
 
-  best_render_buffer_format_ =
-      PlatformColor::BestTextureFormat(caps.gpu.render_buffer_format_bgra8888);
+  best_render_buffer_format_ = PlatformColor::BestSupportedTextureFormat(
+      caps.gpu.render_buffer_format_bgra8888);
 
   texture_id_allocator_.reset(
       new TextureIdAllocator(gl, id_allocation_chunk_size_));
diff --git a/cc/resources/resource_provider.h b/cc/resources/resource_provider.h
index ea5b3e1..a033967 100644
--- a/cc/resources/resource_provider.h
+++ b/cc/resources/resource_provider.h
@@ -111,6 +111,8 @@ class CC_EXPORT ResourceProvider
   }
   size_t num_resources() const { return resources_.size(); }
 
+  bool IsResourceFormatSupported(ResourceFormat format) const;
+
   // Checks whether a resource is in use by a consumer.
   bool InUseByConsumer(ResourceId id);
 
diff --git a/cc/test/layer_tree_pixel_resource_test.cc b/cc/test/layer_tree_pixel_resource_test.cc
index 347933c..5d810ab 100644
--- a/cc/test/layer_tree_pixel_resource_test.cc
+++ b/cc/test/layer_tree_pixel_resource_test.cc
@@ -147,7 +147,8 @@ void LayerTreeHostPixelResourceTest::CreateResourceAndTileTaskWorkerPool(
       *resource_pool = ResourcePool::Create(resource_provider, task_runner);
 
       *tile_task_worker_pool = ZeroCopyTileTaskWorkerPool::Create(
-          task_runner, task_graph_runner(), resource_provider, false);
+          task_runner, task_graph_runner(), resource_provider,
+          PlatformColor::BestTextureFormat());
       break;
     case ONE_COPY_TILE_TASK_WORKER_POOL:
       EXPECT_TRUE(context_provider);
@@ -158,7 +159,8 @@ void LayerTreeHostPixelResourceTest::CreateResourceAndTileTaskWorkerPool(
       *tile_task_worker_pool = OneCopyTileTaskWorkerPool::Create(
           task_runner, task_graph_runner(), context_provider, resource_provider,
           max_bytes_per_copy_operation, false,
-          max_staging_buffer_usage_in_bytes, false);
+          max_staging_buffer_usage_in_bytes,
+          PlatformColor::BestTextureFormat());
       break;
   }
 }
diff --git a/cc/tiles/tile_manager.cc b/cc/tiles/tile_manager.cc
index 63e9968..704df07 100644
--- a/cc/tiles/tile_manager.cc
+++ b/cc/tiles/tile_manager.cc
@@ -833,8 +833,6 @@ scoped_refptr<RasterTask> TileManager::CreateRasterTask(
   if (resource) {
     resource_content_id = tile->invalidated_id();
     DCHECK_EQ(DetermineResourceFormat(tile), resource->format());
-    DCHECK_EQ(tile->desired_texture_size().ToString(),
-              resource->size().ToString());
   } else {
     resource = resource_pool_->AcquireResource(tile->desired_texture_size(),
                                                DetermineResourceFormat(tile));
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index bd759da..1ae252f 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -2226,7 +2226,7 @@ void LayerTreeHostImpl::CreateResourceAndTileTaskWorkerPool(
 
     *tile_task_worker_pool = ZeroCopyTileTaskWorkerPool::Create(
         GetTaskRunner(), task_graph_runner, resource_provider_.get(),
-        settings_.renderer_settings.use_rgba_4444_textures);
+        settings_.renderer_settings.preferred_tile_format);
     return;
   }
 
@@ -2240,7 +2240,7 @@ void LayerTreeHostImpl::CreateResourceAndTileTaskWorkerPool(
       GetTaskRunner(), task_graph_runner, context_provider,
       resource_provider_.get(), max_copy_texture_chromium_size,
       settings_.use_partial_raster, settings_.max_staging_buffer_usage_in_bytes,
-      settings_.renderer_settings.use_rgba_4444_textures);
+      settings_.renderer_settings.preferred_tile_format);
 }
 
 void LayerTreeHostImpl::RecordMainFrameTiming(
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 5e09f0c..2c36b9d 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -1525,6 +1525,7 @@ void RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer(
     cc::switches::kEnableBeginFrameScheduling,
     cc::switches::kEnableGpuBenchmarking,
     cc::switches::kEnableMainFrameBeforeActivation,
+    cc::switches::kEnableTileCompression,
     cc::switches::kShowCompositedLayerBorders,
     cc::switches::kShowFPSCounter,
     cc::switches::kShowLayerAnimationBounds,
diff --git a/content/renderer/gpu/render_widget_compositor.cc b/content/renderer/gpu/render_widget_compositor.cc
index 004addd..2d97eca 100644
--- a/content/renderer/gpu/render_widget_compositor.cc
+++ b/content/renderer/gpu/render_widget_compositor.cc
@@ -406,14 +406,16 @@ void RenderWidgetCompositor::Initialize(float device_scale_factor) {
   // low end, so always use default policy.
   bool use_low_memory_policy =
       base::SysInfo::IsLowEndDevice() && !using_synchronous_compositor;
-  // RGBA_4444 textures are only enabled by default for low end devices
-  // and are disabled for Android WebView as it doesn't support the format.
-  settings.renderer_settings.use_rgba_4444_textures = use_low_memory_policy;
   if (use_low_memory_policy) {
     // On low-end we want to be very carefull about killing other
     // apps. So initially we use 50% more memory to avoid flickering
     // or raster-on-demand.
     settings.max_memory_for_prepaint_percentage = 67;
+
+    // RGBA_4444 textures are only enabled by default for low end devices
+    // and are disabled for Android WebView as it doesn't support the format.
+    if (!cmd->HasSwitch(switches::kDisableRGBA4444Textures))
+      settings.renderer_settings.preferred_tile_format = cc::RGBA_4444;
   } else {
     // On other devices we have increased memory excessively to avoid
     // raster-on-demand already, so now we reserve 50% _only_ to avoid
@@ -449,10 +451,14 @@ void RenderWidgetCompositor::Initialize(float device_scale_factor) {
   if (cmd->HasSwitch(cc::switches::kEnableBeginFrameScheduling))
     settings.use_external_begin_frame_source = true;
 
-  settings.renderer_settings.use_rgba_4444_textures |=
-      cmd->HasSwitch(switches::kEnableRGBA4444Textures);
-  settings.renderer_settings.use_rgba_4444_textures &=
-      !cmd->HasSwitch(switches::kDisableRGBA4444Textures);
+  if (cmd->HasSwitch(switches::kEnableRGBA4444Textures) &&
+      !cmd->HasSwitch(switches::kDisableRGBA4444Textures)) {
+    settings.renderer_settings.preferred_tile_format = cc::RGBA_4444;
+  }
+
+  if (cmd->HasSwitch(cc::switches::kEnableTileCompression)) {
+    settings.renderer_settings.preferred_tile_format = cc::ETC1;
+  }
 
   if (delegate_->ForOOPIF()) {
     // TODO(simonhong): Apply BeginFrame scheduling for OOPIF.
diff --git a/ui/compositor/compositor.cc b/ui/compositor/compositor.cc
index 313e12c..e359f66 100644
--- a/ui/compositor/compositor.cc
+++ b/ui/compositor/compositor.cc
@@ -146,8 +146,8 @@ Compositor::Compositor(ui::ContextFactory* context_factory,
 
   settings.use_zero_copy = IsUIZeroCopyEnabled();
 
-  settings.renderer_settings.use_rgba_4444_textures =
-      command_line->HasSwitch(switches::kUIEnableRGBA4444Textures);
+  if (command_line->HasSwitch(switches::kUIEnableRGBA4444Textures))
+    settings.renderer_settings.preferred_tile_format = cc::RGBA_4444;
 
   // UI compositor always uses partial raster if not using zero-copy. Zero copy
   // doesn't currently support partial raster.