Tile Compression

cc/resources/tile_manager.cc

Index: cc/resources/tile_manager.cc
diff --git a/cc/resources/tile_manager.cc b/cc/resources/tile_manager.cc
index 7ab1fbf98dc3cd340456c1908ab2a6e4dd66b94f..8d80633e859b5006f8dc69e6cf373f54d4e72295 100644
--- a/cc/resources/tile_manager.cc
+++ b/cc/resources/tile_manager.cc
@@ -209,11 +209,13 @@ scoped_ptr<TileManager> TileManager::Create(
     base::SequencedTaskRunner* task_runner,
     ResourcePool* resource_pool,
     TileTaskRunner* tile_task_runner,
+    int compression_threshold,
     RenderingStatsInstrumentation* rendering_stats_instrumentation,
     size_t scheduled_raster_task_limit) {
-  return make_scoped_ptr(new TileManager(
-      client, task_runner, resource_pool, tile_task_runner,
-      rendering_stats_instrumentation, scheduled_raster_task_limit));
+  return make_scoped_ptr(
+      new TileManager(client, task_runner, resource_pool, tile_task_runner,
+                      compression_threshold, rendering_stats_instrumentation,
+                      scheduled_raster_task_limit));
 }
 
 TileManager::TileManager(
@@ -221,6 +223,7 @@ TileManager::TileManager(
     const scoped_refptr<base::SequencedTaskRunner>& task_runner,
     ResourcePool* resource_pool,
     TileTaskRunner* tile_task_runner,
+    int compression_threshold,
     RenderingStatsInstrumentation* rendering_stats_instrumentation,
     size_t scheduled_raster_task_limit)
     : client_(client),
@@ -232,6 +235,7 @@ TileManager::TileManager(
       rendering_stats_instrumentation_(rendering_stats_instrumentation),
       did_check_for_completed_tasks_since_last_schedule_tasks_(true),
       did_oom_on_last_assign_(false),
+      compression_threshold_(compression_threshold),
       ready_to_activate_check_notifier_(
           task_runner_.get(),
           base::Bind(&TileManager::CheckIfReadyToActivate,
@@ -591,7 +595,8 @@ void TileManager::AssignGpuMemoryToTiles(
     MemoryUsage memory_required_by_tile_to_be_scheduled;
     if (!mts.raster_task.get()) {
       memory_required_by_tile_to_be_scheduled = MemoryUsage::FromConfig(
-          tile->size(), resource_pool_->resource_format());
+          tile->size(),
+          resource_pool_->resource_format(DetermineResourceFormatUsage(tile)));
     }
 
     bool tile_is_needed_now = priority.priority_bin == TilePriority::NOW;
@@ -647,6 +652,26 @@ void TileManager::AssignGpuMemoryToTiles(
                    had_enough_memory_to_schedule_tiles_needed_now);
 }
 
+ResourceFormatUsage TileManager::DetermineResourceFormatUsage(
+    const Tile* tile) const {
+  ResourceFormatUsage usage;
+  if (tile->size().width() % 4 != 0 || tile->size().height() % 4 != 0 ||
+      tile->frequently_invalidated()) {
+    usage = FORMAT_USAGE_NATIVE;
+  } else {
+    usage = tile->IsOpaque() ? FORMAT_USAGE_OPAQUE : FORMAT_USAGE_TRANSLUCENT;
+    // Urgent tiles can be generated faster if we avoid memory optimized
+    // formats.
+    if (compression_threshold_ >= 0) {
+      TilePriority::PriorityBin bin = tile->combined_priority().priority_bin;
+      if (static_cast<int>(bin) < compression_threshold_) {
+        usage = FORMAT_USAGE_NATIVE;
+      }
+    }
+  }
+  return usage;
+}
+
 void TileManager::FreeResourcesForTile(Tile* tile) {
   ManagedTileState& mts = tile->managed_state();
   if (mts.draw_info.resource_)
@@ -729,8 +754,8 @@ scoped_refptr<ImageDecodeTask> TileManager::CreateImageDecodeTask(
 scoped_refptr<RasterTask> TileManager::CreateRasterTask(Tile* tile) {
   ManagedTileState& mts = tile->managed_state();
 
-  scoped_ptr<ScopedResource> resource =
-      resource_pool_->AcquireResource(tile->size());
+  scoped_ptr<ScopedResource> resource = resource_pool_->AcquireResource(
+      tile->size(), DetermineResourceFormatUsage(tile));
   const ScopedResource* const_resource = resource.get();
 
   // Create and queue all image decode tasks that this tile depends on.