cc: Low quality support for low res tiles

cc/resources/tile_manager.cc

 // Copyright 2012 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/resources/tile_manager.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
 #include "base/json/json_writer.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "cc/debug/devtools_instrumentation.h"
 #include "cc/debug/traced_value.h"
 #include "cc/resources/image_raster_worker_pool.h"
 #include "cc/resources/pixel_buffer_raster_worker_pool.h"
 #include "cc/resources/tile.h"
+#include "skia/ext/paint_simplifier.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "ui/gfx/rect_conversions.h"
 
 namespace cc {
 
 namespace {
 
+class DisableLCDTextFilter : public SkDrawFilter {
+ public:
+  // SkDrawFilter interface.
+  virtual bool filter(SkPaint* paint, SkDrawFilter::Type type) OVERRIDE {
+    if (type != SkDrawFilter::kText_Type)
+      return true;
+
+    paint->setLCDRenderText(false);
+    return true;
+  }
+};
+
 // Determine bin based on three categories of tiles: things we need now,
 // things we need soon, and eventually.
 inline TileManagerBin BinFromTilePriority(const TilePriority& prio) {
   // The amount of time for which we want to have prepainting coverage.
   const float kPrepaintingWindowTimeSeconds = 1.0f;
   const float kBackflingGuardDistancePixels = 314.0f;
 
   if (prio.time_to_visible_in_seconds == 0)
     return NOW_BIN;
 
@@ skipping 263 matching lines @@
 
   if (!client_->ShouldForceTileUploadsRequiredForActivationToComplete())
     return;
 
   TileSet initialized_tiles;
   for (TileSet::iterator it =
            tiles_that_need_to_be_initialized_for_activation_.begin();
        it != tiles_that_need_to_be_initialized_for_activation_.end();
        ++it) {
     Tile* tile = *it;
-    if (!tile->managed_state().raster_task.is_null() &&
-        !tile->tile_version().forced_upload_) {
-      if (!raster_worker_pool_->ForceUploadToComplete(
-              tile->managed_state().raster_task))
-        continue;
+    ManagedTileState& mts = tile->managed_state();
 
-      // Setting |forced_upload_| to true makes this tile ready to draw.

[reveman, 2013/06/05 18:01:32]

lets keep this comment. just s/this tile/this tile version/

[vmpstr, 2013/06/06 01:54:20]

Done.

-      tile->tile_version().forced_upload_ = true;
-      initialized_tiles.insert(tile);
+    for (int mode = NUM_RASTER_MODES - 1; mode >= 0; --mode) {
+      ManagedTileState::TileVersion& pending_version =
+          mts.tile_versions[mode];
+      if (!pending_version.raster_task_.is_null() &&
+          !pending_version.forced_upload_) {
+        if (!raster_worker_pool_->ForceUploadToComplete(
+                pending_version.raster_task_)) {
+          continue;
+        }
+        pending_version.forced_upload_ = true;
+        initialized_tiles.insert(tile);
+        break;
+      }
     }
   }
 
   for (TileSet::iterator it = initialized_tiles.begin();
        it != initialized_tiles.end();
        ++it) {
     Tile* tile = *it;
     DidFinishTileInitialization(tile);
     DCHECK(tile->tile_version().IsReadyToDraw());
   }
@@ skipping 58 matching lines @@
 }
 
 void TileManager::AddRequiredTileForActivation(Tile* tile) {
   DCHECK(std::find(tiles_that_need_to_be_initialized_for_activation_.begin(),
                    tiles_that_need_to_be_initialized_for_activation_.end(),
                    tile) ==
          tiles_that_need_to_be_initialized_for_activation_.end());
   tiles_that_need_to_be_initialized_for_activation_.insert(tile);
 }
 
+TileRasterMode TileManager::DetermineRasterMode(const Tile* tile) const {
+  DCHECK(tile);
+  DCHECK(tile->picture_pile());
+
+  TileRasterMode raster_mode;
+
+  if (tile->managed_state().resolution == LOW_RESOLUTION)
+    raster_mode = LOW_QUALITY_RASTER_MODE;
+  else if (!tile->picture_pile()->can_use_lcd_text())
+    raster_mode = HIGH_QUALITY_NO_LCD_RASTER_MODE;
+  else
+    raster_mode = HIGH_QUALITY_RASTER_MODE;
+
+  return raster_mode;
+}
+
 void TileManager::AssignGpuMemoryToTiles() {
   TRACE_EVENT0("cc", "TileManager::AssignGpuMemoryToTiles");
 
   // Now give memory out to the tiles until we're out, and build
   // the needs-to-be-rasterized queue.
   tiles_that_need_to_be_rasterized_.clear();
   tiles_that_need_to_be_initialized_for_activation_.clear();
 
   size_t bytes_releasable = 0;
   for (TileVector::const_iterator it = tiles_.begin();
@@ skipping 16 matching lines @@
   size_t bytes_that_exceeded_memory_budget_in_now_bin = 0;
   size_t bytes_left = bytes_allocatable;
   size_t bytes_oom_in_now_bin_on_pending_tree = 0;
   TileVector tiles_requiring_memory_but_oomed;
   bool higher_priority_tile_oomed = false;
   for (TileVector::iterator it = tiles_.begin();
        it != tiles_.end();
        ++it) {
     Tile* tile = *it;
     ManagedTileState& mts = tile->managed_state();
-    ManagedTileState::TileVersion& tile_version = tile->tile_version();
+    mts.raster_mode = DetermineRasterMode(tile);

[reveman, 2013/06/05 18:01:32]

Please DCHECK that new raster_mode is not worse than last as that would cause
unnecessary raster. 

[vmpstr, 2013/06/06 01:54:20]

Turns out that when you switch tabs, the inactive one becomes a worse raster
mode. I've added a check for that instead, so we always keep the better version
if we have it.

+    ManagedTileState::TileVersion& tile_version =
+        mts.tile_versions[mts.raster_mode];
 
     // If this tile doesn't need a resource, then nothing to do.
     if (!tile_version.requires_resource())
       continue;
 
     // If the tile is not needed, free it up.
     if (mts.is_in_never_bin_on_both_trees()) {
       FreeResourcesForTile(tile);
       continue;
     }
 
     size_t tile_bytes = 0;
 
     // It costs to maintain a resource.
-    if (tile_version.resource_)
+    for (int mode = 0; mode < NUM_RASTER_MODES; ++mode) {
+      if (mts.tile_versions[mode].resource_)
+        tile_bytes += tile->bytes_consumed_if_allocated();
+    }
+
+    // If we don't have the required version, and it's not in flight
+    // then we'll have to pay to create a new task.
+    if (!tile_version.resource_ && tile_version.raster_task_.is_null()) {
       tile_bytes += tile->bytes_consumed_if_allocated();
-
-    // It will cost to allocate a resource.
-    // Note that this is separate from the above condition,
-    // so that it's clear why we're adding memory.
-    if (!tile_version.resource_ && mts.raster_task.is_null())
-      tile_bytes += tile->bytes_consumed_if_allocated();
+    }

[reveman, 2013/06/05 18:01:32]

nit: {} not required

[vmpstr, 2013/06/06 01:54:20]

Done.

 
     // Tile is OOM.
     if (tile_bytes > bytes_left) {
       tile->tile_version().set_rasterize_on_demand();
       if (mts.tree_bin[PENDING_TREE] == NOW_BIN) {
         tiles_requiring_memory_but_oomed.push_back(tile);
         bytes_oom_in_now_bin_on_pending_tree += tile_bytes;
       }
       FreeResourcesForTile(tile);
       higher_priority_tile_oomed = true;
       continue;
     }
 
     tile_version.set_use_resource();
     bytes_left -= tile_bytes;
 
     // Tile shouldn't be rasterized if we've failed to assign
     // gpu memory to a higher priority tile. This is important for
     // two reasons:
     // 1. Tile size should not impact raster priority.
     // 2. Tile with unreleasable memory could otherwise incorrectly
     //    be added as it's not affected by |bytes_allocatable|.
     if (higher_priority_tile_oomed)
       continue;
 
     if (!tile_version.resource_)
       tiles_that_need_to_be_rasterized_.push_back(tile);
 
-    if (!tile_version.resource_ && tile->required_for_activation())
+    if (!tile_version.resource_ &&

[reveman, 2013/06/05 18:01:32]

should the "!tile_version.resource_" be here? seems like IsReadyToDraw should be
enough.

[vmpstr, 2013/06/06 01:54:20]

Done.

+        !tile->tile_version().IsReadyToDraw() &&
+        tile->required_for_activation()) {
       AddRequiredTileForActivation(tile);
+    }
   }
 
   // In OOM situation, we iterate tiles_, remove the memory for active tree
   // and not the now bin. And give them to bytes_oom_in_now_bin_on_pending_tree
   if (!tiles_requiring_memory_but_oomed.empty()) {
     size_t bytes_freed = 0;
     for (TileVector::iterator it = tiles_.begin(); it != tiles_.end(); ++it) {
       Tile* tile = *it;
       ManagedTileState& mts = tile->managed_state();
-      ManagedTileState::TileVersion& tile_version = tile->tile_version();
+      ManagedTileState::TileVersion& tile_version =
+          mts.tile_versions[mts.raster_mode];

[reveman, 2013/06/05 18:01:32]

Do you need a TileRasterMode loop here to free all resources rather than just
tile_versions[mts.raster_mode]?

[vmpstr, 2013/06/06 01:54:20]

Done.

       if (tile_version.resource_ &&
           mts.tree_bin[PENDING_TREE] == NEVER_BIN &&
           mts.tree_bin[ACTIVE_TREE] != NOW_BIN) {
         DCHECK(!tile->required_for_activation());
         FreeResourcesForTile(tile);
         tile_version.set_rasterize_on_demand();
         bytes_freed += tile->bytes_consumed_if_allocated();
         TileVector::iterator it = std::find(
                 tiles_that_need_to_be_rasterized_.begin(),
                 tiles_that_need_to_be_rasterized_.end(),
                 tile);
         if (it != tiles_that_need_to_be_rasterized_.end())
             tiles_that_need_to_be_rasterized_.erase(it);
         if (bytes_oom_in_now_bin_on_pending_tree <= bytes_freed)
           break;
       }
     }
 
     for (TileVector::iterator it = tiles_requiring_memory_but_oomed.begin();
          it != tiles_requiring_memory_but_oomed.end() && bytes_freed > 0;
          ++it) {
       Tile* tile = *it;
+      ManagedTileState& mts = tile->managed_state();
       size_t bytes_needed = tile->bytes_consumed_if_allocated();
       if (bytes_needed > bytes_freed)
         continue;
-      tile->tile_version().set_use_resource();
+      mts.tile_versions[mts.raster_mode].set_use_resource();
       bytes_freed -= bytes_needed;
       tiles_that_need_to_be_rasterized_.push_back(tile);
       if (tile->required_for_activation())
         AddRequiredTileForActivation(tile);
     }
   }
 
   ever_exceeded_memory_budget_ |=
       bytes_that_exceeded_memory_budget_in_now_bin > 0;
   if (ever_exceeded_memory_budget_) {
       TRACE_COUNTER_ID2("cc", "over_memory_budget", this,
                         "budget", global_state_.memory_limit_in_bytes,
                         "over", bytes_that_exceeded_memory_budget_in_now_bin);
   }
   memory_stats_from_last_assign_.total_budget_in_bytes =
       global_state_.memory_limit_in_bytes;
   memory_stats_from_last_assign_.bytes_allocated =
       bytes_allocatable - bytes_left;
   memory_stats_from_last_assign_.bytes_unreleasable =
       bytes_allocatable - bytes_releasable;
   memory_stats_from_last_assign_.bytes_over =
       bytes_that_exceeded_memory_budget_in_now_bin;
 }
 
 void TileManager::FreeResourcesForTile(Tile* tile) {
-  if (tile->tile_version().resource_) {
-    resource_pool_->ReleaseResource(
-        tile->tile_version().resource_.Pass());
+  ManagedTileState& mts = tile->managed_state();
+  for (int mode = 0; mode < NUM_RASTER_MODES; ++mode) {
+    if (mts.tile_versions[mode].resource_) {
+      resource_pool_->ReleaseResource(
+          mts.tile_versions[mode].resource_.Pass());
+    }
   }
 }
 
+void TileManager::FreeUnusedResourcesForTile(Tile* tile) {
+  ManagedTileState& mts = tile->managed_state();
+  ManagedTileState::TileVersion& used_tile_version = tile->tile_version();
+  for (int mode = 0; mode < NUM_RASTER_MODES; ++mode) {
+    if (&mts.tile_versions[mode] != &used_tile_version &&
+        mts.tile_versions[mode].resource_) {
+      resource_pool_->ReleaseResource(
+          mts.tile_versions[mode].resource_.Pass());
+    }
+  }
+}
+
 void TileManager::ScheduleTasks() {
   TRACE_EVENT0("cc", "TileManager::ScheduleTasks");
   RasterWorkerPool::RasterTask::Queue tasks;
 
   // Build a new task queue containing all task currently needed. Tasks
   // are added in order of priority, highest priority task first.
   for (TileVector::iterator it = tiles_that_need_to_be_rasterized_.begin();
        it != tiles_that_need_to_be_rasterized_.end();
        ++it) {
     Tile* tile = *it;
     ManagedTileState& mts = tile->managed_state();
+    ManagedTileState::TileVersion& tile_version =
+        mts.tile_versions[mts.raster_mode];
 
-    DCHECK(tile->tile_version().requires_resource());
-    DCHECK(!tile->tile_version().resource_);
+    DCHECK(tile_version.requires_resource());
 
-    // Create raster task for this tile if necessary.
-    if (mts.raster_task.is_null())
-      mts.raster_task = CreateRasterTask(tile);
+    if (tile_version.raster_task_.is_null())
+      tile_version.raster_task_ = CreateRasterTask(tile);
 
-    // Finally append raster task.
-    tasks.Append(mts.raster_task);
+    tasks.Append(tile_version.raster_task_);
   }
 
   // Schedule running of |tasks|. This replaces any previously
   // scheduled tasks and effectively cancels all tasks not present
   // in |tasks|.
   raster_worker_pool_->ScheduleTasks(&tasks);
 }
 
 RasterWorkerPool::Task TileManager::CreateImageDecodeTask(
     Tile* tile, skia::LazyPixelRef* pixel_ref) {
@@ skipping 21 matching lines @@
 TileManager::RasterTaskMetadata TileManager::GetRasterTaskMetadata(
     const Tile& tile) const {
   RasterTaskMetadata metadata;
   const ManagedTileState& mts = tile.managed_state();
   metadata.is_tile_in_pending_tree_now_bin =
       mts.tree_bin[PENDING_TREE] == NOW_BIN;
   metadata.tile_resolution = mts.resolution;
   metadata.layer_id = tile.layer_id();
   metadata.tile_id = &tile;
   metadata.source_frame_number = tile.source_frame_number();
+  metadata.raster_mode = mts.raster_mode;
   return metadata;
 }
 
 RasterWorkerPool::RasterTask TileManager::CreateRasterTask(Tile* tile) {
   TRACE_EVENT0("cc", "TileManager::CreateRasterTask");
 
   scoped_ptr<ResourcePool::Resource> resource =
       resource_pool_->AcquireResource(
           tile->tile_size_.size(),
           tile->tile_version().resource_format_);
   const Resource* const_resource = resource.get();
 
-  tile->tile_version().resource_id_ = resource->id();
+  ManagedTileState& mts = tile->managed_state();
+  mts.tile_versions[mts.raster_mode].resource_id_ = resource->id();
 
   PicturePileImpl::Analysis* analysis = new PicturePileImpl::Analysis;
 
   // Create and queue all image decode tasks that this tile depends on.
   RasterWorkerPool::Task::Set decode_tasks;
   for (PicturePileImpl::PixelRefIterator iter(tile->content_rect(),
                                               tile->contents_scale(),
                                               tile->picture_pile());
        iter; ++iter) {
     skia::LazyPixelRef* pixel_ref = *iter;
@@ skipping 12 matching lines @@
       continue;
     }
 
     // Create and append new image decode task for this pixel ref.
     RasterWorkerPool::Task decode_task = CreateImageDecodeTask(
         tile, pixel_ref);
     decode_tasks.Insert(decode_task);
     pending_decode_tasks_[id] = decode_task;
   }
 
+  RasterTaskMetadata metadata = GetRasterTaskMetadata(*tile);
   return RasterWorkerPool::RasterTask(
       tile->picture_pile(),
       const_resource,
       base::Bind(&TileManager::RunAnalyzeAndRasterTask,
                  base::Bind(&TileManager::RunAnalyzeTask,
                             analysis,
                             tile->content_rect(),
                             tile->contents_scale(),
                             use_color_estimator_,
-                            GetRasterTaskMetadata(*tile),
+                            metadata,
                             rendering_stats_instrumentation_),
                  base::Bind(&TileManager::RunRasterTask,
                             analysis,
                             tile->content_rect(),
                             tile->contents_scale(),
-                            GetRasterTaskMetadata(*tile),
+                            metadata,
                             rendering_stats_instrumentation_)),
       base::Bind(&TileManager::OnRasterTaskCompleted,
                  base::Unretained(this),
                  make_scoped_refptr(tile),
                  base::Passed(&resource),
-                 base::Owned(analysis)),
+                 base::Owned(analysis),
+                 metadata.raster_mode),
       &decode_tasks);
 }
 
 void TileManager::OnRasterTaskCompleted(
     scoped_refptr<Tile> tile,
     scoped_ptr<ResourcePool::Resource> resource,
     PicturePileImpl::Analysis* analysis,
+    TileRasterMode raster_mode,
     bool was_canceled) {
   TRACE_EVENT1("cc", "TileManager::OnRasterTaskCompleted",
                "was_canceled", was_canceled);
 
   ManagedTileState& mts = tile->managed_state();
-  DCHECK(!mts.raster_task.is_null());

[reveman, 2013/06/05 18:01:32]

please keep this DCHECK.

[vmpstr, 2013/06/06 01:54:20]

Done.

-  mts.raster_task.Reset();
+  ManagedTileState::TileVersion& tile_version =
+      mts.tile_versions[raster_mode];
+  tile_version.raster_task_.Reset();
+  tile_version.resource_ = resource.Pass();

[reveman, 2013/06/05 18:01:32]

can you do this below the was_canceled check as before? I think it's cleaner to
not temporarily set resource_ when canceled or solid.

[vmpstr, 2013/06/06 01:54:20]

Done.

+  tile_version.forced_upload_ = false;

[reveman, 2013/06/05 18:01:32]

this is new. do we need it?

[vmpstr, 2013/06/06 01:54:20]

I don't really see where the flag is reset back in here... If anything, this
just makes sure that the state is consistent since we know that at that point
the resource isn't forced. Right?

[reveman, 2013/06/06 06:02:02]

Good call. This might be causing some of the rendering issues we're currently
seeing so I moved it to a separate patch that I'd like to land first.

 
   if (was_canceled) {
-    resource_pool_->ReleaseResource(resource.Pass());
+    resource_pool_->ReleaseResource(tile_version.resource_.Pass());
     return;
   }
 
   mts.picture_pile_analysis = *analysis;
   mts.picture_pile_analyzed = true;
 
   if (analysis->is_solid_color) {
-    tile->tile_version().set_solid_color(analysis->solid_color);
-    resource_pool_->ReleaseResource(resource.Pass());
-  } else {
-    tile->tile_version().resource_ = resource.Pass();
+    resource_pool_->ReleaseResource(tile_version.resource_.Pass());
+    tile_version.set_solid_color(analysis->solid_color);
   }
 
+  FreeUnusedResourcesForTile(tile.get());
+
   DidFinishTileInitialization(tile.get());
 }
 
 void TileManager::DidFinishTileInitialization(Tile* tile) {
   if (tile->priority(ACTIVE_TREE).distance_to_visible_in_pixels == 0)
     did_initialize_visible_tile_ = true;
   if (tile->required_for_activation()) {
     // It's possible that a tile required for activation is not in this list
     // if it was marked as being required after being dispatched for
     // rasterization but before AssignGPUMemory was called again.
@@ skipping 63 matching lines @@
   analysis->is_solid_color &= use_color_estimator;
 }
 
 scoped_ptr<base::Value> TileManager::RasterTaskMetadata::AsValue() const {
   scoped_ptr<base::DictionaryValue> res(new base::DictionaryValue());
   res->Set("tile_id", TracedValue::CreateIDRef(tile_id).release());
   res->SetBoolean("is_tile_in_pending_tree_now_bin",
                   is_tile_in_pending_tree_now_bin);
   res->Set("resolution", TileResolutionAsValue(tile_resolution).release());
   res->SetInteger("source_frame_number", source_frame_number);
+  res->SetInteger("raster_mode", raster_mode);
   return res.PassAs<base::Value>();
 }
 
 // static
 bool TileManager::RunRasterTask(
     PicturePileImpl::Analysis* analysis,
     gfx::Rect rect,
     float contents_scale,
     const RasterTaskMetadata& metadata,
     RenderingStatsInstrumentation* stats_instrumentation,
     SkDevice* device,
     PicturePileImpl* picture_pile) {
   TRACE_EVENT1(
       "cc", "TileManager::RunRasterTask",
       "metadata", TracedValue::FromValue(metadata.AsValue().release()));
   devtools_instrumentation::ScopedLayerTask raster_task(
       devtools_instrumentation::kRasterTask, metadata.layer_id);
 
   DCHECK(picture_pile);
   DCHECK(analysis);
   DCHECK(device);
 
   if (analysis->is_solid_color)
     return false;
 
   SkCanvas canvas(device);
 
+  skia::RefPtr<SkDrawFilter> draw_filter;
+  switch (metadata.raster_mode) {
+    case LOW_QUALITY_RASTER_MODE:
+      draw_filter = skia::AdoptRef(new skia::PaintSimplifier);
+      break;
+    case HIGH_QUALITY_NO_LCD_RASTER_MODE:
+      draw_filter = skia::AdoptRef(new DisableLCDTextFilter);
+      break;
+    case HIGH_QUALITY_RASTER_MODE:
+      break;
+    case NUM_RASTER_MODES:
+    default:
+      NOTREACHED();
+  }
+
+  canvas.setDrawFilter(draw_filter.get());
+
   if (stats_instrumentation->record_rendering_stats()) {
     PicturePileImpl::RasterStats raster_stats;
     picture_pile->RasterToBitmap(&canvas, rect, contents_scale, &raster_stats);
     stats_instrumentation->AddRaster(
         raster_stats.total_rasterize_time,
         raster_stats.best_rasterize_time,
         raster_stats.total_pixels_rasterized,
         metadata.is_tile_in_pending_tree_now_bin);
 
     HISTOGRAM_CUSTOM_COUNTS(
         "Renderer4.PictureRasterTimeUS",
         raster_stats.total_rasterize_time.InMicroseconds(),
         0,
         100000,
         100);
   } else {
     picture_pile->RasterToBitmap(&canvas, rect, contents_scale, NULL);
   }
 
   return true;
 }
 
 }  // namespace cc