Raster PictureLayerTiling with fractional translation

cc/tiles/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/tiles/tile_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 45 matching lines @@
                  TileTask::Vector* dependencies,
                  bool supports_concurrent_execution)
       : TileTask(supports_concurrent_execution, dependencies),
         tile_manager_(tile_manager),
         tile_(tile),
         resource_(resource),
         raster_source_(std::move(raster_source)),
         content_rect_(tile->content_rect()),
         invalid_content_rect_(invalidated_rect),
         contents_scale_(tile->contents_scale()),
+        contents_translation_(tile->contents_translation()),
         playback_settings_(playback_settings),
         tile_resolution_(tile_resolution),
         layer_id_(tile->layer_id()),
         source_prepare_tiles_id_(source_prepare_tiles_id),
         tile_tracing_id_(static_cast<void*>(tile)),
         new_content_id_(tile->id()),
         source_frame_number_(tile->source_frame_number()),
         raster_buffer_(std::move(raster_buffer)) {
     DCHECK(origin_thread_checker_.CalledOnValidThread());
   }
 
   // Overridden from Task:
   void RunOnWorkerThread() override {
     TRACE_EVENT1("cc", "RasterizerTaskImpl::RunOnWorkerThread",
                  "source_prepare_tiles_id", source_prepare_tiles_id_);
 
     DCHECK(raster_source_.get());
     DCHECK(raster_buffer_);
 
     frame_viewer_instrumentation::ScopedRasterTask raster_task(
         tile_tracing_id_, tile_resolution_, source_frame_number_, layer_id_);
     ScopedRasterTaskTimer timer;
     timer.SetArea(content_rect_.size().GetArea());
 
     DCHECK(raster_source_);
 
     raster_buffer_->Playback(raster_source_.get(), content_rect_,
                              invalid_content_rect_, new_content_id_,
-                             contents_scale_, playback_settings_);
+                             contents_scale_, contents_translation_,
+                             playback_settings_);
   }
 
   // Overridden from TileTask:
   void OnTaskCompleted() override {
     DCHECK(origin_thread_checker_.CalledOnValidThread());
 
     // Here calling state().IsCanceled() is thread-safe, because this task is
     // already concluded as FINISHED or CANCELLED and no longer will be worked
     // upon by task graph runner.
     tile_manager_->OnRasterTaskCompleted(std::move(raster_buffer_), tile_,
@@ skipping 14 matching lines @@
   // origin thread. Ensure their access by checking CalledOnValidThread().
   TileManager* tile_manager_;
   Tile* tile_;
   Resource* resource_;
 
   // The following members should be used for running the task.
   scoped_refptr<RasterSource> raster_source_;
   gfx::Rect content_rect_;
   gfx::Rect invalid_content_rect_;
   float contents_scale_;
+  gfx::Vector2dF contents_translation_;
   RasterSource::PlaybackSettings playback_settings_;
   TileResolution tile_resolution_;
   int layer_id_;
   uint64_t source_prepare_tiles_id_;
   void* tile_tracing_id_;
   uint64_t new_content_id_;
   int source_frame_number_;
   std::unique_ptr<RasterBuffer> raster_buffer_;
 
   DISALLOW_COPY_AND_ASSIGN(RasterTaskImpl);
@@ skipping 495 matching lines @@
       break;
     }
 
     bool tile_is_needed_now = priority.priority_bin == TilePriority::NOW;
     if (tile->use_picture_analysis() && kUseColorEstimator) {
       // We analyze for solid color here, to decide to continue
       // or drop the tile for scheduling and raster.
       // TODO(sohanjg): Check if we could use a shared analysis
       // canvas which is reset between tiles.
       SkColor color = SK_ColorTRANSPARENT;
+      gfx::RectF layer_rect(tile->content_rect());
+      layer_rect.Offset(-tile->contents_translation());
+      layer_rect.Scale(1 / tile->contents_scale());
       bool is_solid_color =
           prioritized_tile.raster_source()->PerformSolidColorAnalysis(
-              tile->content_rect(), tile->contents_scale(), &color);
+              gfx::ToEnclosingRect(layer_rect), 1.f, &color);

[enne (OOO), 2016/07/26 00:22:16]

You should probably pass the translation through here.

[trchen, 2016/08/03 06:06:07]

IMO it is better to avoid RasterSource from knowing tiling details like contents
space. Either way is doable. What's the advantage of letting RasterSource handle
it?

       if (is_solid_color) {
         tile->draw_info().set_solid_color(color);
         tile->draw_info().set_was_ever_ready_to_draw();
         if (!tile_is_needed_now)
           tile->draw_info().set_was_a_prepaint_tile();
         client_->NotifyTileStateChanged(tile);
         continue;
       }
     }
 
@@ skipping 676 matching lines @@
   all_tile_tasks_completed = false;
   did_notify_all_tile_tasks_completed = false;
 }
 
 TileManager::PrioritizedWorkToSchedule::PrioritizedWorkToSchedule() = default;
 TileManager::PrioritizedWorkToSchedule::PrioritizedWorkToSchedule(
     PrioritizedWorkToSchedule&& other) = default;
 TileManager::PrioritizedWorkToSchedule::~PrioritizedWorkToSchedule() = default;
 
 }  // namespace cc