cc: GPU rasterize tiles synchronously in PrepareToDraw.

cc/resources/gpu_rasterizer.cc

Index: cc/resources/gpu_rasterizer.cc
diff --git a/cc/resources/gpu_rasterizer.cc b/cc/resources/gpu_rasterizer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b8dda89807cc4bdc74f9beb7f3bca421cb494c6f
--- /dev/null
+++ b/cc/resources/gpu_rasterizer.cc
@@ -0,0 +1,146 @@
+// Copyright 2014 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/gpu_rasterizer.h"
+
+#include <algorithm>
+
+#include "base/bind.h"
+#include "base/debug/trace_event.h"
+#include "base/metrics/histogram.h"
+#include "cc/debug/devtools_instrumentation.h"
+#include "cc/debug/frame_viewer_instrumentation.h"
+#include "cc/output/context_provider.h"
+#include "cc/resources/raster_buffer.h"
+#include "cc/resources/raster_source.h"
+#include "cc/resources/resource.h"
+#include "cc/resources/resource_provider.h"
+#include "cc/resources/scoped_gpu_raster.h"
+#include "cc/resources/tile_manager.h"
+#include "gpu/command_buffer/client/gles2_interface.h"
+#include "third_party/skia/include/core/SkMultiPictureDraw.h"
+#include "third_party/skia/include/core/SkPictureRecorder.h"
+#include "third_party/skia/include/core/SkSurface.h"
+#include "third_party/skia/include/gpu/GrContext.h"
+
+namespace cc {
+namespace {
+
+// Flag to indicate whether we should try and detect that
+// a tile is of solid color.
+const bool kUseColorEstimator = true;

[vmpstr, 2014/12/23 09:51:02]

I know we have this elsewhere, but can you remove this as part of this change.
Since we control this in PLI now, I don't see a reason for having another
constant.

[hendrikw, 2014/12/23 18:10:33]

Sure, do you want me to remove the one in tilemanager too?

+
+}  // namespace
+
+// static
+scoped_ptr<GpuRasterizer> GpuRasterizer::Create(
+    ContextProvider* context_provider,
+    ResourceProvider* resource_provider,
+    bool use_distance_field_text,
+    bool tile_prepare_enabled) {
+  return make_scoped_ptr<GpuRasterizer>(
+      new GpuRasterizer(context_provider, resource_provider,
+                        use_distance_field_text, tile_prepare_enabled));
+}
+
+GpuRasterizer::GpuRasterizer(ContextProvider* context_provider,
+                             ResourceProvider* resource_provider,
+                             bool use_distance_field_text,
+                             bool tile_prepare_enabled)
+    : context_provider_(context_provider),
+      resource_provider_(resource_provider),
+      use_distance_field_text_(use_distance_field_text),
+      tile_prepare_enabled_(tile_prepare_enabled) {
+  DCHECK(context_provider_);
+}
+
+GpuRasterizer::~GpuRasterizer() {
+}
+
+PrepareTilesMode GpuRasterizer::GetPrepareTilesMode() {
+  return tile_prepare_enabled_ ? PrepareTilesMode::PREPARE_PRIORITIZED_TILES

[vmpstr, 2014/12/23 09:51:02]

It feels a bit awkward to pass this bool, since we will always have it as false
(or true after vmiura's patch). Is there some reason why it's a run time check?

[hendrikw, 2014/12/23 18:10:33]

I don't know what the plans for this are, I thought both modes would be used.
Victor, can you jump in?

[vmiura, 2014/12/23 18:33:13]

In my patch it's turned on by a "--enable-tile-prepare" flag.  We might want to
keep it behind a flag initially, so we can default on and have an option to turn
it off if anything blows up in wide release.

+                               : PrepareTilesMode::PREPARE_NONE;
+}
+
+void GpuRasterizer::RasterizeTiles(const TileVector& tiles,
+                                   ResourcePool* resource_pool,
+                                   TileManager* tile_manager) {

[vmpstr, 2014/12/23 09:51:02]

:\ I'm not really a fan of rasterizer being owned by tile manager, and it having
a reference back to it. It almost feels like a callback would be better

[hendrikw, 2014/12/23 18:10:33]

Not a fan?  We do this _EVERYWHERE_!  :)

Sure, I'll change this to a callback, though I don't think it improves things
much (sometimes too much abstraction makes it more difficult to understand).

+  ScopedGpuRaster gpu_raster(context_provider_);
+
+  for (auto tile : tiles) {
+    scoped_ptr<ScopedResource> resource =
+        resource_pool->AcquireResource(tile->size());
+    const ScopedResource* const_resource = resource.get();
+
+    RasterSource::SolidColorAnalysis analysis;
+
+    if (tile->use_picture_analysis())
+      Analyze(tile, &analysis);
+
+    if (!analysis.is_solid_color)
+      Raster(tile, const_resource);

[vmpstr, 2014/12/23 09:51:02]

Should this be called something like "AppendToMultiPictureDraw"?

[hendrikw, 2014/12/23 18:10:33]

Yes!

I'll also rename Analyze to PerformSolidColorAnalysis

+
+    tile_manager->CompleteRasterTask(tile->id(), resource.Pass(), analysis);
+  }
+
+  multi_picture_draw_.draw();
+}
+
+void GpuRasterizer::Analyze(const Tile* tile,
+                            RasterSource::SolidColorAnalysis* analysis) {
+  const void* tile_id = static_cast<const void*>(tile);
+  frame_viewer_instrumentation::ScopedAnalyzeTask analyze_task(
+      tile_id, tile->combined_priority().resolution,
+      tile->source_frame_number(), tile->layer_id());
+
+  DCHECK(tile->raster_source());
+
+  tile->raster_source()->PerformSolidColorAnalysis(
+      tile->content_rect(), tile->contents_scale(), analysis);
+
+  // Record the solid color prediction.
+  UMA_HISTOGRAM_BOOLEAN("Renderer4.SolidColorTilesAnalyzed",
+                        analysis->is_solid_color);
+
+  // Clear the flag if we're not using the estimator.
+  analysis->is_solid_color &= kUseColorEstimator;
+}
+
+void GpuRasterizer::Raster(const Tile* tile, const ScopedResource* resource) {
+  const void* tile_id = static_cast<const void*>(tile);
+  frame_viewer_instrumentation::ScopedRasterTask raster_task(
+      tile_id, tile->combined_priority().resolution,
+      tile->source_frame_number(), tile->layer_id());
+
+  DCHECK(tile->raster_source());
+
+  ResourceProvider::ScopedWriteLockGr lock(resource_provider_, resource->id());
+
+  // Turn on distance fields for layers that have ever animated.
+  bool use_distance_field_text =
+      use_distance_field_text_ ||
+      tile->raster_source()->ShouldAttemptToUseDistanceFieldText();
+  SkSurface* sk_surface = lock.GetSkSurface(
+      use_distance_field_text, tile->raster_source()->CanUseLCDText());
+
+  if (!sk_surface)
+    return;
+
+  SkPictureRecorder recorder;
+  gfx::Size size = resource->size();
+  const int flags = SkPictureRecorder::kComputeSaveLayerInfo_RecordFlag;
+  skia::RefPtr<SkCanvas> canvas = skia::SharePtr(
+      recorder.beginRecording(size.width(), size.height(), NULL, flags));
+
+  canvas->save();
+  tile->raster_source()->PlaybackToCanvas(canvas.get(), tile->content_rect(),
+                                          tile->contents_scale());
+  canvas->restore();
+
+  // Add the canvas and recorded picture to |multi_picture_draw_|.
+  skia::RefPtr<SkPicture> picture = skia::AdoptRef(recorder.endRecording());
+  multi_picture_draw_.add(sk_surface->getCanvas(), picture.get());
+}
+
+}  // namespace cc