cc: GPU rasterize tiles synchronously in PrepareToDraw

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/basictypes.h"
@@ skipping 310 matching lines @@
   if (pending_tree_)
     pending_tree_->ApplyScrollDeltasSinceBeginMainFrame();
   sync_tree()->set_needs_update_draw_properties();
 
   if (settings_.impl_side_painting) {
     // Impl-side painting needs an update immediately post-commit to have the
     // opportunity to create tilings.  Other paths can call UpdateDrawProperties
     // more lazily when needed prior to drawing.
     sync_tree()->UpdateDrawProperties();
     // Start working on newly created tiles immediately if needed.
-    if (tile_manager_ && tile_priorities_dirty_)
+    if (tile_manager_ && tile_priorities_dirty_ && !use_gpu_rasterization_)

[vmiura, 2014/11/20 02:27:11]

Remove check for use_gpu_rasterization_, as we check it in ManageTiles.

[vmiura, 2014/11/20 02:53:45]

I take that back, since we need to run the "else" part and activate right now.

       ManageTiles();
     else
       NotifyReadyToActivate();
   } else {
     // If we're not in impl-side painting, the tree is immediately considered
     // active.
     ActivateSyncTree();
   }
 
   micro_benchmark_controller_.DidCompleteCommit();
@@ skipping 53 matching lines @@
 
 void LayerTreeHostImpl::Animate(base::TimeTicks monotonic_time) {
   if (input_handler_client_)
     input_handler_client_->Animate(monotonic_time);
   AnimatePageScale(monotonic_time);
   AnimateLayers(monotonic_time);
   AnimateScrollbars(monotonic_time);
   AnimateTopControls(monotonic_time);
 }
 
+void LayerTreeHostImpl::RasterizeTiles() {
+  if (!tile_manager_)
+    return;
+  if (!tile_priorities_dirty_)
+    return;
+
+  tile_priorities_dirty_ = false;
+  tile_manager_->RasterizeTiles(global_tile_state_);
+}
+
 void LayerTreeHostImpl::ManageTiles() {
   if (!tile_manager_)
     return;
   if (!tile_priorities_dirty_)
     return;
+  if (use_gpu_rasterization_)
+    return;
 
   tile_priorities_dirty_ = false;
   tile_manager_->ManageTiles(global_tile_state_);
 
   client_->DidManageTiles();
 }
 
 bool LayerTreeHostImpl::IsCurrentlyScrollingLayerAt(
     const gfx::Point& viewport_point,
     InputHandler::ScrollInputType type) {
@@ skipping 617 matching lines @@
   // as part of the current frame being drawn.
   if (settings().impl_side_painting)
     tile_manager_->UpdateVisibleTiles();
 
   UMA_HISTOGRAM_CUSTOM_COUNTS(
       "Compositing.NumActiveLayers", active_tree_->NumLayers(), 1, 400, 20);
 
   bool ok = active_tree_->UpdateDrawProperties();
   DCHECK(ok) << "UpdateDrawProperties failed during draw";
 
+  if (use_gpu_rasterization_)
+    RasterizeTiles();

[brianderson, 2014/11/20 02:40:19]

Should we only RasterizeTiles if draw_result == DRAW_SUCCESS at then end?

Alternatively, does it work to call RasterizeTiles in DrawLayers after the
NoDamage early out?

[reveman, 2014/11/20 15:20:59]

How you considered rasterizing at draw time instead? It would guarantee that
we're no rasterizing any tiles that are not needed for the frame.

[vmiura, 2014/11/20 18:28:57]

I put it here in the prototype as it needs to be done after
active_tree->UpdateDrawProperties() but before CalculateRenderPasses().

[reveman, 2014/11/20 19:07:54]

Why before CalculateRenderPasses()?

+
   frame->render_surface_layer_list = &active_tree_->RenderSurfaceLayerList();
   frame->render_passes.clear();
   frame->render_passes_by_id.clear();
   frame->will_draw_layers.clear();
   frame->has_no_damage = false;
 
   if (active_tree_->root_layer()) {
     gfx::Rect device_viewport_damage_rect = viewport_damage_rect_;
     viewport_damage_rect_ = gfx::Rect();
 
@@ skipping 771 matching lines @@
 
   // If we just became visible, we have to ensure that we draw high res tiles,
   // to prevent checkerboard/low res flashes.
   if (visible_)
     SetRequiresHighResToDraw();
   else
     EvictAllUIResources();
 
   // Evict tiles immediately if invisible since this tab may never get another
   // draw or timer tick.
-  if (!visible_)
+  if (!visible_ && !use_gpu_rasterization_)

[vmiura, 2014/11/20 02:27:11]

Remove check for use_gpu_rasterization_, as we check it in ManageTiles.

     ManageTiles();
 
   if (!renderer_)
     return;
 
   renderer_->SetVisible(visible);
 }
 
 void LayerTreeHostImpl::SetNeedsAnimate() {
   NotifySwapPromiseMonitorsOfSetNeedsRedraw();
@@ skipping 1593 matching lines @@
 }
 
 void LayerTreeHostImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
   std::vector<PictureLayerImpl*>::iterator it =
       std::find(picture_layers_.begin(), picture_layers_.end(), layer);
   DCHECK(it != picture_layers_.end());
   picture_layers_.erase(it);
 }
 
 }  // namespace cc