cc: Move tiling management out of draw properties calculation.

cc/layers/picture_image_layer_impl.cc

 // Copyright 2013 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/layers/picture_image_layer_impl.h"
 
 #include <algorithm>
 
 #include "cc/debug/debug_colors.h"
 #include "cc/trees/layer_tree_impl.h"
 
 namespace cc {
 
 PictureImageLayerImpl::PictureImageLayerImpl(LayerTreeImpl* tree_impl, int id)
     : PictureLayerImpl(tree_impl, id) {
 }
 
 PictureImageLayerImpl::~PictureImageLayerImpl() {
 }
 
 const char* PictureImageLayerImpl::LayerTypeAsString() const {
   return "cc::PictureImageLayerImpl";
 }
 
 scoped_ptr<LayerImpl> PictureImageLayerImpl::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return PictureImageLayerImpl::Create(tree_impl, id()).PassAs<LayerImpl>();
 }
 
-void PictureImageLayerImpl::CalculateContentsScale(
-    float ideal_contents_scale,
-    float device_scale_factor,
-    float page_scale_factor,
-    float maximum_animation_contents_scale,
-    bool animating_transform_to_screen,
-    float* contents_scale_x,
-    float* contents_scale_y,
-    gfx::Size* content_bounds) {
-  // CalculateRasterContentsScale always returns 1.f, so make that the ideal
-  // scale.
-  ideal_contents_scale = 1.f;
-  PictureLayerImpl::CalculateContentsScale(ideal_contents_scale,
-                                           device_scale_factor,
-                                           page_scale_factor,
-                                           maximum_animation_contents_scale,
-                                           animating_transform_to_screen,
-                                           contents_scale_x,
-                                           contents_scale_y,
-                                           content_bounds);
-}
-
 void PictureImageLayerImpl::GetDebugBorderProperties(
     SkColor* color, float* width) const {
   *color = DebugColors::ImageLayerBorderColor();
   *width = DebugColors::ImageLayerBorderWidth(layer_tree_impl());
 }
 
 bool PictureImageLayerImpl::ShouldAdjustRasterScale(
     bool animating_transform_to_screen) const {
   return false;
 }
 
 void PictureImageLayerImpl::RecalculateRasterScales(
     bool animating_transform_to_screen,
     float maximum_animation_contents_scale) {
   // Defaults from PictureLayerImpl.
   PictureLayerImpl::RecalculateRasterScales(animating_transform_to_screen,
                                             maximum_animation_contents_scale);
 
   // Don't scale images during rastering to ensure image quality, save memory
   // and avoid frequent re-rastering on change of scale.
   raster_contents_scale_ = std::max(1.f, MinimumContentsScale());
   // We don't need low res tiles.
   low_res_raster_contents_scale_ = raster_contents_scale_;
 }
 
+void PictureImageLayerImpl::UpdateIdealScales() {
+  draw_properties().ideal_contents_scale = 1.f;

[enne (OOO), 2014/05/21 18:08:44]

In general cc tries not to update draw properties outside of
UpdateDrawProperties.  Can you do this differently? Maybe just set all the
ideal_foo_scale_ variables directly here?

Can you add a unit test that PictureImageLayerImpl always generates a
PictureLayerTiling with a scale of 1 regardless of what the page/device/contents
scales are? Such a test would have caught this regression.

+  // Defaults from PictureLayerImpl.
+  PictureLayerImpl::UpdateIdealScales();
+}
+
 }  // namespace cc