cc/layers/contents_scaling_layer.cc

   1 // Copyright 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cc/layers/contents_scaling_layer.h"
   6 #include "ui/gfx/geometry/size_conversions.h"
   7
   8 namespace cc {
   9
  10 gfx::Size ContentsScalingLayer::ComputeContentBoundsForScale(
  11     float scale_x,
  12     float scale_y) const {
  13   return gfx::ToCeiledSize(gfx::ScaleSize(bounds(), scale_x, scale_y));
  14 }
  15
  16 ContentsScalingLayer::ContentsScalingLayer()
  17     : last_update_contents_scale_x_(0.f),
  18       last_update_contents_scale_y_(0.f) {}
  19
  20 ContentsScalingLayer::~ContentsScalingLayer() {
  21 }
  22
  23 void ContentsScalingLayer::CalculateContentsScale(
  24     float ideal_contents_scale,
  25     float* contents_scale_x,
  26     float* contents_scale_y,
  27     gfx::Size* content_bounds) {
  28   *contents_scale_x = ideal_contents_scale;
  29   *contents_scale_y = ideal_contents_scale;
  30   *content_bounds = ComputeContentBoundsForScale(
  31       ideal_contents_scale,
  32       ideal_contents_scale);
  33 }
  34
  35 bool ContentsScalingLayer::Update(ResourceUpdateQueue* queue,
  36                                   const OcclusionTracker<Layer>* occlusion) {
  37   bool updated = Layer::Update(queue, occlusion);
  38
  39   if (draw_properties().contents_scale_x == last_update_contents_scale_x_ &&
  40       draw_properties().contents_scale_y == last_update_contents_scale_y_)
  41     return updated;
  42
  43   last_update_contents_scale_x_ = draw_properties().contents_scale_x;
  44   last_update_contents_scale_y_ = draw_properties().contents_scale_y;
  45   // Invalidate the whole layer if scale changed.
  46   SetNeedsDisplayRect(gfx::Rect(paint_properties().bounds));
  47   return updated;
  48 }
  49
  50 }  // namespace cc