cc/layers/picture_image_layer.cc

   1 // Copyright 2010 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/picture_image_layer.h"
   6
   7 #include "cc/layers/picture_image_layer_impl.h"
   8 #include "cc/playback/display_item_list_settings.h"
   9 #include "cc/playback/drawing_display_item.h"
  10 #include "third_party/skia/include/core/SkCanvas.h"
  11 #include "third_party/skia/include/core/SkImage.h"
  12 #include "third_party/skia/include/core/SkPictureRecorder.h"
  13 #include "ui/gfx/skia_util.h"
  14
  15 namespace cc {
  16
  17 scoped_refptr<PictureImageLayer> PictureImageLayer::Create(
  18     const LayerSettings& settings) {
  19   return make_scoped_refptr(new PictureImageLayer(settings));
  20 }
  21
  22 PictureImageLayer::PictureImageLayer(const LayerSettings& settings)
  23     : PictureLayer(settings, this) {
  24 }
  25
  26 PictureImageLayer::~PictureImageLayer() {
  27   ClearClient();
  28 }
  29
  30 scoped_ptr<LayerImpl> PictureImageLayer::CreateLayerImpl(
  31     LayerTreeImpl* tree_impl) {
  32   return PictureImageLayerImpl::Create(tree_impl, id(), is_mask());
  33 }
  34
  35 bool PictureImageLayer::HasDrawableContent() const {
  36   return image_ && PictureLayer::HasDrawableContent();
  37 }
  38
  39 void PictureImageLayer::SetImage(skia::RefPtr<const SkImage> image) {
  40   // SetImage() currently gets called whenever there is any
  41   // style change that affects the layer even if that change doesn't
  42   // affect the actual contents of the image (e.g. a CSS animation).
  43   // With this check in place we avoid unecessary texture uploads.
  44   if (image_.get() == image.get())
  45     return;
  46
  47   image_ = image.Pass();
  48   UpdateDrawsContent(HasDrawableContent());
  49   SetNeedsDisplay();
  50 }
  51
  52 void PictureImageLayer::PaintContents(
  53     SkCanvas* canvas,
  54     const gfx::Rect& clip,
  55     ContentLayerClient::PaintingControlSetting painting_control) {
  56   DCHECK(image_);
  57   DCHECK_GT(image_->width(), 0);
  58   DCHECK_GT(image_->height(), 0);
  59
  60   SkScalar content_to_layer_scale_x =
  61       SkFloatToScalar(static_cast<float>(bounds().width()) / image_->width());
  62   SkScalar content_to_layer_scale_y =
  63       SkFloatToScalar(static_cast<float>(bounds().height()) / image_->height());
  64   canvas->scale(content_to_layer_scale_x, content_to_layer_scale_y);
  65
  66   // Because Android WebView resourceless software draw mode rasters directly
  67   // to the root canvas, this draw must use the kSrcOver_Mode so that
  68   // transparent images blend correctly.
  69   canvas->drawImage(image_.get(), 0, 0);
  70 }
  71
  72 scoped_refptr<DisplayItemList> PictureImageLayer::PaintContentsToDisplayList(
  73     const gfx::Rect& clip,
  74     ContentLayerClient::PaintingControlSetting painting_control) {
  75   // Picture image layers can be used with GatherPixelRefs, so cached SkPictures
  76   // are currently required.
  77   DisplayItemListSettings settings;
  78   settings.use_cached_picture = true;
  79   scoped_refptr<DisplayItemList> display_list =
  80       DisplayItemList::Create(clip, settings);
  81
  82   SkPictureRecorder recorder;
  83   SkCanvas* canvas = recorder.beginRecording(gfx::RectToSkRect(clip));
  84   PaintContents(canvas, clip, painting_control);
  85
  86   skia::RefPtr<SkPicture> picture =
  87       skia::AdoptRef(recorder.endRecordingAsPicture());
  88   auto* item = display_list->CreateAndAppendItem<DrawingDisplayItem>();
  89   item->SetNew(picture.Pass());
  90
  91   display_list->Finalize();
  92   return display_list;
  93 }
  94
  95 bool PictureImageLayer::FillsBoundsCompletely() const {
  96   return false;
  97 }
  98
  99 size_t PictureImageLayer::GetApproximateUnsharedMemoryUsage() const {
 100   return 0;
 101 }
 102
 103 }  // namespace cc