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