cc/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/picture_image_layer.h"
   6
   7 #include "third_party/skia/include/core/SkCanvas.h"
   8
   9 namespace cc {
  10
  11 scoped_refptr<PictureImageLayer> PictureImageLayer::create()
  12 {
  13   return make_scoped_refptr(new PictureImageLayer());
  14 }
  15
  16 PictureImageLayer::PictureImageLayer()
  17     : PictureLayer(this)
  18 {
  19 }
  20
  21 PictureImageLayer::~PictureImageLayer()
  22 {
  23   clearClient();
  24 }
  25
  26 void PictureImageLayer::setBitmap(const SkBitmap& bitmap)
  27 {
  28   // setBitmap() currently gets called whenever there is any
  29   // style change that affects the layer even if that change doesn't
  30   // affect the actual contents of the image (e.g. a CSS animation).
  31   // With this check in place we avoid unecessary texture uploads.
  32   if (bitmap.pixelRef() && bitmap.pixelRef() == bitmap_.pixelRef())
  33       return;
  34
  35   bitmap_ = bitmap;
  36   setNeedsDisplay();
  37 }
  38
  39 void PictureImageLayer::update(
  40     ResourceUpdateQueue& queue,
  41     const OcclusionTracker* tracker,
  42     RenderingStats& stats) {
  43   if (bounds() != bounds_) {
  44     // Pictures are recorded in layer space, so if the layer size changes,
  45     // then the picture needs to be re-scaled, as a directly composited image
  46     // always fills its entire layer bounds.  This could be improved by
  47     // recording pictures of images at their actual resolution somehow.
  48     bounds_ = bounds();
  49     setNeedsDisplay();
  50   }
  51   PictureLayer::update(queue, tracker, stats);
  52 }
  53
  54 void PictureImageLayer::paintContents(
  55     SkCanvas* canvas,
  56     const gfx::Rect& clip,
  57     gfx::RectF& opaque) {
  58   if (!bitmap_.width() || !bitmap_.height())
  59     return;
  60
  61   SkScalar content_to_layer_scale_x = SkFloatToScalar(
  62       static_cast<float>(bounds().width()) / bitmap_.width());
  63   SkScalar content_to_layer_scale_y = SkFloatToScalar(
  64       static_cast<float>(bounds().height()) / bitmap_.height());
  65   canvas->scale(content_to_layer_scale_x, content_to_layer_scale_y);
  66
  67   canvas->drawBitmap(bitmap_, 0, 0);
  68 }
  69
  70 }  // namespace cc