cc/blink/web_layer_impl_fixed_bounds.cc

   1 // Copyright 2014 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/blink/web_layer_impl_fixed_bounds.h"
   6
   7 #include "cc/layers/layer.h"
   8 #include "third_party/WebKit/public/platform/WebFloatPoint.h"
   9 #include "third_party/WebKit/public/platform/WebSize.h"
  10 #include "third_party/skia/include/utils/SkMatrix44.h"
  11
  12 using cc::Layer;
  13
  14 namespace cc_blink {
  15
  16 WebLayerImplFixedBounds::WebLayerImplFixedBounds() {
  17 }
  18
  19 WebLayerImplFixedBounds::WebLayerImplFixedBounds(scoped_refptr<Layer> layer)
  20     : WebLayerImpl(layer) {
  21 }
  22
  23 WebLayerImplFixedBounds::~WebLayerImplFixedBounds() {
  24 }
  25
  26 void WebLayerImplFixedBounds::invalidateRect(const blink::WebRect& rect) {
  27   // Partial invalidations seldom occur for such layers.
  28   // Simply invalidate the whole layer to avoid transformation of coordinates.
  29   invalidate();
  30 }
  31
  32 void WebLayerImplFixedBounds::setTransformOrigin(
  33     const blink::WebFloatPoint3D& transform_origin) {
  34   if (transform_origin != this->transformOrigin()) {
  35     layer_->SetTransformOrigin(transform_origin);
  36     UpdateLayerBoundsAndTransform();
  37   }
  38 }
  39
  40 void WebLayerImplFixedBounds::setBounds(const blink::WebSize& bounds) {
  41   if (original_bounds_ != gfx::Size(bounds)) {
  42     original_bounds_ = bounds;
  43     UpdateLayerBoundsAndTransform();
  44   }
  45 }
  46
  47 blink::WebSize WebLayerImplFixedBounds::bounds() const {
  48   return original_bounds_;
  49 }
  50
  51 void WebLayerImplFixedBounds::setTransform(const SkMatrix44& matrix) {
  52   gfx::Transform transform;
  53   transform.matrix() = matrix;
  54   SetTransformInternal(transform);
  55 }
  56
  57 SkMatrix44 WebLayerImplFixedBounds::transform() const {
  58   return original_transform_.matrix();
  59 }
  60
  61 void WebLayerImplFixedBounds::SetFixedBounds(gfx::Size fixed_bounds) {
  62   if (fixed_bounds_ != fixed_bounds) {
  63     fixed_bounds_ = fixed_bounds;
  64     UpdateLayerBoundsAndTransform();
  65   }
  66 }
  67
  68 void WebLayerImplFixedBounds::SetTransformInternal(
  69     const gfx::Transform& transform) {
  70   if (original_transform_ != transform) {
  71     original_transform_ = transform;
  72     UpdateLayerBoundsAndTransform();
  73   }
  74 }
  75
  76 void WebLayerImplFixedBounds::UpdateLayerBoundsAndTransform() {
  77   if (fixed_bounds_.IsEmpty() || original_bounds_.IsEmpty() ||
  78       fixed_bounds_ == original_bounds_ ||
  79       // For now fall back to non-fixed bounds for non-zero transform origin.
  80       // TODO(wangxianzhu): Support non-zero anchor point for fixed bounds.
  81       transformOrigin().x ||
  82       transformOrigin().y) {
  83     layer_->SetBounds(original_bounds_);
  84     layer_->SetTransform(original_transform_);
  85     return;
  86   }
  87
  88   layer_->SetBounds(fixed_bounds_);
  89
  90   // Apply bounds scale (bounds/fixed_bounds) over original transform.
  91   gfx::Transform transform_with_bounds_scale(original_transform_);
  92   float bounds_scale_x =
  93       static_cast<float>(original_bounds_.width()) / fixed_bounds_.width();
  94   float bounds_scale_y =
  95       static_cast<float>(original_bounds_.height()) / fixed_bounds_.height();
  96   transform_with_bounds_scale.Scale(bounds_scale_x, bounds_scale_y);
  97   layer_->SetTransform(transform_with_bounds_scale);
  98 }
  99
 100 }  // namespace cc_blink