src/third_party/WebKit/Source/core/rendering/RenderLayerModelObject.cpp

   1 /*
   2  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
   3  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
   4  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
   5  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
   6  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
   7  * Copyright (C) 2010, 2012 Google Inc. All rights reserved.
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Library General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Library General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Library General Public License
  20  * along with this library; see the file COPYING.LIB.  If not, write to
  21  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  22  * Boston, MA 02110-1301, USA.
  23  */
  24
  25 #include "config.h"
  26 #include "core/rendering/RenderLayerModelObject.h"
  27
  28 #include "core/frame/LocalFrame.h"
  29 #include "core/rendering/RenderLayer.h"
  30 #include "core/rendering/RenderView.h"
  31 #include "core/rendering/compositing/CompositedLayerMapping.h"
  32
  33 namespace blink {
  34
  35 bool RenderLayerModelObject::s_wasFloating = false;
  36
  37 RenderLayerModelObject::RenderLayerModelObject(ContainerNode* node)
  38     : RenderObject(node)
  39 {
  40 }
  41
  42 RenderLayerModelObject::~RenderLayerModelObject()
  43 {
  44     // Our layer should have been destroyed and cleared by now
  45     ASSERT(!hasLayer());
  46     ASSERT(!m_layer);
  47 }
  48
  49 void RenderLayerModelObject::destroyLayer()
  50 {
  51     setHasLayer(false);
  52     m_layer = nullptr;
  53 }
  54
  55 void RenderLayerModelObject::createLayer(LayerType type)
  56 {
  57     ASSERT(!m_layer);
  58     m_layer = adoptPtr(new RenderLayer(this, type));
  59     setHasLayer(true);
  60     m_layer->insertOnlyThisLayer();
  61 }
  62
  63 bool RenderLayerModelObject::hasSelfPaintingLayer() const
  64 {
  65     return m_layer && m_layer->isSelfPaintingLayer();
  66 }
  67
  68 ScrollableArea* RenderLayerModelObject::scrollableArea() const
  69 {
  70     return m_layer ? m_layer->scrollableArea() : 0;
  71 }
  72
  73 void RenderLayerModelObject::willBeDestroyed()
  74 {
  75     if (isPositioned()) {
  76         // Don't use this->view() because the document's renderView has been set to 0 during destruction.
  77         if (LocalFrame* frame = this->frame()) {
  78             if (FrameView* frameView = frame->view()) {
  79                 if (style()->hasViewportConstrainedPosition())
  80                     frameView->removeViewportConstrainedObject(this);
  81             }
  82         }
  83     }
  84
  85     RenderObject::willBeDestroyed();
  86
  87     destroyLayer();
  88 }
  89
  90 void RenderLayerModelObject::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
  91 {
  92     s_wasFloating = isFloating();
  93
  94     if (RenderStyle* oldStyle = style()) {
  95         if (parent() && diff.needsPaintInvalidationLayer()) {
  96             if (oldStyle->hasAutoClip() != newStyle.hasAutoClip()
  97                 || oldStyle->clip() != newStyle.clip())
  98                 layer()->clipper().clearClipRectsIncludingDescendants();
  99         }
 100     }
 101
 102     RenderObject::styleWillChange(diff, newStyle);
 103 }
 104
 105 void RenderLayerModelObject::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
 106 {
 107     bool hadTransform = hasTransform();
 108     bool hadLayer = hasLayer();
 109     bool layerWasSelfPainting = hadLayer && layer()->isSelfPaintingLayer();
 110
 111     RenderObject::styleDidChange(diff, oldStyle);
 112     updateFromStyle();
 113
 114     LayerType type = layerTypeRequired();
 115     if (type != NoLayer) {
 116         if (!layer() && layerCreationAllowedForSubtree()) {
 117             if (s_wasFloating && isFloating())
 118                 setChildNeedsLayout();
 119             createLayer(type);
 120             if (parent() && !needsLayout()) {
 121                 // FIXME: We should call a specialized version of this function.
 122                 layer()->updateLayerPositionsAfterLayout();
 123             }
 124         }
 125     } else if (layer() && layer()->parent()) {
 126         setHasTransform(false); // Either a transform wasn't specified or the object doesn't support transforms, so just null out the bit.
 127         setHasReflection(false);
 128         layer()->removeOnlyThisLayer(); // calls destroyLayer() which clears m_layer
 129         if (s_wasFloating && isFloating())
 130             setChildNeedsLayout();
 131         if (hadTransform)
 132             setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation();
 133     }
 134
 135     if (layer()) {
 136         // FIXME: Ideally we shouldn't need this setter but we can't easily infer an overflow-only layer
 137         // from the style.
 138         layer()->setLayerType(type);
 139
 140         layer()->styleChanged(diff, oldStyle);
 141         if (hadLayer && layer()->isSelfPaintingLayer() != layerWasSelfPainting)
 142             setChildNeedsLayout();
 143     }
 144
 145     if (FrameView *frameView = view()->frameView()) {
 146         bool newStyleIsViewportConstained = style()->hasViewportConstrainedPosition();
 147         bool oldStyleIsViewportConstrained = oldStyle && oldStyle->hasViewportConstrainedPosition();
 148         if (newStyleIsViewportConstained != oldStyleIsViewportConstrained) {
 149             if (newStyleIsViewportConstained && layer())
 150                 frameView->addViewportConstrainedObject(this);
 151             else
 152                 frameView->removeViewportConstrainedObject(this);
 153         }
 154     }
 155 }
 156
 157 void RenderLayerModelObject::addLayerHitTestRects(LayerHitTestRects& rects, const RenderLayer* currentLayer, const LayoutPoint& layerOffset, const LayoutRect& containerRect) const
 158 {
 159     if (hasLayer()) {
 160         if (isRenderView()) {
 161             // RenderView is handled with a special fast-path, but it needs to know the current layer.
 162             RenderObject::addLayerHitTestRects(rects, layer(), LayoutPoint(), LayoutRect());
 163         } else {
 164             // Since a RenderObject never lives outside it's container RenderLayer, we can switch
 165             // to marking entire layers instead. This may sometimes mark more than necessary (when
 166             // a layer is made of disjoint objects) but in practice is a significant performance
 167             // savings.
 168             layer()->addLayerHitTestRects(rects);
 169         }
 170     } else {
 171         RenderObject::addLayerHitTestRects(rects, currentLayer, layerOffset, containerRect);
 172     }
 173 }
 174
 175 void RenderLayerModelObject::invalidateTreeIfNeeded(const PaintInvalidationState& paintInvalidationState)
 176 {
 177     ASSERT(!needsLayout());
 178
 179     if (!shouldCheckForPaintInvalidation(paintInvalidationState))
 180         return;
 181
 182     bool establishesNewPaintInvalidationContainer = isPaintInvalidationContainer();
 183     const RenderLayerModelObject& newPaintInvalidationContainer = *adjustCompositedContainerForSpecialAncestors(establishesNewPaintInvalidationContainer ? this : &paintInvalidationState.paintInvalidationContainer());
 184     ASSERT(&newPaintInvalidationContainer == containerForPaintInvalidation());
 185
 186     InvalidationReason reason = invalidatePaintIfNeeded(paintInvalidationState, newPaintInvalidationContainer);
 187     clearPaintInvalidationState(paintInvalidationState);
 188
 189     PaintInvalidationState childTreeWalkState(paintInvalidationState, *this, newPaintInvalidationContainer);
 190     if (reason == InvalidationLocationChange || reason == InvalidationFull)
 191         childTreeWalkState.setForceCheckForPaintInvalidation();
 192     invalidatePaintOfSubtreesIfNeeded(childTreeWalkState);
 193 }
 194
 195 void RenderLayerModelObject::setBackingNeedsPaintInvalidationInRect(const LayoutRect& r) const
 196 {
 197     // https://bugs.webkit.org/show_bug.cgi?id=61159 describes an unreproducible crash here,
 198     // so assert but check that the layer is composited.
 199     ASSERT(compositingState() != NotComposited);
 200
 201     WebInvalidationDebugAnnotations annotations = WebInvalidationDebugAnnotationsNone;
 202     if (!hadPaintInvalidation())
 203         annotations = WebInvalidationDebugAnnotationsFirstPaint;
 204     // FIXME: The callers assume they are calling a const function but this function has a side effect.
 205     const_cast<RenderLayerModelObject*>(this)->setHadPaintInvalidation();
 206
 207     // FIXME: generalize accessors to backing GraphicsLayers so that this code is squashing-agnostic.
 208     if (layer()->groupedMapping()) {
 209         LayoutRect paintInvalidationRect = r;
 210         paintInvalidationRect.move(layer()->subpixelAccumulation());
 211         if (GraphicsLayer* squashingLayer = layer()->groupedMapping()->squashingLayer())
 212             squashingLayer->setNeedsDisplayInRect(pixelSnappedIntRect(paintInvalidationRect), annotations);
 213     } else {
 214         layer()->compositedLayerMapping()->setContentsNeedDisplayInRect(r, annotations);
 215     }
 216 }
 217
 218 } // namespace blink
 219