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
  32 namespace blink {
  33
  34 bool RenderLayerModelObject::s_wasFloating = false;
  35
  36 RenderLayerModelObject::RenderLayerModelObject(ContainerNode* node)
  37     : RenderObject(node)
  38 {
  39 }
  40
  41 RenderLayerModelObject::~RenderLayerModelObject()
  42 {
  43     // Our layer should have been destroyed and cleared by now
  44     ASSERT(!hasLayer());
  45     ASSERT(!m_layer);
  46 }
  47
  48 void RenderLayerModelObject::destroyLayer()
  49 {
  50     setHasLayer(false);
  51     m_layer = nullptr;
  52 }
  53
  54 void RenderLayerModelObject::createLayer(LayerType type)
  55 {
  56     ASSERT(!m_layer);
  57     m_layer = adoptPtr(new RenderLayer(this, type));
  58     setHasLayer(true);
  59     m_layer->insertOnlyThisLayer();
  60 }
  61
  62 bool RenderLayerModelObject::hasSelfPaintingLayer() const
  63 {
  64     return m_layer && m_layer->isSelfPaintingLayer();
  65 }
  66
  67 ScrollableArea* RenderLayerModelObject::scrollableArea() const
  68 {
  69     return m_layer ? m_layer->scrollableArea() : 0;
  70 }
  71
  72 void RenderLayerModelObject::willBeDestroyed()
  73 {
  74     if (isPositioned()) {
  75         // Don't use this->view() because the document's renderView has been set to 0 during destruction.
  76         if (LocalFrame* frame = this->frame()) {
  77             if (FrameView* frameView = frame->view()) {
  78                 if (style()->hasViewportConstrainedPosition())
  79                     frameView->removeViewportConstrainedObject(this);
  80             }
  81         }
  82     }
  83
  84     RenderObject::willBeDestroyed();
  85
  86     destroyLayer();
  87 }
  88
  89 void RenderLayerModelObject::styleWillChange(StyleDifference diff, const RenderStyle& newStyle)
  90 {
  91     s_wasFloating = isFloating();
  92
  93     if (RenderStyle* oldStyle = style()) {
  94         if (parent() && diff.needsPaintInvalidationLayer()) {
  95             if (oldStyle->hasClip() != newStyle.hasClip()
  96                 || oldStyle->clip() != newStyle.clip())
  97                 layer()->clipper().clearClipRectsIncludingDescendants();
  98         }
  99     }
 100
 101     RenderObject::styleWillChange(diff, newStyle);
 102 }
 103
 104 void RenderLayerModelObject::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
 105 {
 106     bool hadTransform = hasTransform();
 107     bool hadLayer = hasLayer();
 108     bool layerWasSelfPainting = hadLayer && layer()->isSelfPaintingLayer();
 109
 110     RenderObject::styleDidChange(diff, oldStyle);
 111     updateFromStyle();
 112
 113     LayerType type = layerTypeRequired();
 114     if (type != NoLayer) {
 115         if (!layer() && layerCreationAllowedForSubtree()) {
 116             if (s_wasFloating && isFloating())
 117                 setChildNeedsLayout();
 118             createLayer(type);
 119             if (parent() && !needsLayout()) {
 120                 // FIXME: This invalidation is overly broad. We should update to
 121                 // do the correct invalidation at RenderStyle::diff time. crbug.com/349061
 122                 layer()->renderer()->setShouldDoFullPaintInvalidation(true);
 123                 // FIXME: We should call a specialized version of this function.
 124                 layer()->updateLayerPositionsAfterLayout();
 125             }
 126         }
 127     } else if (layer() && layer()->parent()) {
 128         setHasTransform(false); // Either a transform wasn't specified or the object doesn't support transforms, so just null out the bit.
 129         setHasReflection(false);
 130         layer()->removeOnlyThisLayer(); // calls destroyLayer() which clears m_layer
 131         if (s_wasFloating && isFloating())
 132             setChildNeedsLayout();
 133         if (hadTransform)
 134             setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation();
 135     }
 136
 137     if (layer()) {
 138         // FIXME: Ideally we shouldn't need this setter but we can't easily infer an overflow-only layer
 139         // from the style.
 140         layer()->setLayerType(type);
 141
 142         layer()->styleChanged(diff, oldStyle);
 143         if (hadLayer && layer()->isSelfPaintingLayer() != layerWasSelfPainting)
 144             setChildNeedsLayout();
 145     }
 146
 147     if (FrameView *frameView = view()->frameView()) {
 148         bool newStyleIsViewportConstained = style()->hasViewportConstrainedPosition();
 149         bool oldStyleIsViewportConstrained = oldStyle && oldStyle->hasViewportConstrainedPosition();
 150         if (newStyleIsViewportConstained != oldStyleIsViewportConstrained) {
 151             if (newStyleIsViewportConstained && layer())
 152                 frameView->addViewportConstrainedObject(this);
 153             else
 154                 frameView->removeViewportConstrainedObject(this);
 155         }
 156     }
 157 }
 158
 159 void RenderLayerModelObject::addLayerHitTestRects(LayerHitTestRects& rects, const RenderLayer* currentLayer, const LayoutPoint& layerOffset, const LayoutRect& containerRect) const
 160 {
 161     if (hasLayer()) {
 162         if (isRenderView()) {
 163             // RenderView is handled with a special fast-path, but it needs to know the current layer.
 164             RenderObject::addLayerHitTestRects(rects, layer(), LayoutPoint(), LayoutRect());
 165         } else {
 166             // Since a RenderObject never lives outside it's container RenderLayer, we can switch
 167             // to marking entire layers instead. This may sometimes mark more than necessary (when
 168             // a layer is made of disjoint objects) but in practice is a significant performance
 169             // savings.
 170             layer()->addLayerHitTestRects(rects);
 171         }
 172     } else {
 173         RenderObject::addLayerHitTestRects(rects, currentLayer, layerOffset, containerRect);
 174     }
 175 }
 176
 177 InvalidationReason RenderLayerModelObject::invalidatePaintIfNeeded(const PaintInvalidationState& paintInvalidationState, const RenderLayerModelObject& newPaintInvalidationContainer)
 178 {
 179     const LayoutRect oldPaintInvalidationRect = previousPaintInvalidationRect();
 180     const LayoutPoint oldPositionFromPaintInvalidationContainer = previousPositionFromPaintInvalidationContainer();
 181     setPreviousPaintInvalidationRect(boundsRectForPaintInvalidation(&newPaintInvalidationContainer, &paintInvalidationState));
 182     setPreviousPositionFromPaintInvalidationContainer(RenderLayer::positionFromPaintInvalidationContainer(this, &newPaintInvalidationContainer, &paintInvalidationState));
 183
 184     // If we are set to do a full paint invalidation that means the RenderView will issue
 185     // paint invalidations. We can then skip issuing of paint invalidations for the child
 186     // renderers as they'll be covered by the RenderView.
 187     if (view()->doingFullPaintInvalidation())
 188         return InvalidationNone;
 189
 190     return RenderObject::invalidatePaintIfNeeded(newPaintInvalidationContainer, oldPaintInvalidationRect, oldPositionFromPaintInvalidationContainer, paintInvalidationState);
 191 }
 192
 193 void RenderLayerModelObject::invalidateTreeIfNeeded(const PaintInvalidationState& paintInvalidationState)
 194 {
 195     // FIXME: SVG should probably also go through this unified paint invalidation system.
 196     ASSERT(!needsLayout());
 197
 198     if (!shouldCheckForPaintInvalidation(paintInvalidationState))
 199         return;
 200
 201     bool establishesNewPaintInvalidationContainer = isPaintInvalidationContainer();
 202     const RenderLayerModelObject& newPaintInvalidationContainer = *adjustCompositedContainerForSpecialAncestors(establishesNewPaintInvalidationContainer ? this : &paintInvalidationState.paintInvalidationContainer());
 203     ASSERT(&newPaintInvalidationContainer == containerForPaintInvalidation());
 204
 205     InvalidationReason reason = invalidatePaintIfNeeded(paintInvalidationState, newPaintInvalidationContainer);
 206
 207     PaintInvalidationState childTreeWalkState(paintInvalidationState, *this, newPaintInvalidationContainer);
 208     if (reason == InvalidationLocationChange || reason == InvalidationFull)
 209         childTreeWalkState.setForceCheckForPaintInvalidation();
 210     RenderObject::invalidateTreeIfNeeded(childTreeWalkState);
 211 }
 212
 213 } // namespace blink
 214