Home | History | Annotate | Download | only in rendering 
      1 /*
      2  * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org)
      3  *           (C) 1999 Antti Koivisto (koivisto (at) kde.org)
      4  *           (C) 2005 Allan Sandfeld Jensen (kde (at) carewolf.com)
      5  *           (C) 2005, 2006 Samuel Weinig (sam.weinig (at) 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     // FIXME: This assert should be re-enabled when we move paint invalidation to after compositing update. crbug.com/360286
    185     // ASSERT(&newPaintInvalidationContainer == containerForPaintInvalidation());
    186 
    187     InvalidationReason reason = invalidatePaintIfNeeded(paintInvalidationState, newPaintInvalidationContainer);
    188     clearPaintInvalidationState(paintInvalidationState);
    189 
    190     PaintInvalidationState childTreeWalkState(paintInvalidationState, *this, newPaintInvalidationContainer);
    191     if (reason == InvalidationLocationChange || reason == InvalidationFull)
    192         childTreeWalkState.setForceCheckForPaintInvalidation();
    193     invalidatePaintOfSubtreesIfNeeded(childTreeWalkState);
    194 }
    195 
    196 void RenderLayerModelObject::setBackingNeedsPaintInvalidationInRect(const LayoutRect& r) const
    197 {
    198     // https://bugs.webkit.org/show_bug.cgi?id=61159 describes an unreproducible crash here,
    199     // so assert but check that the layer is composited.
    200     ASSERT(compositingState() != NotComposited);
    201 
    202     WebInvalidationDebugAnnotations annotations = WebInvalidationDebugAnnotationsNone;
    203     if (!hadPaintInvalidation())
    204         annotations = WebInvalidationDebugAnnotationsFirstPaint;
    205     // FIXME: The callers assume they are calling a const function but this function has a side effect.
    206     const_cast<RenderLayerModelObject*>(this)->setHadPaintInvalidation();
    207 
    208     // FIXME: generalize accessors to backing GraphicsLayers so that this code is squashing-agnostic.
    209     if (layer()->groupedMapping()) {
    210         LayoutRect paintInvalidationRect = r;
    211         if (GraphicsLayer* squashingLayer = layer()->groupedMapping()->squashingLayer()) {
    212             // Note: the subpixel accumulation of layer() does not need to be added here. It is already taken into account.
    213             squashingLayer->setNeedsDisplayInRect(pixelSnappedIntRect(paintInvalidationRect), annotations);
    214         }
    215     } else {
    216         layer()->compositedLayerMapping()->setContentsNeedDisplayInRect(r, annotations);
    217     }
    218 }
    219 
    220 } // namespace blink
    221 
    222