1 /* 2 * Copyright (C) 2009 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef RenderLayerCompositor_h 27 #define RenderLayerCompositor_h 28 29 #include "RenderLayer.h" 30 #include "RenderLayerBacking.h" 31 32 namespace WebCore { 33 34 #define PROFILE_LAYER_REBUILD 0 35 36 class GraphicsLayer; 37 #if ENABLE(VIDEO) 38 class RenderVideo; 39 #endif 40 41 enum CompositingUpdateType { 42 CompositingUpdateAfterLayoutOrStyleChange, 43 CompositingUpdateOnPaitingOrHitTest, 44 CompositingUpdateOnScroll 45 }; 46 47 // RenderLayerCompositor manages the hierarchy of 48 // composited RenderLayers. It determines which RenderLayers 49 // become compositing, and creates and maintains a hierarchy of 50 // GraphicsLayers based on the RenderLayer painting order. 51 // 52 // There is one RenderLayerCompositor per RenderView. 53 54 class RenderLayerCompositor { 55 public: 56 RenderLayerCompositor(RenderView*); 57 ~RenderLayerCompositor(); 58 59 // Return true if this RenderView is in "compositing mode" (i.e. has one or more 60 // composited RenderLayers) inCompositingMode()61 bool inCompositingMode() const { return m_compositing; } 62 // This will make a compositing layer at the root automatically, and hook up to 63 // the native view/window system. 64 void enableCompositingMode(bool enable = true); 65 66 // Returns true if the accelerated compositing is enabled hasAcceleratedCompositing()67 bool hasAcceleratedCompositing() const { return m_hasAcceleratedCompositing; } 68 showDebugBorders()69 bool showDebugBorders() const { return m_showDebugBorders; } showRepaintCounter()70 bool showRepaintCounter() const { return m_showRepaintCounter; } 71 72 // Copy the accelerated compositing related flags from Settings 73 void cacheAcceleratedCompositingFlags(); 74 75 // Called when the layer hierarchy needs to be updated (compositing layers have been 76 // created, destroyed or re-parented). 77 void setCompositingLayersNeedRebuild(bool needRebuild = true); compositingLayersNeedRebuild()78 bool compositingLayersNeedRebuild() const { return m_compositingLayersNeedRebuild; } 79 80 // Controls whether or not to consult geometry when deciding which layers need 81 // to be composited. Defaults to true. setCompositingConsultsOverlap(bool b)82 void setCompositingConsultsOverlap(bool b) { m_compositingConsultsOverlap = b; } compositingConsultsOverlap()83 bool compositingConsultsOverlap() const { return m_compositingConsultsOverlap; } 84 85 void scheduleSync(); 86 87 // Rebuild the tree of compositing layers 88 void updateCompositingLayers(CompositingUpdateType = CompositingUpdateAfterLayoutOrStyleChange, RenderLayer* updateRoot = 0); 89 90 // Update the compositing state of the given layer. Returns true if that state changed. 91 enum CompositingChangeRepaint { CompositingChangeRepaintNow, CompositingChangeWillRepaintLater }; 92 bool updateLayerCompositingState(RenderLayer*, CompositingChangeRepaint = CompositingChangeRepaintNow); 93 94 // Update the geometry for compositing children of compositingAncestor. 95 void updateCompositingDescendantGeometry(RenderLayer* compositingAncestor, RenderLayer* layer, RenderLayerBacking::UpdateDepth); 96 97 // Whether layer's backing needs a graphics layer to do clipping by an ancestor (non-stacking-context parent with overflow). 98 bool clippedByAncestor(RenderLayer*) const; 99 // Whether layer's backing needs a graphics layer to clip z-order children of the given layer. 100 bool clipsCompositingDescendants(const RenderLayer*) const; 101 102 // Whether the given layer needs an extra 'contents' layer. 103 bool needsContentsCompositingLayer(const RenderLayer*) const; 104 // Return the bounding box required for compositing layer and its childern, relative to ancestorLayer. 105 // If layerBoundingBox is not 0, on return it contains the bounding box of this layer only. 106 IntRect calculateCompositedBounds(const RenderLayer* layer, const RenderLayer* ancestorLayer); 107 108 // Repaint the appropriate layers when the given RenderLayer starts or stops being composited. 109 void repaintOnCompositingChange(RenderLayer*); 110 111 // Notify us that a layer has been added or removed 112 void layerWasAdded(RenderLayer* parent, RenderLayer* child); 113 void layerWillBeRemoved(RenderLayer* parent, RenderLayer* child); 114 115 // Get the nearest ancestor layer that has overflow or clip, but is not a stacking context 116 RenderLayer* enclosingNonStackingClippingLayer(const RenderLayer* layer) const; 117 118 // Repaint parts of all composited layers that intersect the given absolute rectangle. 119 void repaintCompositedLayersAbsoluteRect(const IntRect&); 120 121 RenderLayer* rootRenderLayer() const; 122 GraphicsLayer* rootPlatformLayer() const; 123 124 void didMoveOnscreen(); 125 void willMoveOffscreen(); 126 127 void updateRootLayerPosition(); 128 129 void didStartAcceleratedAnimation(); 130 131 #if ENABLE(VIDEO) 132 // Use by RenderVideo to ask if it should try to use accelerated compositing. 133 bool canAccelerateVideoRendering(RenderVideo*) const; 134 #endif 135 136 // Walk the tree looking for layers with 3d transforms. Useful in case you need 137 // to know if there is non-affine content, e.g. for drawing into an image. 138 bool has3DContent() const; 139 140 private: 141 // Whether the given RL needs a compositing layer. 142 bool needsToBeComposited(const RenderLayer*) const; 143 // Whether the layer has an intrinsic need for compositing layer. 144 bool requiresCompositingLayer(const RenderLayer*) const; 145 146 // Make or destroy the backing for this layer; returns true if backing changed. 147 bool updateBacking(RenderLayer*, CompositingChangeRepaint shouldRepaint); 148 149 // Repaint the given rect (which is layer's coords), and regions of child layers that intersect that rect. 150 void recursiveRepaintLayerRect(RenderLayer* layer, const IntRect& rect); 151 152 typedef HashMap<RenderLayer*, IntRect> OverlapMap; 153 static void addToOverlapMap(OverlapMap&, RenderLayer*, IntRect& layerBounds, bool& boundsComputed); 154 static bool overlapsCompositedLayers(OverlapMap&, const IntRect& layerBounds); 155 156 // Returns true if any layer's compositing changed 157 void computeCompositingRequirements(RenderLayer*, OverlapMap*, struct CompositingState&, bool& layersChanged); 158 159 // Recurses down the tree, parenting descendant compositing layers and collecting an array of child layers for the current compositing layer. 160 void rebuildCompositingLayerTree(RenderLayer* layer, const struct CompositingState&, Vector<GraphicsLayer*>& childGraphicsLayersOfEnclosingLayer); 161 162 // Recurses down the tree, updating layer geometry only. 163 void updateLayerTreeGeometry(RenderLayer*); 164 165 // Hook compositing layers together 166 void setCompositingParent(RenderLayer* childLayer, RenderLayer* parentLayer); 167 void removeCompositedChildren(RenderLayer*); 168 169 void parentInRootLayer(RenderLayer*); 170 171 bool layerHas3DContent(const RenderLayer*) const; 172 173 void ensureRootPlatformLayer(); 174 void destroyRootPlatformLayer(); 175 176 // Whether a running transition or animation enforces the need for a compositing layer. 177 bool requiresCompositingForAnimation(RenderObject*) const; 178 bool requiresCompositingForTransform(RenderObject*) const; 179 bool requiresCompositingForVideo(RenderObject*) const; 180 bool requiresCompositingForCanvas(RenderObject*) const; 181 bool requiresCompositingForPlugin(RenderObject*) const; 182 bool requiresCompositingWhenDescendantsAreCompositing(RenderObject*) const; 183 184 #if PLATFORM(ANDROID) 185 // Whether we are on a mobile site 186 bool requiresCompositingForMobileSites(const RenderLayer* layer) const; 187 #endif 188 189 private: 190 RenderView* m_renderView; 191 OwnPtr<GraphicsLayer> m_rootPlatformLayer; 192 bool m_hasAcceleratedCompositing; 193 bool m_showDebugBorders; 194 bool m_showRepaintCounter; 195 bool m_compositingConsultsOverlap; 196 bool m_compositing; 197 bool m_rootLayerAttached; 198 bool m_compositingLayersNeedRebuild; 199 200 #if PROFILE_LAYER_REBUILD 201 int m_rootLayerUpdateCount; 202 #endif 203 }; 204 205 206 } // namespace WebCore 207 208 #endif // RenderLayerCompositor_h 209