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 "ChromeClient.h" 30 #include "RenderLayer.h" 31 #include "RenderLayerBacking.h" 32 33 namespace WebCore { 34 35 #define PROFILE_LAYER_REBUILD 0 36 37 class GraphicsLayer; 38 class RenderEmbeddedObject; 39 class RenderPart; 40 #if ENABLE(VIDEO) 41 class RenderVideo; 42 #endif 43 44 enum CompositingUpdateType { 45 CompositingUpdateAfterLayoutOrStyleChange, 46 CompositingUpdateOnPaitingOrHitTest, 47 CompositingUpdateOnScroll 48 }; 49 50 // RenderLayerCompositor manages the hierarchy of 51 // composited RenderLayers. It determines which RenderLayers 52 // become compositing, and creates and maintains a hierarchy of 53 // GraphicsLayers based on the RenderLayer painting order. 54 // 55 // There is one RenderLayerCompositor per RenderView. 56 57 class RenderLayerCompositor : public GraphicsLayerClient { 58 public: 59 RenderLayerCompositor(RenderView*); 60 ~RenderLayerCompositor(); 61 62 // Return true if this RenderView is in "compositing mode" (i.e. has one or more 63 // composited RenderLayers) inCompositingMode()64 bool inCompositingMode() const { return m_compositing; } 65 // This will make a compositing layer at the root automatically, and hook up to 66 // the native view/window system. 67 void enableCompositingMode(bool enable = true); 68 69 // Returns true if the accelerated compositing is enabled hasAcceleratedCompositing()70 bool hasAcceleratedCompositing() const { return m_hasAcceleratedCompositing; } 71 72 bool canRender3DTransforms() const; 73 74 // Copy the accelerated compositing related flags from Settings 75 void cacheAcceleratedCompositingFlags(); 76 77 // Called when the layer hierarchy needs to be updated (compositing layers have been 78 // created, destroyed or re-parented). 79 void setCompositingLayersNeedRebuild(bool needRebuild = true); compositingLayersNeedRebuild()80 bool compositingLayersNeedRebuild() const { return m_compositingLayersNeedRebuild; } 81 82 // Controls whether or not to consult geometry when deciding which layers need 83 // to be composited. Defaults to true. setCompositingConsultsOverlap(bool b)84 void setCompositingConsultsOverlap(bool b) { m_compositingConsultsOverlap = b; } compositingConsultsOverlap()85 bool compositingConsultsOverlap() const { return m_compositingConsultsOverlap; } 86 87 // GraphicsLayers buffer state, which gets pushed to the underlying platform layers 88 // at specific times. 89 void scheduleLayerFlush(); 90 void flushPendingLayerChanges(); isFlushingLayers()91 bool isFlushingLayers() const { return m_flushingLayers; } 92 93 // flushPendingLayerChanges() flushes the entire GraphicsLayer tree, which can cross frame boundaries. 94 // This call returns the rootmost compositor that is being flushed (including self). 95 RenderLayerCompositor* enclosingCompositorFlushingLayers() const; 96 97 // Rebuild the tree of compositing layers 98 void updateCompositingLayers(CompositingUpdateType = CompositingUpdateAfterLayoutOrStyleChange, RenderLayer* updateRoot = 0); 99 // This is only used when state changes and we do not exepect a style update or layout to happen soon (e.g. when 100 // we discover that an iframe is overlapped during painting). 101 void scheduleCompositingLayerUpdate(); 102 bool compositingLayerUpdatePending() const; 103 104 // Update the compositing state of the given layer. Returns true if that state changed. 105 enum CompositingChangeRepaint { CompositingChangeRepaintNow, CompositingChangeWillRepaintLater }; 106 bool updateLayerCompositingState(RenderLayer*, CompositingChangeRepaint = CompositingChangeRepaintNow); 107 108 // Update the geometry for compositing children of compositingAncestor. 109 void updateCompositingDescendantGeometry(RenderLayer* compositingAncestor, RenderLayer* layer, RenderLayerBacking::UpdateDepth); 110 111 // Whether layer's backing needs a graphics layer to do clipping by an ancestor (non-stacking-context parent with overflow). 112 bool clippedByAncestor(RenderLayer*) const; 113 // Whether layer's backing needs a graphics layer to clip z-order children of the given layer. 114 bool clipsCompositingDescendants(const RenderLayer*) const; 115 116 // Whether the given layer needs an extra 'contents' layer. 117 bool needsContentsCompositingLayer(const RenderLayer*) const; 118 // Return the bounding box required for compositing layer and its childern, relative to ancestorLayer. 119 // If layerBoundingBox is not 0, on return it contains the bounding box of this layer only. 120 IntRect calculateCompositedBounds(const RenderLayer* layer, const RenderLayer* ancestorLayer); 121 122 // Repaint the appropriate layers when the given RenderLayer starts or stops being composited. 123 void repaintOnCompositingChange(RenderLayer*); 124 125 // Notify us that a layer has been added or removed 126 void layerWasAdded(RenderLayer* parent, RenderLayer* child); 127 void layerWillBeRemoved(RenderLayer* parent, RenderLayer* child); 128 129 // Get the nearest ancestor layer that has overflow or clip, but is not a stacking context 130 RenderLayer* enclosingNonStackingClippingLayer(const RenderLayer* layer) const; 131 132 // Repaint parts of all composited layers that intersect the given absolute rectangle. 133 void repaintCompositedLayersAbsoluteRect(const IntRect&); 134 135 RenderLayer* rootRenderLayer() const; 136 GraphicsLayer* rootPlatformLayer() const; 137 138 enum RootLayerAttachment { 139 RootLayerUnattached, 140 RootLayerAttachedViaChromeClient, 141 RootLayerAttachedViaEnclosingFrame 142 }; 143 rootLayerAttachment()144 RootLayerAttachment rootLayerAttachment() const { return m_rootLayerAttachment; } 145 void updateRootLayerAttachment(); 146 void updateRootLayerPosition(); 147 148 void didMoveOnscreen(); 149 void willMoveOffscreen(); 150 151 void didStartAcceleratedAnimation(CSSPropertyID); 152 153 #if ENABLE(VIDEO) 154 // Use by RenderVideo to ask if it should try to use accelerated compositing. 155 bool canAccelerateVideoRendering(RenderVideo*) const; 156 #endif 157 158 // Walk the tree looking for layers with 3d transforms. Useful in case you need 159 // to know if there is non-affine content, e.g. for drawing into an image. 160 bool has3DContent() const; 161 162 // Most platforms connect compositing layer trees between iframes and their parent document. 163 // Some (currently just Mac) allow iframes to do their own compositing. 164 static bool allowsIndependentlyCompositedFrames(const FrameView*); 165 bool shouldPropagateCompositingToEnclosingFrame() const; 166 167 HTMLFrameOwnerElement* enclosingFrameElement() const; 168 169 static RenderLayerCompositor* frameContentsCompositor(RenderPart*); 170 // Return true if the layers changed. 171 static bool parentFrameContentLayers(RenderPart*); 172 173 // Update the geometry of the layers used for clipping and scrolling in frames. 174 void frameViewDidChangeLocation(const IntPoint& contentsOffset); 175 void frameViewDidChangeSize(); 176 void frameViewDidScroll(const IntPoint& = IntPoint()); 177 178 String layerTreeAsText(bool showDebugInfo = false); 179 180 // These are named to avoid conflicts with the functions in GraphicsLayerClient 181 // These return the actual internal variables. compositorShowDebugBorders()182 bool compositorShowDebugBorders() const { return m_showDebugBorders; } compositorShowRepaintCounter()183 bool compositorShowRepaintCounter() const { return m_showRepaintCounter; } 184 185 void updateContentsScale(float, RenderLayer* = 0); 186 layerForHorizontalScrollbar()187 GraphicsLayer* layerForHorizontalScrollbar() const { return m_layerForHorizontalScrollbar.get(); } layerForVerticalScrollbar()188 GraphicsLayer* layerForVerticalScrollbar() const { return m_layerForVerticalScrollbar.get(); } layerForScrollCorner()189 GraphicsLayer* layerForScrollCorner() const { return m_layerForScrollCorner.get(); } 190 191 private: 192 // GraphicsLayerClient Implementation notifyAnimationStarted(const GraphicsLayer *,double)193 virtual void notifyAnimationStarted(const GraphicsLayer*, double) { } notifySyncRequired(const GraphicsLayer *)194 virtual void notifySyncRequired(const GraphicsLayer*) { scheduleLayerFlush(); } 195 virtual void paintContents(const GraphicsLayer*, GraphicsContext&, GraphicsLayerPaintingPhase, const IntRect&); 196 197 // These calls return false always. They are saying that the layers associated with this client 198 // (the clipLayer and scrollLayer) should never show debugging info. showDebugBorders()199 virtual bool showDebugBorders() const { return false; } showRepaintCounter()200 virtual bool showRepaintCounter() const { return false; } 201 202 // Whether the given RL needs a compositing layer. 203 bool needsToBeComposited(const RenderLayer*) const; 204 // Whether the layer has an intrinsic need for compositing layer. 205 bool requiresCompositingLayer(const RenderLayer*) const; 206 // Whether the layer could ever be composited. 207 bool canBeComposited(const RenderLayer*) const; 208 209 // Make or destroy the backing for this layer; returns true if backing changed. 210 bool updateBacking(RenderLayer*, CompositingChangeRepaint shouldRepaint); 211 212 // Repaint the given rect (which is layer's coords), and regions of child layers that intersect that rect. 213 void recursiveRepaintLayerRect(RenderLayer* layer, const IntRect& rect); 214 215 typedef HashMap<RenderLayer*, IntRect> OverlapMap; 216 static void addToOverlapMap(OverlapMap&, RenderLayer*, IntRect& layerBounds, bool& boundsComputed); 217 static bool overlapsCompositedLayers(OverlapMap&, const IntRect& layerBounds); 218 219 void updateCompositingLayersTimerFired(Timer<RenderLayerCompositor>*); 220 221 #if ENABLE(COMPOSITED_FIXED_ELEMENTS) 222 bool checkForPositionedElements(Vector<RenderLayer*>* list); 223 #endif 224 225 // Returns true if any layer's compositing changed 226 void computeCompositingRequirements(RenderLayer*, OverlapMap*, struct CompositingState&, bool& layersChanged); 227 228 // Recurses down the tree, parenting descendant compositing layers and collecting an array of child layers for the current compositing layer. 229 void rebuildCompositingLayerTree(RenderLayer* layer, const struct CompositingState&, Vector<GraphicsLayer*>& childGraphicsLayersOfEnclosingLayer); 230 231 // Recurses down the tree, updating layer geometry only. 232 void updateLayerTreeGeometry(RenderLayer*); 233 234 // Hook compositing layers together 235 void setCompositingParent(RenderLayer* childLayer, RenderLayer* parentLayer); 236 void removeCompositedChildren(RenderLayer*); 237 238 bool layerHas3DContent(const RenderLayer*) const; 239 240 void ensureRootPlatformLayer(); 241 void destroyRootPlatformLayer(); 242 243 void attachRootPlatformLayer(RootLayerAttachment); 244 void detachRootPlatformLayer(); 245 246 void rootLayerAttachmentChanged(); 247 248 void updateOverflowControlsLayers(); 249 250 void scheduleNeedsStyleRecalc(Element*); 251 void notifyIFramesOfCompositingChange(); 252 253 // Whether a running transition or animation enforces the need for a compositing layer. 254 bool requiresCompositingForAnimation(RenderObject*) const; 255 bool requiresCompositingForTransform(RenderObject*) const; 256 bool requiresCompositingForVideo(RenderObject*) const; 257 bool requiresCompositingForCanvas(RenderObject*) const; 258 bool requiresCompositingForPlugin(RenderObject*) const; 259 bool requiresCompositingForFrame(RenderObject*) const; 260 bool requiresCompositingWhenDescendantsAreCompositing(RenderObject*) const; 261 bool requiresCompositingForFullScreen(RenderObject*) const; 262 263 #if PLATFORM(ANDROID) 264 // Whether we are using layers for new android features (overflow support, fixed elements) 265 bool requiresCompositingForAndroidLayers(const RenderLayer* layer) const; 266 #endif 267 268 bool requiresScrollLayer(RootLayerAttachment) const; 269 bool requiresHorizontalScrollbarLayer() const; 270 bool requiresVerticalScrollbarLayer() const; 271 bool requiresScrollCornerLayer() const; 272 273 private: 274 RenderView* m_renderView; 275 OwnPtr<GraphicsLayer> m_rootPlatformLayer; 276 Timer<RenderLayerCompositor> m_updateCompositingLayersTimer; 277 278 bool m_hasAcceleratedCompositing; 279 ChromeClient::CompositingTriggerFlags m_compositingTriggers; 280 281 bool m_showDebugBorders; 282 bool m_showRepaintCounter; 283 bool m_compositingConsultsOverlap; 284 285 // When true, we have to wait until layout has happened before we can decide whether to enter compositing mode, 286 // because only then do we know the final size of plugins and iframes. 287 // FIXME: once set, this is never cleared. 288 mutable bool m_compositingDependsOnGeometry; 289 290 bool m_compositing; 291 bool m_compositingLayersNeedRebuild; 292 bool m_flushingLayers; 293 bool m_forceCompositingMode; 294 295 RootLayerAttachment m_rootLayerAttachment; 296 297 // Enclosing clipping layer for iframe content 298 OwnPtr<GraphicsLayer> m_clipLayer; 299 OwnPtr<GraphicsLayer> m_scrollLayer; 300 301 // Enclosing layer for overflow controls and the clipping layer 302 OwnPtr<GraphicsLayer> m_overflowControlsHostLayer; 303 304 // Layers for overflow controls 305 OwnPtr<GraphicsLayer> m_layerForHorizontalScrollbar; 306 OwnPtr<GraphicsLayer> m_layerForVerticalScrollbar; 307 OwnPtr<GraphicsLayer> m_layerForScrollCorner; 308 #if PROFILE_LAYER_REBUILD 309 int m_rootLayerUpdateCount; 310 #endif 311 }; 312 313 314 } // namespace WebCore 315 316 #endif // RenderLayerCompositor_h 317