1 /* 2 * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved. 3 * Copyright (C) 2013 Intel Corporation. All rights reserved. 4 * 5 * Portions are Copyright (C) 1998 Netscape Communications Corporation. 6 * 7 * Other contributors: 8 * Robert O'Callahan <roc+@cs.cmu.edu> 9 * David Baron <dbaron@fas.harvard.edu> 10 * Christian Biesinger <cbiesinger@web.de> 11 * Randall Jesup <rjesup@wgate.com> 12 * Roland Mainz <roland.mainz@informatik.med.uni-giessen.de> 13 * Josh Soref <timeless@mac.com> 14 * Boris Zbarsky <bzbarsky@mit.edu> 15 * 16 * This library is free software; you can redistribute it and/or 17 * modify it under the terms of the GNU Lesser General Public 18 * License as published by the Free Software Foundation; either 19 * version 2.1 of the License, or (at your option) any later version. 20 * 21 * This library is distributed in the hope that it will be useful, 22 * but WITHOUT ANY WARRANTY; without even the implied warranty of 23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 24 * Lesser General Public License for more details. 25 * 26 * You should have received a copy of the GNU Lesser General Public 27 * License along with this library; if not, write to the Free Software 28 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 29 * 30 * Alternatively, the contents of this file may be used under the terms 31 * of either the Mozilla Public License Version 1.1, found at 32 * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public 33 * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html 34 * (the "GPL"), in which case the provisions of the MPL or the GPL are 35 * applicable instead of those above. If you wish to allow use of your 36 * version of this file only under the terms of one of those two 37 * licenses (the MPL or the GPL) and not to allow others to use your 38 * version of this file under the LGPL, indicate your decision by 39 * deletingthe provisions above and replace them with the notice and 40 * other provisions required by the MPL or the GPL, as the case may be. 41 * If you do not delete the provisions above, a recipient may use your 42 * version of this file under any of the LGPL, the MPL or the GPL. 43 */ 44 45 #ifndef RenderLayerClipper_h 46 #define RenderLayerClipper_h 47 48 #include "core/rendering/ClipRect.h" 49 #include "core/rendering/RenderBox.h" // For OverlayScrollbarSizeRelevancy. 50 51 namespace WebCore { 52 53 class RenderLayer; 54 55 struct ClipRectsContext { 56 ClipRectsContext(const RenderLayer* inRootLayer, ClipRectsType inClipRectsType, OverlayScrollbarSizeRelevancy inOverlayScrollbarSizeRelevancy = IgnoreOverlayScrollbarSize, ShouldRespectOverflowClip inRespectOverflowClip = RespectOverflowClip, const LayoutSize& inSubPixelAccumulation = LayoutSize()) rootLayerClipRectsContext57 : rootLayer(inRootLayer) 58 , clipRectsType(inClipRectsType) 59 , overlayScrollbarSizeRelevancy(inOverlayScrollbarSizeRelevancy) 60 , respectOverflowClip(inRespectOverflowClip) 61 , subPixelAccumulation(inSubPixelAccumulation) 62 { } 63 const RenderLayer* rootLayer; 64 ClipRectsType clipRectsType; 65 OverlayScrollbarSizeRelevancy overlayScrollbarSizeRelevancy; 66 ShouldRespectOverflowClip respectOverflowClip; 67 LayoutSize subPixelAccumulation; 68 }; 69 70 class RenderLayerClipper FINAL { 71 WTF_MAKE_NONCOPYABLE(RenderLayerClipper); 72 public: RenderLayerClipper(RenderLayerModelObject & renderer)73 explicit RenderLayerClipper(RenderLayerModelObject& renderer) 74 : m_renderer(renderer) 75 , m_compositingClipRectsDirty(false) 76 { 77 } 78 clipRects(const ClipRectsContext & context)79 ClipRects* clipRects(const ClipRectsContext& context) const 80 { 81 ASSERT(context.clipRectsType < NumCachedClipRectsTypes); 82 return m_clipRectsCache ? m_clipRectsCache->getClipRects(context.clipRectsType, context.respectOverflowClip).get() : 0; 83 } 84 85 // Compute and cache clip rects computed with the given layer as the root 86 void updateClipRects(const ClipRectsContext&); 87 88 void clearClipRectsIncludingDescendants(ClipRectsType typeToClear = AllClipRectTypes); 89 void clearClipRects(ClipRectsType typeToClear = AllClipRectTypes); 90 91 void setCompositingClipRectsDirty(); 92 93 LayoutRect childrenClipRect() const; // Returns the foreground clip rect of the layer in the document's coordinate space. 94 LayoutRect localClipRect() const; // Returns the background clip rect of the layer in the local coordinate space. 95 96 ClipRect backgroundClipRect(const ClipRectsContext&) const; 97 98 // FIXME: The following functions should be private. 99 100 // This method figures out our layerBounds in coordinates relative to 101 // |rootLayer}. It also computes our background and foreground clip rects 102 // for painting/event handling. 103 // Pass offsetFromRoot if known. 104 void calculateRects(const ClipRectsContext&, const LayoutRect& paintDirtyRect, LayoutRect& layerBounds, 105 ClipRect& backgroundRect, ClipRect& foregroundRect, ClipRect& outlineRect, const LayoutPoint* offsetFromRoot = 0) const; 106 107 // Compute and return the clip rects. If useCached is true, will used previously computed clip rects on ancestors 108 // (rather than computing them all from scratch up the parent chain). 109 void calculateClipRects(const ClipRectsContext&, ClipRects&) const; 110 111 private: 112 void parentClipRects(const ClipRectsContext&, ClipRects&) const; 113 114 // The layer relative to which clipping rects for this layer are computed. 115 RenderLayer* clippingRootForPainting() const; 116 117 bool isClippingRootForContext(const ClipRectsContext&) const; 118 119 // FIXME: Could this be a RenderBox? 120 RenderLayerModelObject& m_renderer; 121 OwnPtr<ClipRectsCache> m_clipRectsCache; 122 unsigned m_compositingClipRectsDirty : 1; 123 }; 124 125 } // namespace WebCore 126 127 #endif // RenderLayerClipper_h 128