1/* 2 * Copyright (C) 2012 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 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 27#ifndef RenderRegionSet_h 28#define RenderRegionSet_h 29 30#include "RenderRegion.h" 31#include "RenderBoxRegionInfo.h" 32 33namespace WebCore { 34 35class RenderFlowThread; 36 37// RenderRegionSet represents a set of regions that all have the same width and height. It is a "composite region box" that 38// can be used to represent a single run of contiguous regions. 39// 40// By combining runs of same-size columns or pages into a single object, we significantly reduce the number of unique RenderObjects 41// required to represent those objects. 42// 43// This class is abstract and is only intended for use by renderers that generate anonymous runs of identical regions, i.e., 44// columns and printing. RenderMultiColumnSet and RenderPageSet represent runs of columns and pages respectively. 45// 46// FIXME: For now we derive from RenderRegion, but this may change at some point. 47 48class RenderRegionSet : public RenderRegion { 49public: 50 void expandToEncompassFlowThreadContentsIfNeeded(); 51 52protected: 53 RenderRegionSet(Document&, PassRef<RenderStyle>, RenderFlowThread&); 54 55private: 56 virtual void installFlowThread() override final; 57 58 virtual const char* renderName() const = 0; 59 60 virtual bool isRenderRegionSet() const override final { return true; } 61}; 62 63} // namespace WebCore 64 65#endif // RenderRegionSet_h 66 67