1/* 2 * Copyright (C) 2012 Google 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 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 17 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 21 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef TextAutosizer_h 27#define TextAutosizer_h 28 29#if ENABLE(TEXT_AUTOSIZING) 30 31#include "HTMLNames.h" 32#include "WritingMode.h" 33#include <wtf/Noncopyable.h> 34#include <wtf/PassOwnPtr.h> 35 36namespace WebCore { 37 38class Document; 39class RenderBlock; 40class RenderObject; 41class RenderText; 42struct TextAutosizingWindowInfo; 43struct TextAutosizingClusterInfo; 44 45class TextAutosizer { 46 WTF_MAKE_NONCOPYABLE(TextAutosizer); 47 48public: 49 static PassOwnPtr<TextAutosizer> create(Document* document) { return adoptPtr(new TextAutosizer(document)); } 50 51 virtual ~TextAutosizer(); 52 53 bool processSubtree(RenderObject* layoutRoot); 54 void recalculateMultipliers(); 55 56 static float computeAutosizedFontSize(float specifiedSize, float multiplier); 57 58private: 59 enum TraversalDirection { 60 FirstToLast, 61 LastToFirst 62 }; 63 64 explicit TextAutosizer(Document*); 65 66 float clusterMultiplier(WritingMode, const TextAutosizingWindowInfo&, float textWidth) const; 67 68 void processClusterInternal(TextAutosizingClusterInfo&, RenderBlock* container, RenderObject* subtreeRoot, const TextAutosizingWindowInfo&, float multiplier); 69 void processCluster(TextAutosizingClusterInfo&, RenderBlock* container, RenderObject* subtreeRoot, const TextAutosizingWindowInfo&); 70 void processCompositeCluster(Vector<TextAutosizingClusterInfo>&, const TextAutosizingWindowInfo&); 71 void processContainer(float multiplier, RenderBlock* container, TextAutosizingClusterInfo&, RenderObject* subtreeRoot, const TextAutosizingWindowInfo&); 72 73 void setMultiplier(RenderObject*, float); 74 75 static bool isAutosizingContainer(const RenderObject*); 76 static bool isNarrowDescendant(const RenderBlock*, TextAutosizingClusterInfo& parentClusterInfo); 77 static bool isWiderDescendant(const RenderBlock*, const TextAutosizingClusterInfo& parentClusterInfo); 78 static bool isIndependentDescendant(const RenderBlock*); 79 static bool isAutosizingCluster(const RenderBlock*, TextAutosizingClusterInfo& parentClusterInfo); 80 81 static bool containerShouldBeAutosized(const RenderBlock* container); 82 static bool containerContainsOneOfTags(const RenderBlock* cluster, const Vector<QualifiedName>& tags); 83 static bool containerIsRowOfLinks(const RenderObject* container); 84 static bool contentHeightIsConstrained(const RenderBlock* container); 85 static bool clusterShouldBeAutosized(TextAutosizingClusterInfo&, float blockWidth); 86 static bool compositeClusterShouldBeAutosized(Vector<TextAutosizingClusterInfo>&, float blockWidth); 87 static void measureDescendantTextWidth(const RenderBlock* container, TextAutosizingClusterInfo&, float minTextWidth, float& textWidth); 88 89 // Use to traverse the tree of descendants, excluding descendants of containers (but returning the containers themselves). 90 static RenderObject* nextInPreOrderSkippingDescendantsOfContainers(const RenderObject*, const RenderObject* stayWithin); 91 92 static const RenderBlock* findDeepestBlockContainingAllText(const RenderBlock* cluster); 93 94 // Depending on the traversal direction specified, finds the first or the last leaf text node child that doesn't 95 // belong to any cluster. 96 static const RenderObject* findFirstTextLeafNotInCluster(const RenderObject*, size_t& depth, TraversalDirection); 97 98 // Returns groups of narrow descendants of a given autosizing cluster. The groups are combined 99 // by the difference between the width of the descendant and the width of the parent cluster's 100 // |blockContainingAllText|. 101 static void getNarrowDescendantsGroupedByWidth(const TextAutosizingClusterInfo& parentClusterInfo, Vector<Vector<TextAutosizingClusterInfo> >&); 102 103 Document* m_document; 104}; 105 106} // namespace WebCore 107 108#endif // ENABLE(TEXT_AUTOSIZING) 109 110#endif // TextAutosizer_h 111