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 #include "HTMLNames.h" 30 #include "platform/text/WritingMode.h" 31 #include "wtf/Noncopyable.h" 32 #include "wtf/PassOwnPtr.h" 33 34 namespace WebCore { 35 36 class Document; 37 class RenderBlock; 38 class RenderObject; 39 class RenderText; 40 struct TextAutosizingWindowInfo; 41 struct TextAutosizingClusterInfo; 42 43 class TextAutosizer FINAL { 44 WTF_MAKE_NONCOPYABLE(TextAutosizer); 45 46 public: create(Document * document)47 static PassOwnPtr<TextAutosizer> create(Document* document) { return adoptPtr(new TextAutosizer(document)); } 48 49 bool processSubtree(RenderObject* layoutRoot); 50 void recalculateMultipliers(); 51 52 static float computeAutosizedFontSize(float specifiedSize, float multiplier); 53 54 private: 55 friend class FastTextAutosizer; 56 57 enum TraversalDirection { 58 FirstToLast, 59 LastToFirst 60 }; 61 62 explicit TextAutosizer(Document*); 63 64 float clusterMultiplier(WritingMode, const TextAutosizingWindowInfo&, float textWidth) const; 65 66 void processClusterInternal(TextAutosizingClusterInfo&, RenderBlock* container, RenderObject* subtreeRoot, const TextAutosizingWindowInfo&, float multiplier); 67 void processCluster(TextAutosizingClusterInfo&, RenderBlock* container, RenderObject* subtreeRoot, const TextAutosizingWindowInfo&); 68 void processCompositeCluster(Vector<TextAutosizingClusterInfo>&, const TextAutosizingWindowInfo&); 69 void processContainer(float multiplier, RenderBlock* container, TextAutosizingClusterInfo&, RenderObject* subtreeRoot, const TextAutosizingWindowInfo&); 70 71 void setMultiplier(RenderObject*, float); 72 void setMultiplierForList(RenderObject* renderer, float multiplier); 73 74 static bool isAutosizingContainer(const RenderObject*); 75 static bool isNarrowDescendant(const RenderBlock*, TextAutosizingClusterInfo& parentClusterInfo); 76 static bool isWiderDescendant(const RenderBlock*, const TextAutosizingClusterInfo& parentClusterInfo); 77 static bool isIndependentDescendant(const RenderBlock*); 78 static bool isAutosizingCluster(const RenderBlock*, TextAutosizingClusterInfo& parentClusterInfo); 79 80 static bool containerShouldBeAutosized(const RenderBlock* container); 81 static bool containerContainsOneOfTags(const RenderBlock* cluster, const Vector<QualifiedName>& tags); 82 static bool containerIsRowOfLinks(const RenderObject* container); 83 static bool contentHeightIsConstrained(const RenderBlock* container); 84 static bool clusterShouldBeAutosized(TextAutosizingClusterInfo&, float blockWidth); 85 static bool compositeClusterShouldBeAutosized(Vector<TextAutosizingClusterInfo>&, float blockWidth); 86 static void measureDescendantTextWidth(const RenderBlock* container, TextAutosizingClusterInfo&, float minTextWidth, float& textWidth); 87 88 // Use to traverse the tree of descendants, excluding descendants of containers (but returning the containers themselves). 89 static RenderObject* nextInPreOrderSkippingDescendantsOfContainers(const RenderObject*, const RenderObject* stayWithin); 90 91 static const RenderBlock* findDeepestBlockContainingAllText(const RenderBlock* cluster); 92 93 // Depending on the traversal direction specified, finds the first or the last leaf text node child that doesn't 94 // belong to any cluster. 95 static const RenderObject* findFirstTextLeafNotInCluster(const RenderObject*, size_t& depth, TraversalDirection); 96 97 // Returns groups of narrow descendants of a given autosizing cluster. The groups are combined 98 // by the difference between the width of the descendant and the width of the parent cluster's 99 // |blockContainingAllText|. 100 static void getNarrowDescendantsGroupedByWidth(const TextAutosizingClusterInfo& parentClusterInfo, Vector<Vector<TextAutosizingClusterInfo> >&); 101 102 Document* m_document; 103 }; 104 105 } // namespace WebCore 106 107 #endif // TextAutosizer_h 108