1 /* 2 * Copyright (C) 2003, 2006, 2008, 2011 Apple Inc. All rights reserved. 3 * Copyright (C) 2008 Holger Hans Peter Freyther 4 * Copyright (C) 2014 Google Inc. All rights reserved. 5 * 6 * This library is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Library General Public 8 * License as published by the Free Software Foundation; either 9 * version 2 of the License, or (at your option) any later version. 10 * 11 * This library is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Library General Public License for more details. 15 * 16 * You should have received a copy of the GNU Library General Public License 17 * along with this library; see the file COPYING.LIB. If not, write to 18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 * Boston, MA 02110-1301, USA. 20 * 21 */ 22 23 #ifndef WidthIterator_h 24 #define WidthIterator_h 25 26 #include "platform/PlatformExport.h" 27 #include "platform/fonts/SVGGlyph.h" 28 #include "platform/text/TextRun.h" 29 #include "wtf/HashSet.h" 30 #include "wtf/unicode/Unicode.h" 31 #include "wtf/Vector.h" 32 33 namespace blink { 34 35 class Font; 36 class GlyphBuffer; 37 class SimpleFontData; 38 class TextRun; 39 struct GlyphData; 40 41 struct PLATFORM_EXPORT WidthIterator { 42 WTF_MAKE_FAST_ALLOCATED; 43 public: 44 WidthIterator(const Font*, const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, bool accountForGlyphBounds = false, bool forTextEmphasis = false); 45 46 unsigned advance(int to, GlyphBuffer* = 0); 47 bool advanceOneCharacter(float& width); 48 49 float maxGlyphBoundingBoxY() const { ASSERT(m_accountForGlyphBounds); return m_maxGlyphBoundingBoxY; } 50 float minGlyphBoundingBoxY() const { ASSERT(m_accountForGlyphBounds); return m_minGlyphBoundingBoxY; } 51 float firstGlyphOverflow() const { ASSERT(m_accountForGlyphBounds); return m_firstGlyphOverflow; } 52 float lastGlyphOverflow() const { ASSERT(m_accountForGlyphBounds); return m_lastGlyphOverflow; } 53 54 const TextRun& run() const { return m_run; } 55 float runWidthSoFar() const { return m_runWidthSoFar; } 56 57 #if ENABLE(SVG_FONTS) 58 Vector<SVGGlyph::ArabicForm>& arabicForms() { return m_arabicForms; } 59 #endif 60 61 const Font* m_font; 62 63 const TextRun& m_run; 64 65 unsigned m_currentCharacter; 66 float m_runWidthSoFar; 67 float m_expansion; 68 float m_expansionPerOpportunity; 69 bool m_isAfterExpansion; 70 71 #if ENABLE(SVG_FONTS) 72 Vector<SVGGlyph::ArabicForm> m_arabicForms; 73 #endif 74 75 private: 76 struct CharacterData { 77 UChar32 character; 78 unsigned clusterLength; 79 int characterOffset; 80 }; 81 82 GlyphData glyphDataForCharacter(CharacterData&, bool normalizeSpace = false); 83 float characterWidth(UChar32, const GlyphData&) const; 84 void cacheFallbackFont(const SimpleFontData*, const SimpleFontData* primaryFont); 85 float adjustSpacing(float, const CharacterData&, const SimpleFontData&, GlyphBuffer*); 86 void updateGlyphBounds(const GlyphData&, float width, bool firstCharacter); 87 88 template <typename TextIterator> 89 unsigned advanceInternal(TextIterator&, GlyphBuffer*); 90 91 HashSet<const SimpleFontData*>* m_fallbackFonts; 92 float m_maxGlyphBoundingBoxY; 93 float m_minGlyphBoundingBoxY; 94 float m_firstGlyphOverflow; 95 float m_lastGlyphOverflow; 96 97 bool m_accountForGlyphBounds : 1; 98 bool m_forTextEmphasis : 1; 99 }; 100 101 } // namespace blink 102 103 #endif 104