1 /*
2  * Copyright (C) 2003, 2006, 2008, 2011 Apple Inc. All rights reserved.
3  * Copyright (C) 2008 Holger Hans Peter Freyther
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Library General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Library General Public License for more details.
14  *
15  * You should have received a copy of the GNU Library General Public License
16  * along with this library; see the file COPYING.LIB.  If not, write to
17  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18  * Boston, MA 02110-1301, USA.
19  *
20  */
21 
22 #ifndef WidthIterator_h
23 #define WidthIterator_h
24 
25 #include <wtf/HashSet.h>
26 #include <wtf/unicode/Unicode.h>
27 
28 namespace WebCore {
29 
30 class Font;
31 class GlyphBuffer;
32 class SimpleFontData;
33 class TextRun;
34 
35 struct WidthIterator {
36     WidthIterator(const Font*, const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, bool accountForGlyphBounds = false, bool forTextEmphasis = false);
37 
38     void advance(int to, GlyphBuffer* = 0);
39     bool advanceOneCharacter(float& width, GlyphBuffer* = 0);
40 
maxGlyphBoundingBoxYWidthIterator41     float maxGlyphBoundingBoxY() const { ASSERT(m_accountForGlyphBounds); return m_maxGlyphBoundingBoxY; }
minGlyphBoundingBoxYWidthIterator42     float minGlyphBoundingBoxY() const { ASSERT(m_accountForGlyphBounds); return m_minGlyphBoundingBoxY; }
firstGlyphOverflowWidthIterator43     float firstGlyphOverflow() const { ASSERT(m_accountForGlyphBounds); return m_firstGlyphOverflow; }
lastGlyphOverflowWidthIterator44     float lastGlyphOverflow() const { ASSERT(m_accountForGlyphBounds); return m_lastGlyphOverflow; }
45 
46     const Font* m_font;
47 
48     const TextRun& m_run;
49     int m_end;
50 
51     unsigned m_currentCharacter;
52     float m_runWidthSoFar;
53     float m_expansion;
54     float m_expansionPerOpportunity;
55     bool m_isAfterExpansion;
56 
57 private:
58     UChar32 normalizeVoicingMarks(int currentCharacter);
59 
60     HashSet<const SimpleFontData*>* m_fallbackFonts;
61     bool m_accountForGlyphBounds;
62     float m_maxGlyphBoundingBoxY;
63     float m_minGlyphBoundingBoxY;
64     float m_firstGlyphOverflow;
65     float m_lastGlyphOverflow;
66     bool m_forTextEmphasis;
67 };
68 
69 }
70 
71 #endif
72