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
28namespace WebCore {
29
30class Font;
31class GlyphBuffer;
32class SimpleFontData;
33class TextRun;
34
35struct 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
41    float maxGlyphBoundingBoxY() const { ASSERT(m_accountForGlyphBounds); return m_maxGlyphBoundingBoxY; }
42    float minGlyphBoundingBoxY() const { ASSERT(m_accountForGlyphBounds); return m_minGlyphBoundingBoxY; }
43    float firstGlyphOverflow() const { ASSERT(m_accountForGlyphBounds); return m_firstGlyphOverflow; }
44    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
57private:
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