1 /*
2 * Copyright (C) 2006 Apple Computer, Inc. All rights reserved.
3 * Copyright (C) 2006 Michael Emmel mike.emmel@gmail.com
4 * Copyright (C) 2007, 2008 Alp Toker <alp@atoker.com>
5 * Copyright (C) 2007 Holger Hans Peter Freyther
6 * Copyright (C) 2007 Pioneer Research Center USA, Inc.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
19 * its contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
23 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
26 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
27 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
29 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 #include "config.h"
35 #include "SimpleFontData.h"
36
37 #include "FloatRect.h"
38 #include "Font.h"
39 #include "FontCache.h"
40 #include "FontDescription.h"
41 #include "GlyphBuffer.h"
42 #include <cairo.h>
43 #include <wtf/MathExtras.h>
44
45 namespace WebCore {
46
platformInit()47 void SimpleFontData::platformInit()
48 {
49 cairo_font_extents_t font_extents;
50 cairo_text_extents_t text_extents;
51 cairo_scaled_font_extents(m_platformData.m_scaledFont, &font_extents);
52 m_ascent = static_cast<int>(lroundf(font_extents.ascent));
53 m_descent = static_cast<int>(lroundf(font_extents.descent));
54 m_lineSpacing = static_cast<int>(lroundf(font_extents.height));
55 // There seems to be some rounding error in cairo (or in how we
56 // use cairo) with some fonts, like DejaVu Sans Mono, which makes
57 // cairo report a height smaller than ascent + descent, which is
58 // wrong and confuses WebCore's layout system. Workaround this
59 // while we figure out what's going on.
60 if (m_lineSpacing < m_ascent + m_descent)
61 m_lineSpacing = m_ascent + m_descent;
62 cairo_scaled_font_text_extents(m_platformData.m_scaledFont, "x", &text_extents);
63 m_xHeight = text_extents.height;
64 cairo_scaled_font_text_extents(m_platformData.m_scaledFont, " ", &text_extents);
65 m_spaceWidth = static_cast<float>(text_extents.x_advance);
66 m_lineGap = m_lineSpacing - m_ascent - m_descent;
67 m_syntheticBoldOffset = m_platformData.syntheticBold() ? 1.0f : 0.f;
68 }
69
platformCharWidthInit()70 void SimpleFontData::platformCharWidthInit()
71 {
72 m_avgCharWidth = 0.f;
73 m_maxCharWidth = 0.f;
74 initCharWidths();
75 }
76
platformDestroy()77 void SimpleFontData::platformDestroy()
78 {
79 delete m_smallCapsFontData;
80 m_smallCapsFontData = 0;
81 }
82
smallCapsFontData(const FontDescription & fontDescription) const83 SimpleFontData* SimpleFontData::smallCapsFontData(const FontDescription& fontDescription) const
84 {
85 if (!m_smallCapsFontData) {
86 FontDescription desc = FontDescription(fontDescription);
87 desc.setSpecifiedSize(0.70f*fontDescription.computedSize());
88 const FontPlatformData* pdata = new FontPlatformData(desc, desc.family().family());
89 m_smallCapsFontData = new SimpleFontData(*pdata);
90 }
91 return m_smallCapsFontData;
92 }
93
containsCharacters(const UChar * characters,int length) const94 bool SimpleFontData::containsCharacters(const UChar* characters, int length) const
95 {
96 bool result = true;
97
98 PangoCoverage* coverage = pango_font_get_coverage(m_platformData.m_font, pango_language_get_default());
99
100 for (int i = 0; i < length; i++) {
101 if (PANGO_COVERAGE_NONE == pango_coverage_get(coverage, characters[i])) {
102 result = false;
103 break;
104 }
105 }
106
107 pango_coverage_unref(coverage);
108
109 return result;
110 }
111
determinePitch()112 void SimpleFontData::determinePitch()
113 {
114 if (isCustomFont()) {
115 m_treatAsFixedPitch = false;
116 return;
117 }
118
119 m_treatAsFixedPitch = m_platformData.isFixedPitch();
120 }
121
platformWidthForGlyph(Glyph glyph) const122 float SimpleFontData::platformWidthForGlyph(Glyph glyph) const
123 {
124 ASSERT(m_platformData.m_scaledFont);
125
126 cairo_glyph_t cglyph = { glyph, 0, 0 };
127 cairo_text_extents_t extents;
128 cairo_scaled_font_glyph_extents(m_platformData.m_scaledFont, &cglyph, 1, &extents);
129
130 float w = (float)m_spaceWidth;
131 if (cairo_scaled_font_status(m_platformData.m_scaledFont) == CAIRO_STATUS_SUCCESS && extents.x_advance != 0)
132 w = (float)extents.x_advance;
133 return w;
134 }
135
136 }
137