1 /*
2 * Copyright (C) Research In Motion Limited 2010. All rights reserved.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 #include "config.h"
21
22 #if ENABLE(SVG)
23 #include "SVGTextLayoutEngineSpacing.h"
24
25 #include "Font.h"
26 #include "SVGRenderStyle.h"
27
28 #if ENABLE(SVG_FONTS)
29 #include "SVGFontElement.h"
30 #endif
31
32 namespace WebCore {
33
SVGTextLayoutEngineSpacing(const Font & font)34 SVGTextLayoutEngineSpacing::SVGTextLayoutEngineSpacing(const Font& font)
35 : m_font(font)
36 , m_lastCharacter(0)
37 {
38 }
39
calculateSVGKerning(bool isVerticalText,const SVGTextMetrics::Glyph & currentGlyph)40 float SVGTextLayoutEngineSpacing::calculateSVGKerning(bool isVerticalText, const SVGTextMetrics::Glyph& currentGlyph)
41 {
42 #if ENABLE(SVG_FONTS)
43 if (!m_font.isSVGFont()) {
44 m_lastGlyph.isValid = false;
45 return 0;
46 }
47
48 SVGFontElement* svgFont = m_font.svgFont();
49 ASSERT(svgFont);
50
51 float kerning = 0;
52 if (m_lastGlyph.isValid) {
53 if (isVerticalText)
54 kerning = svgFont->verticalKerningForPairOfStringsAndGlyphs(m_lastGlyph.unicodeString, m_lastGlyph.name, currentGlyph.unicodeString, currentGlyph.name);
55 else
56 kerning = svgFont->horizontalKerningForPairOfStringsAndGlyphs(m_lastGlyph.unicodeString, m_lastGlyph.name, currentGlyph.unicodeString, currentGlyph.name);
57 }
58
59 m_lastGlyph = currentGlyph;
60 m_lastGlyph.isValid = true;
61 kerning *= m_font.size() / m_font.fontMetrics().unitsPerEm();
62 return kerning;
63 #else
64 UNUSED_PARAM(isVerticalText);
65 UNUSED_PARAM(currentGlyph);
66 return false;
67 #endif
68 }
69
calculateCSSKerningAndSpacing(const SVGRenderStyle * style,SVGElement * lengthContext,const UChar * currentCharacter)70 float SVGTextLayoutEngineSpacing::calculateCSSKerningAndSpacing(const SVGRenderStyle* style, SVGElement* lengthContext, const UChar* currentCharacter)
71 {
72 float kerning = 0;
73 SVGLength kerningLength = style->kerning();
74 if (kerningLength.unitType() == LengthTypePercentage)
75 kerning = kerningLength.valueAsPercentage() * m_font.pixelSize();
76 else
77 kerning = kerningLength.value(lengthContext);
78
79 const UChar* lastCharacter = m_lastCharacter;
80 m_lastCharacter = currentCharacter;
81
82 if (!kerning && !m_font.letterSpacing() && !m_font.wordSpacing())
83 return 0;
84
85 float spacing = m_font.letterSpacing() + kerning;
86 if (currentCharacter && lastCharacter && m_font.wordSpacing()) {
87 if (Font::treatAsSpace(*currentCharacter) && !Font::treatAsSpace(*lastCharacter))
88 spacing += m_font.wordSpacing();
89 }
90
91 return spacing;
92 }
93
94 }
95
96 #endif // ENABLE(SVG)
97