1 /*
2 * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
3 * (C) 2000 Antti Koivisto (koivisto@kde.org)
4 * (C) 2000 Dirk Mueller (mueller@kde.org)
5 * Copyright (C) 2003, 2006, 2007, 2010, 2011 Apple Inc. All rights reserved.
6 * Copyright (C) 2008 Holger Hans Peter Freyther
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
17 *
18 * You should have received a copy of the GNU Library General Public License
19 * along with this library; see the file COPYING.LIB. If not, write to
20 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
22 *
23 */
24
25 #ifndef Font_h
26 #define Font_h
27
28 #include "FontDescription.h"
29 #include "FontFallbackList.h"
30 #include "SimpleFontData.h"
31 #include "TextDirection.h"
32 #include "TypesettingFeatures.h"
33 #include <wtf/HashMap.h>
34 #include <wtf/HashSet.h>
35 #include <wtf/MathExtras.h>
36 #include <wtf/unicode/CharacterNames.h>
37
38 #if PLATFORM(QT)
39 #include <QFont>
40 #endif
41
42 namespace WebCore {
43
44 class FloatPoint;
45 class FloatRect;
46 class FontData;
47 class FontMetrics;
48 class FontPlatformData;
49 class FontSelector;
50 class GlyphBuffer;
51 class GlyphPageTreeNode;
52 class GraphicsContext;
53 class SVGFontElement;
54 class TextRun;
55
56 struct GlyphData;
57
58 struct GlyphOverflow {
GlyphOverflowGlyphOverflow59 GlyphOverflow()
60 : left(0)
61 , right(0)
62 , top(0)
63 , bottom(0)
64 , computeBounds(false)
65 {
66 }
67
68 int left;
69 int right;
70 int top;
71 int bottom;
72 bool computeBounds;
73 };
74
75
76 class Font {
77 public:
78 Font();
79 Font(const FontDescription&, short letterSpacing, short wordSpacing);
80 // This constructor is only used if the platform wants to start with a native font.
81 Font(const FontPlatformData&, bool isPrinting, FontSmoothingMode = AutoSmoothing);
82 ~Font();
83
84 Font(const Font&);
85 Font& operator=(const Font&);
86
87 bool operator==(const Font& other) const;
88 bool operator!=(const Font& other) const { return !(*this == other); }
89
fontDescription()90 const FontDescription& fontDescription() const { return m_fontDescription; }
91
pixelSize()92 int pixelSize() const { return fontDescription().computedPixelSize(); }
size()93 float size() const { return fontDescription().computedSize(); }
94
95 void update(PassRefPtr<FontSelector>) const;
96
97 void drawText(GraphicsContext*, const TextRun&, const FloatPoint&, int from = 0, int to = -1) const;
98 void drawEmphasisMarks(GraphicsContext*, const TextRun&, const AtomicString& mark, const FloatPoint&, int from = 0, int to = -1) const;
99
100 float width(const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, GlyphOverflow* = 0) const;
101 float width(const TextRun&, int extraCharsAvailable, int& charsConsumed, String& glyphName) const;
102
103 int offsetForPosition(const TextRun&, float position, bool includePartialGlyphs) const;
104 FloatRect selectionRectForText(const TextRun&, const FloatPoint&, int h, int from = 0, int to = -1) const;
105
isSmallCaps()106 bool isSmallCaps() const { return m_fontDescription.smallCaps(); }
107
wordSpacing()108 short wordSpacing() const { return m_wordSpacing; }
letterSpacing()109 short letterSpacing() const { return m_letterSpacing; }
setWordSpacing(short s)110 void setWordSpacing(short s) { m_wordSpacing = s; }
setLetterSpacing(short s)111 void setLetterSpacing(short s) { m_letterSpacing = s; }
112 bool isFixedPitch() const;
isPrinterFont()113 bool isPrinterFont() const { return m_fontDescription.usePrinterFont(); }
114
renderingMode()115 FontRenderingMode renderingMode() const { return m_fontDescription.renderingMode(); }
116
typesettingFeatures()117 TypesettingFeatures typesettingFeatures() const
118 {
119 TextRenderingMode textRenderingMode = m_fontDescription.textRenderingMode();
120 return textRenderingMode == OptimizeLegibility || textRenderingMode == GeometricPrecision ? Kerning | Ligatures : 0;
121 }
122
firstFamily()123 FontFamily& firstFamily() { return m_fontDescription.firstFamily(); }
family()124 const FontFamily& family() const { return m_fontDescription.family(); }
125
italic()126 bool italic() const { return m_fontDescription.italic(); }
weight()127 FontWeight weight() const { return m_fontDescription.weight(); }
widthVariant()128 FontWidthVariant widthVariant() const { return m_fontDescription.widthVariant(); }
129
isPlatformFont()130 bool isPlatformFont() const { return m_isPlatformFont; }
131
132 // Metrics that we query the FontFallbackList for.
fontMetrics()133 const FontMetrics& fontMetrics() const { return primaryFont()->fontMetrics(); }
spaceWidth()134 float spaceWidth() const { return primaryFont()->spaceWidth() + m_letterSpacing; }
tabWidth(const SimpleFontData & fontData)135 float tabWidth(const SimpleFontData& fontData) const { return 8 * fontData.spaceWidth() + letterSpacing(); }
136 int emphasisMarkAscent(const AtomicString&) const;
137 int emphasisMarkDescent(const AtomicString&) const;
138 int emphasisMarkHeight(const AtomicString&) const;
139
140 const SimpleFontData* primaryFont() const;
141 const FontData* fontDataAt(unsigned) const;
142 GlyphData glyphDataForCharacter(UChar32, bool mirror, FontDataVariant = AutoVariant) const;
143 bool primaryFontHasGlyphForCharacter(UChar32) const;
144
145 static bool isCJKIdeograph(UChar32);
146 static bool isCJKIdeographOrSymbol(UChar32);
147
148 static unsigned expansionOpportunityCount(const UChar*, size_t length, TextDirection, bool& isAfterExpansion);
149
150 #if PLATFORM(QT)
151 QFont font() const;
152 #endif
153
154 static void setShouldUseSmoothing(bool);
155 static bool shouldUseSmoothing();
156
157 enum CodePath { Auto, Simple, Complex, SimpleWithGlyphOverflow };
158
159 private:
160 #if ENABLE(SVG_FONTS)
161 void drawTextUsingSVGFont(GraphicsContext*, const TextRun&, const FloatPoint&, int from, int to) const;
162 float floatWidthUsingSVGFont(const TextRun&) const;
163 float floatWidthUsingSVGFont(const TextRun&, int extraCharsAvailable, int& charsConsumed, String& glyphName) const;
164 FloatRect selectionRectForTextUsingSVGFont(const TextRun&, const FloatPoint&, int h, int from, int to) const;
165 int offsetForPositionForTextUsingSVGFont(const TextRun&, float position, bool includePartialGlyphs) const;
166 #endif
167
168 enum ForTextEmphasisOrNot { NotForTextEmphasis, ForTextEmphasis };
169
170 // Returns the initial in-stream advance.
171 float getGlyphsAndAdvancesForSimpleText(const TextRun&, int from, int to, GlyphBuffer&, ForTextEmphasisOrNot = NotForTextEmphasis) const;
172 void drawSimpleText(GraphicsContext*, const TextRun&, const FloatPoint&, int from, int to) const;
173 void drawEmphasisMarksForSimpleText(GraphicsContext*, const TextRun&, const AtomicString& mark, const FloatPoint&, int from, int to) const;
174 void drawGlyphs(GraphicsContext*, const SimpleFontData*, const GlyphBuffer&, int from, int to, const FloatPoint&) const;
175 void drawGlyphBuffer(GraphicsContext*, const GlyphBuffer&, const FloatPoint&) const;
176 void drawEmphasisMarks(GraphicsContext* context, const GlyphBuffer&, const AtomicString&, const FloatPoint&) const;
177 float floatWidthForSimpleText(const TextRun&, GlyphBuffer*, HashSet<const SimpleFontData*>* fallbackFonts = 0, GlyphOverflow* = 0) const;
178 int offsetForPositionForSimpleText(const TextRun&, float position, bool includePartialGlyphs) const;
179 FloatRect selectionRectForSimpleText(const TextRun&, const FloatPoint&, int h, int from, int to) const;
180
181 bool getEmphasisMarkGlyphData(const AtomicString&, GlyphData&) const;
182
183 static bool canReturnFallbackFontsForComplexText();
184 static bool canExpandAroundIdeographsInComplexText();
185
186 CodePath codePath(const TextRun&) const;
187
188 // Returns the initial in-stream advance.
189 float getGlyphsAndAdvancesForComplexText(const TextRun&, int from, int to, GlyphBuffer&, ForTextEmphasisOrNot = NotForTextEmphasis) const;
190 void drawComplexText(GraphicsContext*, const TextRun&, const FloatPoint&, int from, int to) const;
191 void drawEmphasisMarksForComplexText(GraphicsContext*, const TextRun&, const AtomicString& mark, const FloatPoint&, int from, int to) const;
192 float floatWidthForComplexText(const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, GlyphOverflow* = 0) const;
193 int offsetForPositionForComplexText(const TextRun&, float position, bool includePartialGlyphs) const;
194 FloatRect selectionRectForComplexText(const TextRun&, const FloatPoint&, int h, int from, int to) const;
195
196 friend struct WidthIterator;
197
198 public:
199 // Useful for debugging the different font rendering code paths.
200 static void setCodePath(CodePath);
201 static CodePath codePath();
202 static CodePath s_codePath;
203
204 FontSelector* fontSelector() const;
treatAsSpace(UChar c)205 static bool treatAsSpace(UChar c) { return c == ' ' || c == '\t' || c == '\n' || c == noBreakSpace; }
treatAsZeroWidthSpace(UChar c)206 static bool treatAsZeroWidthSpace(UChar c) { return treatAsZeroWidthSpaceInComplexScript(c) || c == 0x200c || c == 0x200d; }
treatAsZeroWidthSpaceInComplexScript(UChar c)207 static bool treatAsZeroWidthSpaceInComplexScript(UChar c) { return c < 0x20 || (c >= 0x7F && c < 0xA0) || c == softHyphen || (c >= 0x200e && c <= 0x200f) || (c >= 0x202a && c <= 0x202e) || c == zeroWidthNoBreakSpace || c == objectReplacementCharacter; }
208 static bool canReceiveTextEmphasis(UChar32 c);
209
normalizeSpaces(UChar character)210 static inline UChar normalizeSpaces(UChar character)
211 {
212 if (treatAsSpace(character))
213 return space;
214
215 if (treatAsZeroWidthSpace(character))
216 return zeroWidthSpace;
217
218 return character;
219 }
220
221 static String normalizeSpaces(const UChar*, unsigned length);
222
223 #if ENABLE(SVG_FONTS)
224 bool isSVGFont() const;
225 SVGFontElement* svgFont() const;
226 #endif
227
needsTranscoding()228 bool needsTranscoding() const { return m_needsTranscoding; }
229
230 private:
loadingCustomFonts()231 bool loadingCustomFonts() const
232 {
233 return m_fontList && m_fontList->loadingCustomFonts();
234 }
235
236 FontDescription m_fontDescription;
237 mutable RefPtr<FontFallbackList> m_fontList;
238 short m_letterSpacing;
239 short m_wordSpacing;
240 bool m_isPlatformFont;
241 bool m_needsTranscoding;
242 };
243
~Font()244 inline Font::~Font()
245 {
246 }
247
primaryFont()248 inline const SimpleFontData* Font::primaryFont() const
249 {
250 ASSERT(m_fontList);
251 return m_fontList->primarySimpleFontData(this);
252 }
253
fontDataAt(unsigned index)254 inline const FontData* Font::fontDataAt(unsigned index) const
255 {
256 ASSERT(m_fontList);
257 return m_fontList->fontDataAt(this, index);
258 }
259
isFixedPitch()260 inline bool Font::isFixedPitch() const
261 {
262 ASSERT(m_fontList);
263 return m_fontList->isFixedPitch(this);
264 }
265
fontSelector()266 inline FontSelector* Font::fontSelector() const
267 {
268 return m_fontList ? m_fontList->fontSelector() : 0;
269 }
270
271 }
272
273 #endif
274