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
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.
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.
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.
28 #include "platform/PlatformExport.h"
29 #include "platform/fonts/FontDescription.h"
30 #include "platform/fonts/FontFallbackList.h"
31 #include "platform/fonts/SimpleFontData.h"
32 #include "platform/fonts/TypesettingFeatures.h"
33 #include "platform/text/TextDirection.h"
34 #include "platform/text/TextPath.h"
35 #include "wtf/HashMap.h"
36 #include "wtf/HashSet.h"
37 #include "wtf/MathExtras.h"
38 #include "wtf/unicode/CharacterNames.h"
40 // "X11/X.h" defines Complex to 0 and conflicts
41 // with Complex value in CodePath enum.
52 class FontPlatformData;
55 class GraphicsContext;
57 struct TextRunPaintInfo;
61 struct GlyphOverflow {
67 , computeBounds(false)
79 class PLATFORM_EXPORT Font {
82 Font(const FontDescription&, float letterSpacing, float wordSpacing);
86 Font& operator=(const Font&);
88 bool operator==(const Font& other) const;
89 bool operator!=(const Font& other) const { return !(*this == other); }
91 const FontDescription& fontDescription() const { return m_fontDescription; }
93 int pixelSize() const { return fontDescription().computedPixelSize(); }
94 float size() const { return fontDescription().computedSize(); }
96 void update(PassRefPtr<FontSelector>) const;
98 enum CustomFontNotReadyAction { DoNotPaintIfFontNotReady, UseFallbackIfFontNotReady };
99 void drawText(GraphicsContext*, const TextRunPaintInfo&, const FloatPoint&, CustomFontNotReadyAction = DoNotPaintIfFontNotReady) const;
100 void drawEmphasisMarks(GraphicsContext*, const TextRunPaintInfo&, const AtomicString& mark, const FloatPoint&) const;
102 float width(const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, GlyphOverflow* = 0) const;
103 float width(const TextRun&, int& charsConsumed, String& glyphName) const;
105 int offsetForPosition(const TextRun&, float position, bool includePartialGlyphs) const;
106 FloatRect selectionRectForText(const TextRun&, const FloatPoint&, int h, int from = 0, int to = -1) const;
108 bool isSmallCaps() const { return m_fontDescription.smallCaps(); }
110 float wordSpacing() const { return m_wordSpacing; }
111 float letterSpacing() const { return m_letterSpacing; }
112 void setWordSpacing(float s) { m_wordSpacing = s; }
113 void setLetterSpacing(float s) { m_letterSpacing = s; }
114 bool isFixedPitch() const;
115 bool isPrinterFont() const { return m_fontDescription.usePrinterFont(); }
117 TypesettingFeatures typesettingFeatures() const { return static_cast<TypesettingFeatures>(m_typesettingFeatures); }
119 FontFamily& firstFamily() { return m_fontDescription.firstFamily(); }
120 const FontFamily& family() const { return m_fontDescription.family(); }
122 FontItalic italic() const { return m_fontDescription.italic(); }
123 FontWeight weight() const { return m_fontDescription.weight(); }
124 FontWidthVariant widthVariant() const { return m_fontDescription.widthVariant(); }
126 // Metrics that we query the FontFallbackList for.
127 const FontMetrics& fontMetrics() const { return primaryFont()->fontMetrics(); }
128 float spaceWidth() const { return primaryFont()->spaceWidth() + m_letterSpacing; }
129 float tabWidth(const SimpleFontData&, unsigned tabSize, float position) const;
130 float tabWidth(unsigned tabSize, float position) const { return tabWidth(*primaryFont(), tabSize, position); }
132 int emphasisMarkAscent(const AtomicString&) const;
133 int emphasisMarkDescent(const AtomicString&) const;
134 int emphasisMarkHeight(const AtomicString&) const;
136 const SimpleFontData* primaryFont() const;
137 const FontData* fontDataAt(unsigned) const;
138 inline GlyphData glyphDataForCharacter(UChar32 c, bool mirror, FontDataVariant variant = AutoVariant) const
140 return glyphDataAndPageForCharacter(c, mirror, variant).first;
143 const SimpleFontData* fontDataForCombiningCharacterSequence(const UChar*, size_t length, FontDataVariant) const;
145 std::pair<GlyphData, GlyphPage*> glyphDataAndPageForCharacter(UChar32, bool mirror, FontDataVariant = AutoVariant) const;
146 bool primaryFontHasGlyphForCharacter(UChar32) const;
148 static bool isCJKIdeograph(UChar32);
149 static bool isCJKIdeographOrSymbol(UChar32);
151 static unsigned expansionOpportunityCount(const LChar*, size_t length, TextDirection, bool& isAfterExpansion);
152 static unsigned expansionOpportunityCount(const UChar*, size_t length, TextDirection, bool& isAfterExpansion);
154 static void setShouldUseSmoothing(bool);
155 static bool shouldUseSmoothing();
157 CodePath codePath(const TextRun&) const;
158 static CodePath characterRangeCodePath(const LChar*, unsigned) { return SimplePath; }
159 static CodePath characterRangeCodePath(const UChar*, unsigned len);
162 enum ForTextEmphasisOrNot { NotForTextEmphasis, ForTextEmphasis };
164 // Returns the initial in-stream advance.
165 float getGlyphsAndAdvancesForSimpleText(const TextRun&, int from, int to, GlyphBuffer&, ForTextEmphasisOrNot = NotForTextEmphasis) const;
166 void drawSimpleText(GraphicsContext*, const TextRunPaintInfo&, const FloatPoint&) const;
167 void drawEmphasisMarksForSimpleText(GraphicsContext*, const TextRunPaintInfo&, const AtomicString& mark, const FloatPoint&) const;
168 void drawGlyphs(GraphicsContext*, const SimpleFontData*, const GlyphBuffer&, unsigned from, unsigned numGlyphs, const FloatPoint&, const FloatRect& textRect) const;
169 void drawGlyphBuffer(GraphicsContext*, const TextRunPaintInfo&, const GlyphBuffer&, const FloatPoint&) const;
170 void drawEmphasisMarks(GraphicsContext*, const TextRunPaintInfo&, const GlyphBuffer&, const AtomicString&, const FloatPoint&) const;
171 float floatWidthForSimpleText(const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, GlyphOverflow* = 0) const;
172 int offsetForPositionForSimpleText(const TextRun&, float position, bool includePartialGlyphs) const;
173 FloatRect selectionRectForSimpleText(const TextRun&, const FloatPoint&, int h, int from, int to) const;
175 bool getEmphasisMarkGlyphData(const AtomicString&, GlyphData&) const;
177 static bool canReturnFallbackFontsForComplexText();
178 static bool canExpandAroundIdeographsInComplexText();
180 // Returns the initial in-stream advance.
181 float getGlyphsAndAdvancesForComplexText(const TextRun&, int from, int to, GlyphBuffer&, ForTextEmphasisOrNot = NotForTextEmphasis) const;
182 void drawComplexText(GraphicsContext*, const TextRunPaintInfo&, const FloatPoint&) const;
183 void drawEmphasisMarksForComplexText(GraphicsContext*, const TextRunPaintInfo&, const AtomicString& mark, const FloatPoint&) const;
184 float floatWidthForComplexText(const TextRun&, HashSet<const SimpleFontData*>* fallbackFonts = 0, GlyphOverflow* = 0) const;
185 int offsetForPositionForComplexText(const TextRun&, float position, bool includePartialGlyphs) const;
186 FloatRect selectionRectForComplexText(const TextRun&, const FloatPoint&, int h, int from, int to) const;
188 friend struct WidthIterator;
189 friend class SVGTextRunRenderingContext;
192 // Useful for debugging the different font rendering code paths.
193 static void setCodePath(CodePath);
194 static CodePath codePath();
195 static CodePath s_codePath;
197 static void setDefaultTypesettingFeatures(TypesettingFeatures);
198 static TypesettingFeatures defaultTypesettingFeatures();
200 static const uint8_t s_roundingHackCharacterTable[256];
201 static bool isRoundingHackCharacter(UChar32 c)
203 return !(c & ~0xFF) && s_roundingHackCharacterTable[c];
206 FontSelector* fontSelector() const;
207 static bool treatAsSpace(UChar c) { return c == ' ' || c == '\t' || c == '\n' || c == noBreakSpace; }
208 static bool treatAsZeroWidthSpace(UChar c) { return treatAsZeroWidthSpaceInComplexScript(c) || c == 0x200c || c == 0x200d; }
209 static bool treatAsZeroWidthSpaceInComplexScript(UChar c) { return c < 0x20 || (c >= 0x7F && c < 0xA0) || c == softHyphen || c == zeroWidthSpace || (c >= 0x200e && c <= 0x200f) || (c >= 0x202a && c <= 0x202e) || c == zeroWidthNoBreakSpace || c == objectReplacementCharacter; }
210 static bool canReceiveTextEmphasis(UChar32 c);
212 static inline UChar normalizeSpaces(UChar character)
214 if (treatAsSpace(character))
217 if (treatAsZeroWidthSpace(character))
218 return zeroWidthSpace;
223 static String normalizeSpaces(const LChar*, unsigned length);
224 static String normalizeSpaces(const UChar*, unsigned length);
226 FontFallbackList* fontList() const { return m_fontFallbackList.get(); }
228 void willUseFontData() const;
231 bool loadingCustomFonts() const
233 return m_fontFallbackList && m_fontFallbackList->loadingCustomFonts();
236 TypesettingFeatures computeTypesettingFeatures() const
238 TextRenderingMode textRenderingMode = m_fontDescription.textRenderingMode();
239 TypesettingFeatures features = s_defaultTypesettingFeatures;
241 switch (textRenderingMode) {
242 case AutoTextRendering:
245 features &= ~(Kerning | Ligatures);
247 case GeometricPrecision:
248 case OptimizeLegibility:
249 features |= Kerning | Ligatures;
253 switch (m_fontDescription.kerning()) {
254 case FontDescription::NoneKerning:
255 features &= ~Kerning;
257 case FontDescription::NormalKerning:
260 case FontDescription::AutoKerning:
264 switch (m_fontDescription.commonLigaturesState()) {
265 case FontDescription::DisabledLigaturesState:
266 features &= ~Ligatures;
268 case FontDescription::EnabledLigaturesState:
269 features |= Ligatures;
271 case FontDescription::NormalLigaturesState:
278 static TypesettingFeatures s_defaultTypesettingFeatures;
280 FontDescription m_fontDescription;
281 mutable RefPtr<FontFallbackList> m_fontFallbackList;
282 float m_letterSpacing;
284 mutable unsigned m_typesettingFeatures : 2; // (TypesettingFeatures) Caches values computed from m_fontDescription.
291 inline const SimpleFontData* Font::primaryFont() const
293 ASSERT(m_fontFallbackList);
294 return m_fontFallbackList->primarySimpleFontData(m_fontDescription);
297 inline const FontData* Font::fontDataAt(unsigned index) const
299 ASSERT(m_fontFallbackList);
300 return m_fontFallbackList->fontDataAt(m_fontDescription, index);
303 inline bool Font::isFixedPitch() const
305 ASSERT(m_fontFallbackList);
306 return m_fontFallbackList->isFixedPitch(m_fontDescription);
309 inline FontSelector* Font::fontSelector() const
311 return m_fontFallbackList ? m_fontFallbackList->fontSelector() : 0;
314 inline float Font::tabWidth(const SimpleFontData& fontData, unsigned tabSize, float position) const
317 return letterSpacing();
318 float tabWidth = tabSize * fontData.spaceWidth() + letterSpacing();
319 return tabWidth - fmodf(position, tabWidth);