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, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
6 * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
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.LIother.m_  If not, write to
20 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 * Boston, MA 02110-1301, USm_
22 *
23 */
24
25#ifndef FontDescription_h
26#define FontDescription_h
27
28#include "platform/FontFamilyNames.h"
29#include "platform/fonts/FixedPitchFontType.h"
30#include "platform/fonts/FontCacheKey.h"
31#include "platform/fonts/FontFamily.h"
32#include "platform/fonts/FontFeatureSettings.h"
33#include "platform/fonts/FontOrientation.h"
34#include "platform/fonts/FontSmoothingMode.h"
35#include "platform/fonts/FontTraits.h"
36#include "platform/fonts/FontWidthVariant.h"
37#include "platform/fonts/TextRenderingMode.h"
38#include "platform/fonts/TypesettingFeatures.h"
39#include "platform/text/NonCJKGlyphOrientation.h"
40#include "wtf/MathExtras.h"
41
42#include "wtf/RefPtr.h"
43
44#include <unicode/uscript.h>
45
46namespace blink {
47
48class PLATFORM_EXPORT FontDescription {
49public:
50    enum GenericFamilyType { NoFamily, StandardFamily, SerifFamily, SansSerifFamily,
51                             MonospaceFamily, CursiveFamily, FantasyFamily, PictographFamily };
52
53    enum Kerning { AutoKerning, NormalKerning, NoneKerning };
54
55    enum LigaturesState { NormalLigaturesState, DisabledLigaturesState, EnabledLigaturesState };
56
57    FontDescription()
58        : m_locale("en")
59        , m_specifiedSize(0)
60        , m_computedSize(0)
61        , m_letterSpacing(0)
62        , m_wordSpacing(0)
63        , m_orientation(Horizontal)
64        , m_nonCJKGlyphOrientation(NonCJKGlyphOrientationVerticalRight)
65        , m_widthVariant(RegularWidth)
66        , m_style(FontStyleNormal)
67        , m_variant(FontVariantNormal)
68        , m_isAbsoluteSize(false)
69        , m_weight(FontWeightNormal)
70        , m_stretch(FontStretchNormal)
71        , m_genericFamily(NoFamily)
72        , m_kerning(AutoKerning)
73        , m_commonLigaturesState(NormalLigaturesState)
74        , m_discretionaryLigaturesState(NormalLigaturesState)
75        , m_historicalLigaturesState(NormalLigaturesState)
76        , m_contextualLigaturesState(NormalLigaturesState)
77        , m_keywordSize(0)
78        , m_fontSmoothing(AutoSmoothing)
79        , m_textRendering(AutoTextRendering)
80        , m_script(USCRIPT_COMMON)
81        , m_syntheticBold(false)
82        , m_syntheticItalic(false)
83        , m_subpixelTextPosition(s_useSubpixelTextPositioning)
84        , m_typesettingFeatures(s_defaultTypesettingFeatures)
85    {
86    }
87
88    bool operator==(const FontDescription&) const;
89    bool operator!=(const FontDescription& other) const { return !(*this == other); }
90
91    struct VariantLigatures {
92        VariantLigatures()
93            : common(NormalLigaturesState)
94            , discretionary(NormalLigaturesState)
95            , historical(NormalLigaturesState)
96            , contextual(NormalLigaturesState)
97        {
98        }
99
100        unsigned common : 2;
101        unsigned discretionary : 2;
102        unsigned historical : 2;
103        unsigned contextual : 2;
104    };
105
106    struct Size {
107        Size(unsigned keyword, float value, bool isAbsolute)
108            : keyword(keyword)
109            , isAbsolute(isAbsolute)
110            , value(value)
111        {
112        }
113        unsigned keyword : 4; // FontDescription::keywordSize
114        unsigned isAbsolute : 1; // FontDescription::isAbsoluteSize
115        float value;
116    };
117
118    const FontFamily& family() const { return m_familyList; }
119    FontFamily& firstFamily() { return m_familyList; }
120    Size size() const { return Size(m_keywordSize, m_specifiedSize, m_isAbsoluteSize); }
121    float specifiedSize() const { return m_specifiedSize; }
122    float computedSize() const { return m_computedSize; }
123    FontStyle style() const { return static_cast<FontStyle>(m_style); }
124    int computedPixelSize() const { return int(m_computedSize + 0.5f); }
125    FontVariant variant() const { return static_cast<FontVariant>(m_variant); }
126    bool isAbsoluteSize() const { return m_isAbsoluteSize; }
127    FontWeight weight() const { return static_cast<FontWeight>(m_weight); }
128    FontStretch stretch() const { return static_cast<FontStretch>(m_stretch); }
129    static FontWeight lighterWeight(FontWeight);
130    static FontWeight bolderWeight(FontWeight);
131    static Size largerSize(const Size&);
132    static Size smallerSize(const Size&);
133    GenericFamilyType genericFamily() const { return static_cast<GenericFamilyType>(m_genericFamily); }
134
135    // only use fixed default size when there is only one font family, and that family is "monospace"
136    FixedPitchFontType fixedPitchFontType() const
137    {
138        if (genericFamily() == MonospaceFamily && !family().next() && family().family() == FontFamilyNames::webkit_monospace)
139            return FixedPitchFont;
140        return NonFixedPitchFont;
141    }
142    Kerning kerning() const { return static_cast<Kerning>(m_kerning); }
143    VariantLigatures variantLigatures() const;
144    LigaturesState commonLigaturesState() const { return static_cast<LigaturesState>(m_commonLigaturesState); }
145    LigaturesState discretionaryLigaturesState() const { return static_cast<LigaturesState>(m_discretionaryLigaturesState); }
146    LigaturesState historicalLigaturesState() const { return static_cast<LigaturesState>(m_historicalLigaturesState); }
147    LigaturesState contextualLigaturesState() const { return static_cast<LigaturesState>(m_contextualLigaturesState); }
148    unsigned keywordSize() const { return m_keywordSize; }
149    FontSmoothingMode fontSmoothing() const { return static_cast<FontSmoothingMode>(m_fontSmoothing); }
150    TextRenderingMode textRendering() const { return static_cast<TextRenderingMode>(m_textRendering); }
151    UScriptCode script() const { return static_cast<UScriptCode>(m_script); }
152    const String& locale() const { return m_locale; }
153    bool isSyntheticBold() const { return m_syntheticBold; }
154    bool isSyntheticItalic() const { return m_syntheticItalic; }
155    bool useSubpixelPositioning() const { return m_subpixelTextPosition; }
156
157    FontTraits traits() const;
158    float wordSpacing() const { return m_wordSpacing; }
159    float letterSpacing() const { return m_letterSpacing; }
160    FontOrientation orientation() const { return static_cast<FontOrientation>(m_orientation); }
161    NonCJKGlyphOrientation nonCJKGlyphOrientation() const { return static_cast<NonCJKGlyphOrientation>(m_nonCJKGlyphOrientation); }
162    FontWidthVariant widthVariant() const { return static_cast<FontWidthVariant>(m_widthVariant); }
163    FontFeatureSettings* featureSettings() const { return m_featureSettings.get(); }
164
165    float effectiveFontSize() const; // Returns either the computedSize or the computedPixelSize
166    FontCacheKey cacheKey(const FontFaceCreationParams&, FontTraits desiredTraits = FontTraits(0)) const;
167
168    void setFamily(const FontFamily& family) { m_familyList = family; }
169    void setComputedSize(float s) { m_computedSize = clampToFloat(s); }
170    void setSpecifiedSize(float s) { m_specifiedSize = clampToFloat(s); }
171    void setStyle(FontStyle i) { m_style = i; }
172    void setVariant(FontVariant c) { m_variant = c; }
173    void setVariantLigatures(const VariantLigatures&);
174    void setIsAbsoluteSize(bool s) { m_isAbsoluteSize = s; }
175    void setWeight(FontWeight w) { m_weight = w; }
176    void setStretch(FontStretch s) { m_stretch = s; }
177    void setGenericFamily(GenericFamilyType genericFamily) { m_genericFamily = genericFamily; }
178    void setKerning(Kerning kerning) { m_kerning = kerning; updateTypesettingFeatures(); }
179    void setKeywordSize(unsigned s) { m_keywordSize = s; }
180    void setFontSmoothing(FontSmoothingMode smoothing) { m_fontSmoothing = smoothing; }
181    void setTextRendering(TextRenderingMode rendering) { m_textRendering = rendering; updateTypesettingFeatures(); }
182    void setOrientation(FontOrientation orientation) { m_orientation = orientation; }
183    void setNonCJKGlyphOrientation(NonCJKGlyphOrientation orientation) { m_nonCJKGlyphOrientation = orientation; }
184    void setWidthVariant(FontWidthVariant widthVariant) { m_widthVariant = widthVariant; }
185    void setScript(UScriptCode s) { m_script = s; }
186    void setLocale(const String& locale) { m_locale = locale; }
187    void setSyntheticBold(bool syntheticBold) { m_syntheticBold = syntheticBold; }
188    void setSyntheticItalic(bool syntheticItalic) { m_syntheticItalic = syntheticItalic; }
189    void setFeatureSettings(PassRefPtr<FontFeatureSettings> settings) { m_featureSettings = settings; }
190    void setTraits(FontTraits);
191    void setWordSpacing(float s) { m_wordSpacing = s; }
192    void setLetterSpacing(float s) { m_letterSpacing = s; }
193
194    TypesettingFeatures typesettingFeatures() const { return static_cast<TypesettingFeatures>(m_typesettingFeatures); }
195
196    static void setSubpixelPositioning(bool b) { s_useSubpixelTextPositioning = b; }
197    static bool subpixelPositioning() { return s_useSubpixelTextPositioning; }
198
199    static void setDefaultTypesettingFeatures(TypesettingFeatures);
200    static TypesettingFeatures defaultTypesettingFeatures();
201
202private:
203    FontFamily m_familyList; // The list of font families to be used.
204    RefPtr<FontFeatureSettings> m_featureSettings;
205    String m_locale;
206
207    void updateTypesettingFeatures() const;
208
209    float m_specifiedSize;   // Specified CSS value. Independent of rendering issues such as integer
210                             // rounding, minimum font sizes, and zooming.
211    float m_computedSize;    // Computed size adjusted for the minimum font size and the zoom factor.
212
213    float m_letterSpacing;
214    float m_wordSpacing;
215
216    unsigned m_orientation : 1; // FontOrientation - Whether the font is rendering on a horizontal line or a vertical line.
217    unsigned m_nonCJKGlyphOrientation : 1; // NonCJKGlyphOrientation - Only used by vertical text. Determines the default orientation for non-ideograph glyphs.
218
219    unsigned m_widthVariant : 2; // FontWidthVariant
220
221    unsigned m_style : 1; // FontStyle
222    unsigned m_variant : 1; // FontVariant
223    unsigned m_isAbsoluteSize : 1; // Whether or not CSS specified an explicit size
224                                  // (logical sizes like "medium" don't count).
225    unsigned m_weight : 4; // FontWeight
226    unsigned m_stretch : 4; // FontStretch
227    unsigned m_genericFamily : 3; // GenericFamilyType
228
229    unsigned m_kerning : 2; // Kerning
230
231    unsigned m_commonLigaturesState : 2;
232    unsigned m_discretionaryLigaturesState : 2;
233    unsigned m_historicalLigaturesState : 2;
234    unsigned m_contextualLigaturesState : 2;
235
236    unsigned m_keywordSize : 4; // We cache whether or not a font is currently represented by a CSS keyword (e.g., medium).  If so,
237                           // then we can accurately translate across different generic families to adjust for different preference settings
238                           // (e.g., 13px monospace vs. 16px everything else).  Sizes are 1-8 (like the HTML size values for <font>).
239
240    unsigned m_fontSmoothing : 2; // FontSmoothingMode
241    unsigned m_textRendering : 2; // TextRenderingMode
242    unsigned m_script : 7; // Used to help choose an appropriate font for generic font families.
243    unsigned m_syntheticBold : 1;
244    unsigned m_syntheticItalic : 1;
245    unsigned m_subpixelTextPosition : 1;
246
247    mutable unsigned m_typesettingFeatures : 2; // TypesettingFeatures
248
249    static TypesettingFeatures s_defaultTypesettingFeatures;
250
251    static bool s_useSubpixelTextPositioning;
252};
253
254inline bool FontDescription::operator==(const FontDescription& other) const
255{
256    return m_familyList == other.m_familyList
257        && m_specifiedSize == other.m_specifiedSize
258        && m_computedSize == other.m_computedSize
259        && m_letterSpacing == other.m_letterSpacing
260        && m_wordSpacing == other.m_wordSpacing
261        && m_style == other.m_style
262        && m_variant == other.m_variant
263        && m_isAbsoluteSize == other.m_isAbsoluteSize
264        && m_weight == other.m_weight
265        && m_stretch == other.m_stretch
266        && m_genericFamily == other.m_genericFamily
267        && m_kerning == other.m_kerning
268        && m_commonLigaturesState == other.m_commonLigaturesState
269        && m_discretionaryLigaturesState == other.m_discretionaryLigaturesState
270        && m_historicalLigaturesState == other.m_historicalLigaturesState
271        && m_contextualLigaturesState == other.m_contextualLigaturesState
272        && m_keywordSize == other.m_keywordSize
273        && m_fontSmoothing == other.m_fontSmoothing
274        && m_textRendering == other.m_textRendering
275        && m_orientation == other.m_orientation
276        && m_nonCJKGlyphOrientation == other.m_nonCJKGlyphOrientation
277        && m_widthVariant == other.m_widthVariant
278        && m_script == other.m_script
279        && m_syntheticBold == other.m_syntheticBold
280        && m_syntheticItalic == other.m_syntheticItalic
281        && m_featureSettings == other.m_featureSettings
282        && m_subpixelTextPosition == other.m_subpixelTextPosition;
283}
284
285} // namespace blink
286
287#endif
288