FontDescription.h   [plain text]

/*
 * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
 *           (C) 2000 Antti Koivisto (koivisto@kde.org)
 *           (C) 2000 Dirk Mueller (mueller@kde.org)
 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2013 Apple Inc. All rights reserved.
 * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIother.m_  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USm_
 *
 */

#ifndef FontDescription_h
#define FontDescription_h

#include "CSSValueKeywords.h"
#include "FontFeatureSettings.h"
#include "TextFlags.h"
#include "WebKitFontFamilyNames.h"
#include <unicode/uscript.h>
#include <wtf/MathExtras.h>
#include <wtf/RefCountedArray.h>
#include <wtf/RefPtr.h>

namespace WebCore {

using namespace WebKitFontFamilyNames;

class FontDescription {
public:
    WEBCORE_EXPORT FontDescription();

    bool operator==(const FontDescription&) const;
    bool operator!=(const FontDescription& other) const { return !(*this == other); }

    float computedSize() const { return m_computedSize; }
    FontItalic italic() const { return static_cast<FontItalic>(m_italic); }
    int computedPixelSize() const { return int(m_computedSize + 0.5f); }
    FontWeight weight() const { return static_cast<FontWeight>(m_weight); }
    FontWeight lighterWeight() const;
    FontWeight bolderWeight() const;
    FontRenderingMode renderingMode() const { return static_cast<FontRenderingMode>(m_renderingMode); }
    TextRenderingMode textRenderingMode() const { return static_cast<TextRenderingMode>(m_textRendering); }
    UScriptCode script() const { return static_cast<UScriptCode>(m_script); }
    const AtomicString& locale() const { return m_locale; }

    FontOrientation orientation() const { return static_cast<FontOrientation>(m_orientation); }
    NonCJKGlyphOrientation nonCJKGlyphOrientation() const { return static_cast<NonCJKGlyphOrientation>(m_nonCJKGlyphOrientation); }
    FontWidthVariant widthVariant() const { return static_cast<FontWidthVariant>(m_widthVariant); }
    const FontFeatureSettings& featureSettings() const { return m_featureSettings; }
    FontSynthesis fontSynthesis() const { return static_cast<FontSynthesis>(m_fontSynthesis); }
    FontVariantLigatures variantCommonLigatures() const { return static_cast<FontVariantLigatures>(m_variantCommonLigatures); }
    FontVariantLigatures variantDiscretionaryLigatures() const { return static_cast<FontVariantLigatures>(m_variantDiscretionaryLigatures); }
    FontVariantLigatures variantHistoricalLigatures() const { return static_cast<FontVariantLigatures>(m_variantHistoricalLigatures); }
    FontVariantLigatures variantContextualAlternates() const { return static_cast<FontVariantLigatures>(m_variantContextualAlternates); }
    FontVariantPosition variantPosition() const { return static_cast<FontVariantPosition>(m_variantPosition); }
    FontVariantCaps variantCaps() const { return static_cast<FontVariantCaps>(m_variantCaps); }
    FontVariantNumericFigure variantNumericFigure() const { return static_cast<FontVariantNumericFigure>(m_variantNumericFigure); }
    FontVariantNumericSpacing variantNumericSpacing() const { return static_cast<FontVariantNumericSpacing>(m_variantNumericSpacing); }
    FontVariantNumericFraction variantNumericFraction() const { return static_cast<FontVariantNumericFraction>(m_variantNumericFraction); }
    FontVariantNumericOrdinal variantNumericOrdinal() const { return static_cast<FontVariantNumericOrdinal>(m_variantNumericOrdinal); }
    FontVariantNumericSlashedZero variantNumericSlashedZero() const { return static_cast<FontVariantNumericSlashedZero>(m_variantNumericSlashedZero); }
    FontVariantAlternates variantAlternates() const { return static_cast<FontVariantAlternates>(m_variantAlternates); }
    FontVariantEastAsianVariant variantEastAsianVariant() const { return static_cast<FontVariantEastAsianVariant>(m_variantEastAsianVariant); }
    FontVariantEastAsianWidth variantEastAsianWidth() const { return static_cast<FontVariantEastAsianWidth>(m_variantEastAsianWidth); }
    FontVariantEastAsianRuby variantEastAsianRuby() const { return static_cast<FontVariantEastAsianRuby>(m_variantEastAsianRuby); }
    FontVariantSettings variantSettings() const
    {
        return { variantCommonLigatures(),
            variantDiscretionaryLigatures(),
            variantHistoricalLigatures(),
            variantContextualAlternates(),
            variantPosition(),
            variantCaps(),
            variantNumericFigure(),
            variantNumericSpacing(),
            variantNumericFraction(),
            variantNumericOrdinal(),
            variantNumericSlashedZero(),
            variantAlternates(),
            variantEastAsianVariant(),
            variantEastAsianWidth(),
            variantEastAsianRuby() };
    }

    void setComputedSize(float s) { m_computedSize = clampToFloat(s); }
    void setItalic(FontItalic i) { m_italic = i; }
    void setIsItalic(bool i) { setItalic(i ? FontItalicOn : FontItalicOff); }
    void setWeight(FontWeight w) { m_weight = w; }
    void setRenderingMode(FontRenderingMode mode) { m_renderingMode = static_cast<unsigned>(mode); }
    void setTextRenderingMode(TextRenderingMode rendering) { m_textRendering = rendering; }
    void setOrientation(FontOrientation orientation) { m_orientation = orientation; }
    void setNonCJKGlyphOrientation(NonCJKGlyphOrientation orientation) { m_nonCJKGlyphOrientation = static_cast<unsigned>(orientation); }
    void setWidthVariant(FontWidthVariant widthVariant) { m_widthVariant = widthVariant; } // Make sure new callers of this sync with FontPlatformData::isForTextCombine()!
    void setLocale(const AtomicString&);
    void setFeatureSettings(FontFeatureSettings&& settings) { m_featureSettings = WTFMove(settings); }
    void setFontSynthesis(FontSynthesis fontSynthesis) { m_fontSynthesis = fontSynthesis; }
    void setVariantCommonLigatures(FontVariantLigatures variant) { m_variantCommonLigatures = static_cast<unsigned>(variant); }
    void setVariantDiscretionaryLigatures(FontVariantLigatures variant) { m_variantDiscretionaryLigatures = static_cast<unsigned>(variant); }
    void setVariantHistoricalLigatures(FontVariantLigatures variant) { m_variantHistoricalLigatures = static_cast<unsigned>(variant); }
    void setVariantContextualAlternates(FontVariantLigatures variant) { m_variantContextualAlternates = static_cast<unsigned>(variant); }
    void setVariantPosition(FontVariantPosition variant) { m_variantPosition = static_cast<unsigned>(variant); }
    void setVariantCaps(FontVariantCaps variant) { m_variantCaps = static_cast<unsigned>(variant); }
    void setVariantNumericFigure(FontVariantNumericFigure variant) { m_variantNumericFigure = static_cast<unsigned>(variant); }
    void setVariantNumericSpacing(FontVariantNumericSpacing variant) { m_variantNumericSpacing = static_cast<unsigned>(variant); }
    void setVariantNumericFraction(FontVariantNumericFraction variant) { m_variantNumericFraction = static_cast<unsigned>(variant); }
    void setVariantNumericOrdinal(FontVariantNumericOrdinal variant) { m_variantNumericOrdinal = static_cast<unsigned>(variant); }
    void setVariantNumericSlashedZero(FontVariantNumericSlashedZero variant) { m_variantNumericSlashedZero = static_cast<unsigned>(variant); }
    void setVariantAlternates(FontVariantAlternates variant) { m_variantAlternates = static_cast<unsigned>(variant); }
    void setVariantEastAsianVariant(FontVariantEastAsianVariant variant) { m_variantEastAsianVariant = static_cast<unsigned>(variant); }
    void setVariantEastAsianWidth(FontVariantEastAsianWidth variant) { m_variantEastAsianWidth = static_cast<unsigned>(variant); }
    void setVariantEastAsianRuby(FontVariantEastAsianRuby variant) { m_variantEastAsianRuby = static_cast<unsigned>(variant); }

    FontTraitsMask traitsMask() const;

private:
    FontFeatureSettings m_featureSettings;
    AtomicString m_locale;

    float m_computedSize { 0 }; // Computed size adjusted for the minimum font size and the zoom factor.
    unsigned m_orientation : 1; // FontOrientation - Whether the font is rendering on a horizontal line or a vertical line.
    unsigned m_nonCJKGlyphOrientation : 1; // NonCJKGlyphOrientation - Only used by vertical text. Determines the default orientation for non-ideograph glyphs.
    unsigned m_widthVariant : 2; // FontWidthVariant
    unsigned m_italic : 1; // FontItalic
    unsigned m_weight : 8; // FontWeight
    unsigned m_renderingMode : 1; // Used to switch between CG and GDI text on Windows.
    unsigned m_textRendering : 2; // TextRenderingMode
    unsigned m_script : 7; // Used to help choose an appropriate font for generic font families.
    unsigned m_fontSynthesis : 2; // FontSynthesis type
    unsigned m_variantCommonLigatures : 2; // FontVariantLigatures
    unsigned m_variantDiscretionaryLigatures : 2; // FontVariantLigatures
    unsigned m_variantHistoricalLigatures : 2; // FontVariantLigatures
    unsigned m_variantContextualAlternates : 2; // FontVariantLigatures
    unsigned m_variantPosition : 2; // FontVariantPosition
    unsigned m_variantCaps : 3; // FontVariantCaps
    unsigned m_variantNumericFigure : 2; // FontVariantNumericFigure
    unsigned m_variantNumericSpacing : 2; // FontVariantNumericSpacing
    unsigned m_variantNumericFraction : 2; // FontVariantNumericFraction
    unsigned m_variantNumericOrdinal : 1; // FontVariantNumericOrdinal
    unsigned m_variantNumericSlashedZero : 1; // FontVariantNumericSlashedZero
    unsigned m_variantAlternates : 1; // FontVariantAlternates
    unsigned m_variantEastAsianVariant : 3; // FontVariantEastAsianVariant
    unsigned m_variantEastAsianWidth : 2; // FontVariantEastAsianWidth
    unsigned m_variantEastAsianRuby : 1; // FontVariantEastAsianRuby
};

inline bool FontDescription::operator==(const FontDescription& other) const
{
    return m_computedSize == other.m_computedSize
        && m_italic == other.m_italic
        && m_weight == other.m_weight
        && m_renderingMode == other.m_renderingMode
        && m_textRendering == other.m_textRendering
        && m_orientation == other.m_orientation
        && m_nonCJKGlyphOrientation == other.m_nonCJKGlyphOrientation
        && m_widthVariant == other.m_widthVariant
        && m_locale == other.m_locale
        && m_featureSettings == other.m_featureSettings
        && m_fontSynthesis == other.m_fontSynthesis
        && m_variantCommonLigatures == other.m_variantCommonLigatures
        && m_variantDiscretionaryLigatures == other.m_variantDiscretionaryLigatures
        && m_variantHistoricalLigatures == other.m_variantHistoricalLigatures
        && m_variantContextualAlternates == other.m_variantContextualAlternates
        && m_variantPosition == other.m_variantPosition
        && m_variantCaps == other.m_variantCaps
        && m_variantNumericFigure == other.m_variantNumericFigure
        && m_variantNumericSpacing == other.m_variantNumericSpacing
        && m_variantNumericFraction == other.m_variantNumericFraction
        && m_variantNumericOrdinal == other.m_variantNumericOrdinal
        && m_variantNumericSlashedZero == other.m_variantNumericSlashedZero
        && m_variantAlternates == other.m_variantAlternates
        && m_variantEastAsianVariant == other.m_variantEastAsianVariant
        && m_variantEastAsianWidth == other.m_variantEastAsianWidth
        && m_variantEastAsianRuby == other.m_variantEastAsianRuby;
}

// FIXME: Move to a file of its own.
class FontCascadeDescription : public FontDescription {
public:
    FontCascadeDescription();

    bool operator==(const FontCascadeDescription&) const;
    bool operator!=(const FontCascadeDescription& other) const { return !(*this == other); }

    unsigned familyCount() const { return m_families.size(); }
    const AtomicString& firstFamily() const { return familyAt(0); }
    const AtomicString& familyAt(unsigned i) const { return m_families[i]; }
    const RefCountedArray<AtomicString>& families() const { return m_families; }

    float specifiedSize() const { return m_specifiedSize; }
    bool isAbsoluteSize() const { return m_isAbsoluteSize; }
    FontWeight lighterWeight() const;
    FontWeight bolderWeight() const;

    // only use fixed default size when there is only one font family, and that family is "monospace"
    bool useFixedDefaultSize() const { return familyCount() == 1 && firstFamily() == monospaceFamily; }

    Kerning kerning() const { return static_cast<Kerning>(m_kerning); }
    unsigned keywordSize() const { return m_keywordSize; }
    CSSValueID keywordSizeAsIdentifier() const
    {
        CSSValueID identifier = m_keywordSize ? static_cast<CSSValueID>(CSSValueXxSmall + m_keywordSize - 1) : CSSValueInvalid;
        ASSERT(identifier == CSSValueInvalid || (identifier >= CSSValueXxSmall && identifier <= CSSValueWebkitXxxLarge));
        return identifier;
    }
    FontSmoothingMode fontSmoothing() const { return static_cast<FontSmoothingMode>(m_fontSmoothing); }
    bool isSpecifiedFont() const { return m_isSpecifiedFont; }

    void setOneFamily(const AtomicString& family) { ASSERT(m_families.size() == 1); m_families[0] = family; }
    void setFamilies(const Vector<AtomicString>& families) { m_families = RefCountedArray<AtomicString>(families); }
    void setFamilies(const RefCountedArray<AtomicString>& families) { m_families = families; }
    void setSpecifiedSize(float s) { m_specifiedSize = clampToFloat(s); }
    void setIsAbsoluteSize(bool s) { m_isAbsoluteSize = s; }
    void setKerning(Kerning kerning) { m_kerning = static_cast<unsigned>(kerning); }
    void setKeywordSize(unsigned size)
    {
        ASSERT(size <= 8);
        m_keywordSize = size;
        ASSERT(m_keywordSize == size); // Make sure it fits in the bitfield.
    }
    void setKeywordSizeFromIdentifier(CSSValueID identifier)
    {
        ASSERT(!identifier || (identifier >= CSSValueXxSmall && identifier <= CSSValueWebkitXxxLarge));
        static_assert(CSSValueWebkitXxxLarge - CSSValueXxSmall + 1 == 8, "Maximum keyword size should be 8.");
        setKeywordSize(identifier ? identifier - CSSValueXxSmall + 1 : 0);
    }
    void setFontSmoothing(FontSmoothingMode smoothing) { m_fontSmoothing = smoothing; }
    void setIsSpecifiedFont(bool isSpecifiedFont) { m_isSpecifiedFont = isSpecifiedFont; }

#if ENABLE(IOS_TEXT_AUTOSIZING)
    bool familiesEqualForTextAutoSizing(const FontCascadeDescription& other) const;

    bool equalForTextAutoSizing(const FontCascadeDescription& other) const
    {
        return familiesEqualForTextAutoSizing(other)
            && m_specifiedSize == other.m_specifiedSize
            && variantSettings() == other.variantSettings()
            && m_isAbsoluteSize == other.m_isAbsoluteSize;
    }
#endif

    // Initial values for font properties.
    static FontItalic initialItalic() { return FontItalicOff; }
    static FontSmallCaps initialSmallCaps() { return FontSmallCapsOff; }
    static Kerning initialKerning() { return Kerning::Auto; }
    static FontSmoothingMode initialFontSmoothing() { return AutoSmoothing; }
    static TextRenderingMode initialTextRenderingMode() { return AutoTextRendering; }
    static FontSynthesis initialFontSynthesis() { return FontSynthesisWeight | FontSynthesisStyle; }
    static FontVariantPosition initialVariantPosition() { return FontVariantPosition::Normal; }
    static FontVariantCaps initialVariantCaps() { return FontVariantCaps::Normal; }
    static FontVariantAlternates initialVariantAlternates() { return FontVariantAlternates::Normal; }
    static const AtomicString& initialLocale() { return nullAtom; }

private:
    RefCountedArray<AtomicString> m_families { 1 };

    float m_specifiedSize { 0 };   // Specified CSS value. Independent of rendering issues such as integer
                             // rounding, minimum font sizes, and zooming.
    unsigned m_isAbsoluteSize : 1; // Whether or not CSS specified an explicit size
                                  // (logical sizes like "medium" don't count).
    unsigned m_kerning : 2; // Kerning

    unsigned m_keywordSize : 4; // We cache whether or not a font is currently represented by a CSS keyword (e.g., medium).  If so,
                           // then we can accurately translate across different generic families to adjust for different preference settings
                           // (e.g., 13px monospace vs. 16px everything else).  Sizes are 1-8 (like the HTML size values for <font>).

    unsigned m_fontSmoothing : 2; // FontSmoothingMode
    unsigned m_isSpecifiedFont : 1; // True if a web page specifies a non-generic font family as the first font family.
};

inline bool FontCascadeDescription::operator==(const FontCascadeDescription& other) const
{
    return FontDescription::operator==(other)
        && m_families == other.m_families
        && m_specifiedSize == other.m_specifiedSize
        && m_isAbsoluteSize == other.m_isAbsoluteSize
        && m_kerning == other.m_kerning
        && m_keywordSize == other.m_keywordSize
        && m_fontSmoothing == other.m_fontSmoothing
        && m_isSpecifiedFont == other.m_isSpecifiedFont;
}

}

#endif