text: /****************************************************************************
  **
  ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
  ** All rights reserved.
  ** Contact: Nokia Corporation (qt-info@nokia.com)
  **
  ** This file is part of the QtGui module of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:LGPL$
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  **
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  ** rights. These rights are described in the Nokia Qt LGPL Exception
  ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
  **
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  ** Alternatively, this file may be used under the terms of the GNU General
  ** Public License version 3.0 as published by the Free Software Foundation
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  ** file. Please review the following information to ensure the GNU General
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  ** http://www.gnu.org/copyleft/gpl.html.
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  ** Alternatively, this file may be used in accordance with the terms and
  ** conditions contained in a signed written agreement between you and Nokia.
  **
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  ****************************************************************************/
  
  #include "qfont.h"
  #include "qdebug.h"
  #include "qpaintdevice.h"
  #include "qfontdatabase.h"
  #include "qfontmetrics.h"
  #include "qfontinfo.h"
  #include "qpainter.h"
  #include "qhash.h"
  #include "qdatastream.h"
  #include "qapplication.h"
  #include "qstringlist.h"
  
  #include "qthread.h"
  #include "qthreadstorage.h"
  
  #include <private/qunicodetables_p.h>
  #include "qfont_p.h"
  #include <private/qfontengine_p.h>
  #include <private/qpainter_p.h>
  #include <private/qtextengine_p.h>
  #include <limits.h>
  
  #ifdef Q_WS_X11
  #include "qx11info_x11.h"
  #include <private/qt_x11_p.h>
  #endif
  #ifdef Q_WS_QWS
  #include "qscreen_qws.h"
  #if !defined(QT_NO_QWS_QPF2)
  #include <qfile.h>
  #include "qfontengine_qpf_p.h"
  #endif
  #endif
  #ifdef Q_OS_SYMBIAN
  #include <private/qt_s60_p.h>
  #endif
  #ifdef Q_WS_QPA
  #include <QtGui/qplatformscreen_qpa.h>
  #include <QtGui/private/qapplication_p.h>
  #endif
  
  #include <QMutexLocker>
  
  // #define QFONTCACHE_DEBUG
  #ifdef QFONTCACHE_DEBUG
  #  define FC_DEBUG qDebug
  #else
  #  define FC_DEBUG if (false) qDebug
  #endif
  
  QT_BEGIN_NAMESPACE
  
  #ifdef Q_WS_WIN
  extern HDC shared_dc();
  #endif
  
  #ifdef Q_WS_X11
  extern const QX11Info *qt_x11Info(const QPaintDevice *pd);
  #endif
  
  bool QFontDef::exactMatch(const QFontDef &other) const
  {
      /*
        QFontDef comparison is more complicated than just simple
        per-member comparisons.
  
        When comparing point/pixel sizes, either point or pixelsize
        could be -1.  in This case we have to compare the non negative
        size value.
  
        This test will fail if the point-sizes differ by 1/2 point or
        more or they do not round to the same value.  We have to do this
        since our API still uses 'int' point-sizes in the API, but store
        deci-point-sizes internally.
  
        To compare the family members, we need to parse the font names
        and compare the family/foundry strings separately.  This allows
        us to compare e.g. "Helvetica" and "Helvetica [Adobe]" with
        positive results.
      */
      if (pixelSize != -1 && other.pixelSize != -1) {
          if (pixelSize != other.pixelSize)
              return false;
      } else if (pointSize != -1 && other.pointSize != -1) {
          if (pointSize != other.pointSize)
              return false;
      } else {
          return false;
      }
  
      if (!ignorePitch && !other.ignorePitch && fixedPitch != other.fixedPitch)
          return false;
  
      if (stretch != 0 && other.stretch != 0 && stretch != other.stretch)
          return false;
  
      QString this_family, this_foundry, other_family, other_foundry;
      QFontDatabase::parseFontName(family, this_foundry, this_family);
      QFontDatabase::parseFontName(other.family, other_foundry, other_family);
  
      this_family = QFontDatabase::resolveFontFamilyAlias(this_family);
      other_family = QFontDatabase::resolveFontFamilyAlias(other_family);
  
      return (styleHint     == other.styleHint
              && styleStrategy == other.styleStrategy
              && weight        == other.weight
              && style        == other.style
              && this_family   == other_family
              && (styleName.isEmpty() || other.styleName.isEmpty() || styleName == other.styleName)
              && (this_foundry.isEmpty()
                  || other_foundry.isEmpty()
                  || this_foundry == other_foundry)
  #ifdef Q_WS_X11
              && addStyle == other.addStyle
  #endif // Q_WS_X11
         );
  }
  
  extern bool qt_is_gui_used;
  
  Q_GUI_EXPORT int qt_defaultDpiX()
  {
      if (!qt_is_gui_used)
          return 75;
  
      int dpi;
  #ifdef Q_WS_X11
      dpi = QX11Info::appDpiX();
  #elif defined(Q_WS_WIN)
      dpi = GetDeviceCaps(shared_dc(),LOGPIXELSX);
  #elif defined(Q_WS_MAC)
      extern float qt_mac_defaultDpi_x(); //qpaintdevice_mac.cpp
      dpi = qt_mac_defaultDpi_x();
  #elif defined(Q_WS_QWS)
      if (!qt_screen)
          return 72;
      QScreen *screen = qt_screen;
      const QList<QScreen*> subScreens = qt_screen->subScreens();
      if (!subScreens.isEmpty())
          screen = subScreens.at(0);
      dpi = qRound(screen->width() / (screen->physicalWidth() / qreal(25.4)));
  #elif defined(Q_WS_QPA)
      QPlatformIntegration *pi = QApplicationPrivate::platformIntegration();
      if (pi) {
          QPlatformScreen *screen = QApplicationPrivate::platformIntegration()->screens().at(0);
          const QSize screenSize = screen->geometry().size();
          const QSize physicalSize = screen->physicalSize();
          dpi = qRound(screenSize.width() / (physicalSize.width() / qreal(25.4)));
      } else {
          //PI has not been initialised, or it is being initialised. Give a default dpi
          dpi = 100;
      }
  #elif defined(Q_OS_SYMBIAN)
      dpi = S60->defaultDpiX;
  #endif // Q_WS_X11
  
      return dpi;
  }
  
  Q_GUI_EXPORT int qt_defaultDpiY()
  {
      if (!qt_is_gui_used)
          return 75;
  
      int dpi;
  #ifdef Q_WS_X11
      dpi = QX11Info::appDpiY();
  #elif defined(Q_WS_WIN)
      dpi = GetDeviceCaps(shared_dc(),LOGPIXELSY);
  #elif defined(Q_WS_MAC)
      extern float qt_mac_defaultDpi_y(); //qpaintdevice_mac.cpp
      dpi = qt_mac_defaultDpi_y();
  #elif defined(Q_WS_QWS)
      if (!qt_screen)
          return 72;
      QScreen *screen = qt_screen;
      const QList<QScreen*> subScreens = qt_screen->subScreens();
      if (!subScreens.isEmpty())
          screen = subScreens.at(0);
      dpi = qRound(screen->height() / (screen->physicalHeight() / qreal(25.4)));
  #elif defined(Q_WS_QPA)
      QPlatformIntegration *pi = QApplicationPrivate::platformIntegration();
      if (pi) {
          QPlatformScreen *screen = QApplicationPrivate::platformIntegration()->screens().at(0);
          const QSize screenSize = screen->geometry().size();
          const QSize physicalSize = screen->physicalSize();
          dpi = qRound(screenSize.height() / (physicalSize.height() / qreal(25.4)));
      } else {
          //PI has not been initialised, or it is being initialised. Give a default dpi
          dpi = 100;
      }
  #elif defined(Q_OS_SYMBIAN)
      dpi = S60->defaultDpiY;
  #endif // Q_WS_X11
  
      return dpi;
  }
  
  Q_GUI_EXPORT int qt_defaultDpi()
  {
      return qt_defaultDpiY();
  }
  
  QFontPrivate::QFontPrivate()
      : engineData(0), dpi(qt_defaultDpi()), screen(0),
        rawMode(false), underline(false), overline(false), strikeOut(false), kerning(true),
        capital(0), letterSpacingIsAbsolute(false), scFont(0)
  {
  #ifdef Q_WS_X11
      if (QX11Info::display())
          screen = QX11Info::appScreen();
      else
          screen = 0;
  #endif
  #ifdef Q_WS_WIN
      hdc = 0;
  #endif
  }
  
  QFontPrivate::QFontPrivate(const QFontPrivate &other)
      : request(other.request), engineData(0), dpi(other.dpi), screen(other.screen),
        rawMode(other.rawMode), underline(other.underline), overline(other.overline),
        strikeOut(other.strikeOut), kerning(other.kerning),
        capital(other.capital), letterSpacingIsAbsolute(other.letterSpacingIsAbsolute),
        letterSpacing(other.letterSpacing), wordSpacing(other.wordSpacing),
        scFont(other.scFont)
  {
  #ifdef Q_WS_WIN
      hdc = other.hdc;
  #endif
      if (scFont && scFont != this)
          scFont->ref.ref();
  }
  
  QFontPrivate::~QFontPrivate()
  {
      if (engineData)
          engineData->ref.deref();
      engineData = 0;
      if (scFont && scFont != this)
          scFont->ref.deref();
      scFont = 0;
  }
  
  extern QMutex *qt_fontdatabase_mutex();
  
  #if !defined(Q_WS_MAC)
  #define QT_FONT_ENGINE_FROM_DATA(data, script) data->engines[script]
  #else
  #define QT_FONT_ENGINE_FROM_DATA(data, script) data->engine
  #endif
  
  QFontEngine *QFontPrivate::engineForScript(int script) const
  {
      QMutexLocker locker(qt_fontdatabase_mutex());
      if (script >= QUnicodeTables::Inherited)
          script = QUnicodeTables::Common;
      if (engineData && engineData->fontCache != QFontCache::instance()) {
          // throw out engineData that came from a different thread
          engineData->ref.deref();
          engineData = 0;
      }
      if (!engineData || !QT_FONT_ENGINE_FROM_DATA(engineData, script))
          QFontDatabase::load(this, script);
      return QT_FONT_ENGINE_FROM_DATA(engineData, script);
  }
  
  void QFontPrivate::alterCharForCapitalization(QChar &c) const {
      switch (capital) {
      case QFont::AllUppercase:
      case QFont::SmallCaps:
          c = c.toUpper();
          break;
      case QFont::AllLowercase:
          c = c.toLower();
          break;
      case QFont::MixedCase:
          break;
      }
  }
  
  QFontPrivate *QFontPrivate::smallCapsFontPrivate() const
  {
      if (scFont)
          return scFont;
      QFont font(const_cast<QFontPrivate *>(this));
      qreal pointSize = font.pointSizeF();
      if (pointSize > 0)
          font.setPointSizeF(pointSize * .7);
      else
          font.setPixelSize((font.pixelSize() * 7 + 5) / 10);
      scFont = font.d.data();
      if (scFont != this)
          scFont->ref.ref();
      return scFont;
  }
  
  
  void QFontPrivate::resolve(uint mask, const QFontPrivate *other)
  {
      Q_ASSERT(other != 0);
  
      dpi = other->dpi;
  
      if ((mask & QFont::AllPropertiesResolved) == QFont::AllPropertiesResolved) return;
  
      // assign the unset-bits with the set-bits of the other font def
      if (! (mask & QFont::FamilyResolved))
          request.family = other->request.family;
  
      if (! (mask & QFont::StyleNameResolved))
          request.styleName = other->request.styleName;
  
      if (! (mask & QFont::SizeResolved)) {
          request.pointSize = other->request.pointSize;
          request.pixelSize = other->request.pixelSize;
      }
  
      if (! (mask & QFont::StyleHintResolved))
          request.styleHint = other->request.styleHint;
  
      if (! (mask & QFont::StyleStrategyResolved))
          request.styleStrategy = other->request.styleStrategy;
  
      if (! (mask & QFont::WeightResolved))
          request.weight = other->request.weight;
  
      if (! (mask & QFont::StyleResolved))
          request.style = other->request.style;
  
      if (! (mask & QFont::FixedPitchResolved))
          request.fixedPitch = other->request.fixedPitch;
  
      if (! (mask & QFont::StretchResolved))
          request.stretch = other->request.stretch;
  
      if (! (mask & QFont::HintingPreferenceResolved))
          request.hintingPreference = other->request.hintingPreference;
  
      if (! (mask & QFont::UnderlineResolved))
          underline = other->underline;
  
      if (! (mask & QFont::OverlineResolved))
          overline = other->overline;
  
      if (! (mask & QFont::StrikeOutResolved))
          strikeOut = other->strikeOut;
  
      if (! (mask & QFont::KerningResolved))
          kerning = other->kerning;
  
      if (! (mask & QFont::LetterSpacingResolved)) {
          letterSpacing = other->letterSpacing;
          letterSpacingIsAbsolute = other->letterSpacingIsAbsolute;
      }
      if (! (mask & QFont::WordSpacingResolved))
          wordSpacing = other->wordSpacing;
      if (! (mask & QFont::CapitalizationResolved))
          capital = other->capital;
  }
  
  
  
  
  QFontEngineData::QFontEngineData()
      : ref(1), fontCache(QFontCache::instance())
  {
  #if !defined(Q_WS_MAC)
      memset(engines, 0, QUnicodeTables::ScriptCount * sizeof(QFontEngine *));
  #else
      engine = 0;
  #endif
  }
  
  QFontEngineData::~QFontEngineData()
  {
  #if !defined(Q_WS_MAC)
      for (int i = 0; i < QUnicodeTables::ScriptCount; ++i) {
          if (engines[i])
              engines[i]->ref.deref();
          engines[i] = 0;
      }
  #else
      if (engine)
          engine->ref.deref();
      engine = 0;
  #endif // Q_WS_X11 || Q_WS_WIN || Q_WS_MAC
  }
  
  
  
  
  /*!
      \class QFont
      \reentrant
  
      \brief The QFont class specifies a font used for drawing text.
  
      \ingroup painting
      \ingroup appearance
      \ingroup shared
      \ingroup richtext-processing
  
  
      When you create a QFont object you specify various attributes that
      you want the font to have. Qt will use the font with the specified
      attributes, or if no matching font exists, Qt will use the closest
      matching installed font. The attributes of the font that is
      actually used are retrievable from a QFontInfo object. If the
      window system provides an exact match exactMatch() returns true.
      Use QFontMetrics to get measurements, e.g. the pixel length of a
      string using QFontMetrics::width().
  
      Note that a QApplication instance must exist before a QFont can be
      used. You can set the application's default font with
      QApplication::setFont().
  
      If a chosen font does not include all the characters that
      need to be displayed, QFont will try to find the characters in the
      nearest equivalent fonts. When a QPainter draws a character from a
      font the QFont will report whether or not it has the character; if
      it does not, QPainter will draw an unfilled square.
  
      Create QFonts like this:
  
      \snippet doc/src/snippets/code/src_gui_text_qfont.cpp 0
  
      The attributes set in the constructor can also be set later, e.g.
      setFamily(), setPointSize(), setPointSizeFloat(), setWeight() and
      setItalic(). The remaining attributes must be set after
      contstruction, e.g. setBold(), setUnderline(), setOverline(),
      setStrikeOut() and setFixedPitch(). QFontInfo objects should be
      created \e after the font's attributes have been set. A QFontInfo
      object will not change, even if you change the font's
      attributes. The corresponding "get" functions, e.g. family(),
      pointSize(), etc., return the values that were set, even though
      the values used may differ. The actual values are available from a
      QFontInfo object.
  
      If the requested font family is unavailable you can influence the
      \link #fontmatching font matching algorithm\endlink by choosing a
      particular \l{QFont::StyleHint} and \l{QFont::StyleStrategy} with
      setStyleHint(). The default family (corresponding to the current
      style hint) is returned by defaultFamily().
  
      The font-matching algorithm has a lastResortFamily() and
      lastResortFont() in cases where a suitable match cannot be found.
      You can provide substitutions for font family names using
      insertSubstitution() and insertSubstitutions(). Substitutions can
      be removed with removeSubstitution(). Use substitute() to retrieve
      a family's first substitute, or the family name itself if it has
      no substitutes. Use substitutes() to retrieve a list of a family's
      substitutes (which may be empty).
  
      Every QFont has a key() which you can use, for example, as the key
      in a cache or dictionary. If you want to store a user's font
      preferences you could use QSettings, writing the font information
      with toString() and reading it back with fromString(). The
      operator<<() and operator>>() functions are also available, but
      they work on a data stream.
  
      It is possible to set the height of characters shown on the screen
      to a specified number of pixels with setPixelSize(); however using
      setPointSize() has a similar effect and provides device
      independence.
  
      In X11 you can set a font using its system
      specific name with setRawName().
  
      Loading fonts can be expensive, especially on X11. QFont contains
      extensive optimizations to make the copying of QFont objects fast,
      and to cache the results of the slow window system functions it
      depends upon.
  
      \target fontmatching
      The font matching algorithm works as follows:
      \list 1
      \o The specified font family is searched for.
      \o If not found, the styleHint() is used to select a replacement
         family.
      \o Each replacement font family is searched for.
      \o If none of these are found or there was no styleHint(), "helvetica"
         will be searched for.
      \o If "helvetica" isn't found Qt will try the lastResortFamily().
      \o If the lastResortFamily() isn't found Qt will try the
         lastResortFont() which will always return a name of some kind.
      \endlist
  
      Note that the actual font matching algorithm varies from platform to platform.
  
      In Windows a request for the "Courier" font is automatically changed to
      "Courier New", an improved version of Courier that allows for smooth scaling.
      The older "Courier" bitmap font can be selected by setting the PreferBitmap
      style strategy (see setStyleStrategy()).
  
      Once a font is found, the remaining attributes are matched in order of
      priority:
      \list 1
      \o fixedPitch()
      \o pointSize() (see below)
      \o weight()
      \o style()
      \endlist
  
      If you have a font which matches on family, even if none of the
      other attributes match, this font will be chosen in preference to
      a font which doesn't match on family but which does match on the
      other attributes. This is because font family is the dominant
      search criteria.
  
      The point size is defined to match if it is within 20% of the
      requested point size. When several fonts match and are only
      distinguished by point size, the font with the closest point size
      to the one requested will be chosen.
  
      The actual family, font size, weight and other font attributes
      used for drawing text will depend on what's available for the
      chosen family under the window system. A QFontInfo object can be
      used to determine the actual values used for drawing the text.
  
      Examples:
  
      \snippet doc/src/snippets/code/src_gui_text_qfont.cpp 1
      If you had both an Adobe and a Cronyx Helvetica, you might get
      either.
  
      \snippet doc/src/snippets/code/src_gui_text_qfont.cpp 2
  
      You can specify the foundry you want in the family name. The font f
      in the above example will be set to "Helvetica
      [Cronyx]".
  
      To determine the attributes of the font actually used in the window
      system, use a QFontInfo object, e.g.
  
      \snippet doc/src/snippets/code/src_gui_text_qfont.cpp 3
  
      To find out font metrics use a QFontMetrics object, e.g.
  
      \snippet doc/src/snippets/code/src_gui_text_qfont.cpp 4
  
      For more general information on fonts, see the
      \link http://nwalsh.com/comp.fonts/FAQ/ comp.fonts FAQ.\endlink
      Information on encodings can be found from
      \link http://czyborra.com/ Roman Czyborra's\endlink page.
  
      \sa QFontComboBox, QFontMetrics, QFontInfo, QFontDatabase, {Character Map Example}
  */
  
  /*!
      \internal
      \enum QFont::ResolveProperties
  
      This enum describes the properties of a QFont that can be set on a font
      individually and then considered resolved.
  
      \value FamilyResolved
      \value SizeResolved
      \value StyleHintResolved
      \value StyleStrategyResolved
      \value WeightResolved
      \value StyleResolved
      \value UnderlineResolved
      \value OverlineResolved
      \value StrikeOutResolved
      \value FixedPitchResolved
      \value StretchResolved
      \value KerningResolved
      \value CapitalizationResolved
      \value LetterSpacingResolved
      \value WordSpacingResolved
      \value CompletelyResolved
  */
  
  /*!
      \enum QFont::Style
  
      This enum describes the different styles of glyphs that are used to
      display text.
  
      \value StyleNormal  Normal glyphs used in unstyled text.
      \value StyleItalic  Italic glyphs that are specifically designed for
                          the purpose of representing italicized text.
      \value StyleOblique Glyphs with an italic appearance that are typically
                          based on the unstyled glyphs, but are not fine-tuned
                          for the purpose of representing italicized text.
  
      \sa Weight
  */
  
  /*!
      \fn Qt::HANDLE QFont::handle() const
  
      Returns the window system handle to the font, for low-level
      access. Using this function is \e not portable.
  */
  
  /*!
      \fn FT_Face QFont::freetypeFace() const
  
      Returns the handle to the primary FreeType face of the font. If font merging is not disabled a
      QFont can contain several physical fonts.
  
      Returns 0 if the font does not contain a FreeType face.
  
      \note This function is only available on platforms that provide the FreeType library;
      i.e., X11 and some Embedded Linux platforms.
  */
  
  /*!
      \fn QString QFont::rawName() const
  
      Returns the name of the font within the underlying window system.
  
      On X11, this function will return an empty string if Qt is built with
      FontConfig support; otherwise the XLFD (X Logical Font Description) is
      returned.
  
      Using the return value of this function is usually \e not \e
      portable.
  
      \sa setRawName()
  */
  
  /*!
      \fn void QFont::setRawName(const QString &name)
  
      Sets a font by its system specific name. The function is
      particularly useful under X, where system font settings (for
      example X resources) are usually available in XLFD (X Logical Font
      Description) form only. You can pass an XLFD as \a name to this
      function.
  
      A font set with setRawName() is still a full-featured QFont. It can
      be queried (for example with italic()) or modified (for example with
      setItalic()) and is therefore also suitable for rendering rich text.
  
      If Qt's internal font database cannot resolve the raw name, the
      font becomes a raw font with \a name as its family.
  
      Note that the present implementation does not handle wildcards in
      XLFDs well, and that font aliases (file \c fonts.alias in the font
      directory on X11) are not supported.
  
      \sa rawName(), setRawMode(), setFamily()
  */
  
  /*!
      \fn QString QFont::lastResortFamily() const
  
      Returns the "last resort" font family name.
  
      The current implementation tries a wide variety of common fonts,
      returning the first one it finds. Is is possible that no family is
      found in which case an empty string is returned.
  
      \sa lastResortFont()
  */
  
  /*!
      \fn QString QFont::defaultFamily() const
  
      Returns the family name that corresponds to the current style
      hint.
  
      \sa StyleHint styleHint() setStyleHint()
  */
  
  /*!
      \fn QString QFont::lastResortFont() const
  
      Returns a "last resort" font name for the font matching algorithm.
      This is used if the last resort family is not available. It will
      always return a name, if necessary returning something like
      "fixed" or "system".
  
      The current implementation tries a wide variety of common fonts,
      returning the first one it finds. The implementation may change
      at any time, but this function will always return a string
      containing something.
  
      It is theoretically possible that there really isn't a
      lastResortFont() in which case Qt will abort with an error
      message. We have not been able to identify a case where this
      happens. Please \link bughowto.html report it as a bug\endlink if
      it does, preferably with a list of the fonts you have installed.
  
      \sa lastResortFamily() rawName()
  */
  
  /*!
    Constructs a font from \a font for use on the paint device \a pd.
  */
  QFont::QFont(const QFont &font, QPaintDevice *pd)
      : resolve_mask(font.resolve_mask)
  {
      Q_ASSERT(pd != 0);
      int dpi = pd->logicalDpiY();
  #ifdef Q_WS_X11
      const QX11Info *info = qt_x11Info(pd);
      int screen = info ? info->screen() : 0;
  #else
      const int screen = 0;
  #endif
      if (font.d->dpi != dpi || font.d->screen != screen ) {
          d = new QFontPrivate(*font.d);
          d->dpi = dpi;
          d->screen = screen;
      } else {
          d = font.d.data();
      }
  #ifdef Q_WS_WIN
      if (pd->devType() == QInternal::Printer && pd->getDC())
          d->hdc = pd->getDC();
  #endif
  }
  
  /*!
    \internal
  */
  QFont::QFont(QFontPrivate *data)
      : d(data), resolve_mask(QFont::AllPropertiesResolved)
  {
  }
  
  /*! \internal
      Detaches the font object from common font data.
  */
  void QFont::detach()
  {
      if (d->ref == 1) {
          if (d->engineData)
              d->engineData->ref.deref();
          d->engineData = 0;
          if (d->scFont && d->scFont != d.data())
              d->scFont->ref.deref();
          d->scFont = 0;
          return;
      }
  
      d.detach();
  }
  
  /*!
      Constructs a font object that uses the application's default font.
  
      \sa QApplication::setFont(), QApplication::font()
  */
  QFont::QFont()
      : d(QApplication::font().d.data()), resolve_mask(0)
  {
  }
  
  /*!
      Constructs a font object with the specified \a family, \a
      pointSize, \a weight and \a italic settings.
  
      If \a pointSize is zero or negative, the point size of the font
      is set to a system-dependent default value. Generally, this is
      12 points, except on Symbian where it is 7 points.
  
      The \a family name may optionally also include a foundry name,
      e.g. "Helvetica [Cronyx]". If the \a family is
      available from more than one foundry and the foundry isn't
      specified, an arbitrary foundry is chosen. If the family isn't
      available a family will be set using the \l{QFont}{font matching}
      algorithm.
  
      \sa Weight, setFamily(), setPointSize(), setWeight(), setItalic(),
      setStyleHint() QApplication::font()
  */
  QFont::QFont(const QString &family, int pointSize, int weight, bool italic)
      : d(new QFontPrivate()), resolve_mask(QFont::FamilyResolved)
  {
      if (pointSize <= 0) {
  #ifdef Q_OS_SYMBIAN
          pointSize = 7;
  #else
          pointSize = 12;
  #endif
      } else {
          resolve_mask |= QFont::SizeResolved;
      }
  
      if (weight < 0) {
          weight = Normal;
      } else {
          resolve_mask |= QFont::WeightResolved | QFont::StyleResolved;
      }
  
      if (italic)
          resolve_mask |= QFont::StyleResolved;
  
      d->request.family = family;
      d->request.pointSize = qreal(pointSize);
      d->request.pixelSize = -1;
      d->request.weight = weight;
      d->request.style = italic ? QFont::StyleItalic : QFont::StyleNormal;
  }
  
  /*!
      Constructs a font that is a copy of \a font.
  */
  QFont::QFont(const QFont &font)
      : d(font.d.data()), resolve_mask(font.resolve_mask)
  {
  }
  
  /*!
      Destroys the font object and frees all allocated resources.
  */
  QFont::~QFont()
  {
  }
  
  /*!
      Assigns \a font to this font and returns a reference to it.
  */
  QFont &QFont::operator=(const QFont &font)
  {
      d = font.d.data();
      resolve_mask = font.resolve_mask;
      return *this;
  }
  
  /*!
      Returns the requested font family name, i.e. the name set in the
      constructor or the last setFont() call.
  
      \sa setFamily() substitutes() substitute()
  */
  QString QFont::family() const
  {
      return d->request.family;
  }
  
  /*!
      Sets the family name of the font. The name is case insensitive and
      may include a foundry name.
  
      The \a family name may optionally also include a foundry name,
      e.g. "Helvetica [Cronyx]". If the \a family is
      available from more than one foundry and the foundry isn't
      specified, an arbitrary foundry is chosen. If the family isn't
      available a family will be set using the \l{QFont}{font matching}
      algorithm.
  
      \sa family(), setStyleHint(), QFontInfo
  */
  void QFont::setFamily(const QString &family)
  {
      detach();
  
      d->request.family = family;
  #if defined(Q_WS_X11)
      d->request.addStyle.clear();
  #endif // Q_WS_X11
  
      resolve_mask |= QFont::FamilyResolved;
  }
  
  /*!
      \since 4.8
  
      Returns the requested font style name, it will be used to match the
      font with irregular styles (that can't be normalized in other style
      properties). It depends on system font support, thus only works for
      Mac OS X and X11 so far. On Windows irregular styles will be added
      as separate font families so there is no need for this.
  
      \sa setFamily() setStyle()
  */
  QString QFont::styleName() const
  {
      return d->request.styleName;
  }
  
  /*!
      \since 4.8
  
      Sets the style name of the font to the given \a styleName.
      When set, other style properties like style() and weight() will be ignored
      for font matching.
  
      \sa styleName()
  */
  void QFont::setStyleName(const QString &styleName)
  {
      detach();
  
      d->request.styleName = styleName;
      resolve_mask |= QFont::StyleNameResolved;
  }
  
  /*!
      Returns the point size of the font. Returns -1 if the font size
      was specified in pixels.
  
      \sa setPointSize() pointSizeF()
  */
  int QFont::pointSize() const
  {
      return qRound(d->request.pointSize);
  }
  
  /*!
      \since 4.8
  
      \enum QFont::HintingPreference
  
      This enum describes the different levels of hinting that can be applied
      to glyphs to improve legibility on displays where it might be warranted
      by the density of pixels.
  
      \value PreferDefaultHinting Use the default hinting level for the target platform.
      \value PreferNoHinting If possible, render text without hinting the outlines
             of the glyphs. The text layout will be typographically accurate and
             scalable, using the same metrics as are used e.g. when printing.
      \value PreferVerticalHinting If possible, render text with no horizontal hinting,
             but align glyphs to the pixel grid in the vertical direction. The text will appear
             crisper on displays where the density is too low to give an accurate rendering
             of the glyphs. But since the horizontal metrics of the glyphs are unhinted, the text's
             layout will be scalable to higher density devices (such as printers) without impacting
             details such as line breaks.
      \value PreferFullHinting If possible, render text with hinting in both horizontal and
             vertical directions. The text will be altered to optimize legibility on the target
             device, but since the metrics will depend on the target size of the text, the positions
             of glyphs, line breaks, and other typographical detail will not scale, meaning that a
             text layout may look different on devices with different pixel densities.
  
      Please note that this enum only describes a preference, as the full range of hinting levels
      are not supported on all of Qt's supported platforms. The following table details the effect
      of a given hinting preference on a selected set of target platforms.
  
      \table
      \header
      \o
      \o PreferDefaultHinting
      \o PreferNoHinting
      \o PreferVerticalHinting
      \o PreferFullHinting
      \row
      \o Windows Vista (w/o Platform Update) and earlier
      \o Full hinting
      \o Full hinting
      \o Full hinting
      \o Full hinting
      \row
      \o Windows 7 and Windows Vista (w/Platform Update) and DirectWrite enabled in Qt
      \o Full hinting
      \o Vertical hinting
      \o Vertical hinting
      \o Full hinting
      \row
      \o FreeType
      \o Operating System setting
      \o No hinting
      \o Vertical hinting (light)
      \o Full hinting
      \row
      \o Cocoa on Mac OS X
      \o No hinting
      \o No hinting
      \o No hinting
      \o No hinting
      \endtable
  
      \note Please be aware that altering the hinting preference on Windows is available through
      the DirectWrite font engine. This is available on Windows Vista after installing the platform
      update, and on Windows 7. In order to use this extension, configure Qt using -directwrite.
      The target application will then depend on the availability of DirectWrite on the target
      system.
  
  */
  
  /*!
      \since 4.8
  
      Set the preference for the hinting level of the glyphs to \a hintingPreference. This is a hint
      to the underlying font rendering system to use a certain level of hinting, and has varying
      support across platforms. See the table in the documentation for QFont::HintingPreference for
      more details.
  
      The default hinting preference is QFont::PreferDefaultHinting.
  */
  void QFont::setHintingPreference(HintingPreference hintingPreference)
  {
      detach();
  
      d->request.hintingPreference = hintingPreference;
  
      resolve_mask |= QFont::HintingPreferenceResolved;
  }
  
  /*!
      \since 4.8
  
      Returns the currently preferred hinting level for glyphs rendered with this font.
  */
  QFont::HintingPreference QFont::hintingPreference() const
  {
      return QFont::HintingPreference(d->request.hintingPreference);
  }
  
  /*!
      Sets the point size to \a pointSize. The point size must be
      greater than zero.
  
      \sa pointSize() setPointSizeF()
  */
  void QFont::setPointSize(int pointSize)
  {
      if (pointSize <= 0) {
          qWarning("QFont::setPointSize: Point size <= 0 (%d), must be greater than 0", pointSize);
          return;
      }
  
      detach();
  
      d->request.pointSize = qreal(pointSize);
      d->request.pixelSize = -1;
  
      resolve_mask |= QFont::SizeResolved;
  }
  
  /*!
      Sets the point size to \a pointSize. The point size must be
      greater than zero. The requested precision may not be achieved on
      all platforms.
  
      \sa pointSizeF() setPointSize() setPixelSize()
  */
  void QFont::setPointSizeF(qreal pointSize)
  {
      if (pointSize <= 0) {
          qWarning("QFont::setPointSizeF: Point size <= 0 (%f), must be greater than 0", pointSize);
          return;
      }
  
      detach();
  
      d->request.pointSize = pointSize;
      d->request.pixelSize = -1;
  
      resolve_mask |= QFont::SizeResolved;
  }
  
  /*!
      Returns the point size of the font. Returns -1 if the font size was
      specified in pixels.
  
      \sa pointSize() setPointSizeF() pixelSize() QFontInfo::pointSize() QFontInfo::pixelSize()
  */
  qreal QFont::pointSizeF() const
  {
      return d->request.pointSize;
  }
  
  /*!
      Sets the font size to \a pixelSize pixels.
  
      Using this function makes the font device dependent. Use
      setPointSize() or setPointSizeF() to set the size of the font
      in a device independent manner.
  
      \sa pixelSize()
  */
  void QFont::setPixelSize(int pixelSize)
  {
      if (pixelSize <= 0) {
          qWarning("QFont::setPixelSize: Pixel size <= 0 (%d)", pixelSize);
          return;
      }
  
      detach();
  
      d->request.pixelSize = pixelSize;
      d->request.pointSize = -1;
  
      resolve_mask |= QFont::SizeResolved;
  }
  
  /*!
      Returns the pixel size of the font if it was set with
      setPixelSize(). Returns -1 if the size was set with setPointSize()
      or setPointSizeF().
  
      \sa setPixelSize() pointSize() QFontInfo::pointSize() QFontInfo::pixelSize()
  */
  int QFont::pixelSize() const
  {
      return d->request.pixelSize;
  }
  
  #ifdef QT3_SUPPORT
  /*! \obsolete
  
    Sets the logical pixel height of font characters when shown on
    the screen to \a pixelSize.
  */
  void QFont::setPixelSizeFloat(qreal pixelSize)
  {
      setPixelSize((int)pixelSize);
  }
  #endif
  
  /*!
    \fn bool QFont::italic() const
  
      Returns true if the style() of the font is not QFont::StyleNormal
  
      \sa setItalic() style()
  */
  
  /*!
    \fn void QFont::setItalic(bool enable)
  
    Sets the style() of the font to QFont::StyleItalic if \a enable is true;
    otherwise the style is set to QFont::StyleNormal.
  
    \sa italic() QFontInfo
  */
  
  /*!
      Returns the style of the font.
  
      \sa setStyle()
  */
  QFont::Style QFont::style() const
  {
      return (QFont::Style)d->request.style;
  }
  
  
  /*!
    Sets the style of the font to \a style.
  
    \sa italic(), QFontInfo
  */
  void QFont::setStyle(Style style)
  {
      detach();
  
      d->request.style = style;
      resolve_mask |= QFont::StyleResolved;
  }
  
  /*!
      Returns the weight of the font which is one of the enumerated
      values from \l{QFont::Weight}.
  
      \sa setWeight(), Weight, QFontInfo
  */
  int QFont::weight() const
  {
      return d->request.weight;
  }
  
  /*!
      \enum QFont::Weight
  
      Qt uses a weighting scale from 0 to 99 similar to, but not the
      same as, the scales used in Windows or CSS. A weight of 0 is
      ultralight, whilst 99 will be an extremely black.
  
      This enum contains the predefined font weights:
  
      \value Light 25
      \value Normal 50
      \value DemiBold 63
      \value Bold 75
      \value Black 87
  */
  
  /*!
      Sets the weight the font to \a weight, which should be a value
      from the \l QFont::Weight enumeration.
  
      \sa weight(), QFontInfo
  */
  void QFont::setWeight(int weight)
  {
      Q_ASSERT_X(weight >= 0 && weight <= 99, "QFont::setWeight", "Weight must be between 0 and 99");
  
      detach();
  
      d->request.weight = weight;
      resolve_mask |= QFont::WeightResolved;
  }
  
  /*!
      \fn bool QFont::bold() const
  
      Returns true if weight() is a value greater than \link Weight
      QFont::Normal \endlink; otherwise returns false.
  
      \sa weight(), setBold(), QFontInfo::bold()
  */
  
  /*!
      \fn void QFont::setBold(bool enable)
  
      If \a enable is true sets the font's weight to \link Weight
      QFont::Bold \endlink; otherwise sets the weight to \link Weight
      QFont::Normal\endlink.
  
      For finer boldness control use setWeight().
  
      \sa bold(), setWeight()
  */
  
  /*!
      Returns true if underline has been set; otherwise returns false.
  
      \sa setUnderline()
  */
  bool QFont::underline() const
  {
      return d->underline;
  }
  
  /*!
      If \a enable is true, sets underline on; otherwise sets underline
      off.
  
      \sa underline(), QFontInfo
  */
  void QFont::setUnderline(bool enable)
  {
      detach();
  
      d->underline = enable;
      resolve_mask |= QFont::UnderlineResolved;
  }
  
  /*!
      Returns true if overline has been set; otherwise returns false.
  
      \sa setOverline()
  */
  bool QFont::overline() const
  {
      return d->overline;
  }
  
  /*!
    If \a enable is true, sets overline on; otherwise sets overline off.
  
    \sa overline(), QFontInfo
  */
  void QFont::setOverline(bool enable)
  {
      detach();
  
      d->overline = enable;
      resolve_mask |= QFont::OverlineResolved;
  }
  
  /*!
      Returns true if strikeout has been set; otherwise returns false.
  
      \sa setStrikeOut()
  */
  bool QFont::strikeOut() const
  {
      return d->strikeOut;
  }
  
  /*!
      If \a enable is true, sets strikeout on; otherwise sets strikeout
      off.
  
      \sa strikeOut(), QFontInfo
  */
  void QFont::setStrikeOut(bool enable)
  {
      detach();
  
      d->strikeOut = enable;
      resolve_mask |= QFont::StrikeOutResolved;
  }
  
  /*!
      Returns true if fixed pitch has been set; otherwise returns false.
  
      \sa setFixedPitch(), QFontInfo::fixedPitch()
  */
  bool QFont::fixedPitch() const
  {
      return d->request.fixedPitch;
  }
  
  /*!
      If \a enable is true, sets fixed pitch on; otherwise sets fixed
      pitch off.
  
      \sa fixedPitch(), QFontInfo
  */
  void QFont::setFixedPitch(bool enable)
  {
      detach();
  
      d->request.fixedPitch = enable;
      d->request.ignorePitch = false;
      resolve_mask |= QFont::FixedPitchResolved;
  }
  
  /*!
    Returns true if kerning should be used when drawing text with this font.
  
    \sa setKerning()
  */
  bool QFont::kerning() const
  {
      return d->kerning;
  }
  
  /*!
      Enables kerning for this font if \a enable is true; otherwise
      disables it. By default, kerning is enabled.
  
      When kerning is enabled, glyph metrics do not add up anymore,
      even for Latin text. In other words, the assumption that
      width('a') + width('b') is equal to width("ab") is not
      neccesairly true.
  
      \sa kerning(), QFontMetrics
  */
  void QFont::setKerning(bool enable)
  {
      detach();
      d->kerning = enable;
      resolve_mask |= QFont::KerningResolved;
  }
  
  /*!
      Returns the StyleStrategy.
  
      The style strategy affects the \l{QFont}{font matching} algorithm.
      See \l QFont::StyleStrategy for the list of available strategies.
  
      \sa setStyleHint() QFont::StyleHint
  */
  QFont::StyleStrategy QFont::styleStrategy() const
  {
      return (StyleStrategy) d->request.styleStrategy;
  }
  
  /*!
      Returns the StyleHint.
  
      The style hint affects the \l{QFont}{font matching} algorithm.
      See \l QFont::StyleHint for the list of available hints.
  
      \sa setStyleHint(), QFont::StyleStrategy QFontInfo::styleHint()
  */
  QFont::StyleHint QFont::styleHint() const
  {
      return (StyleHint) d->request.styleHint;
  }
  
  /*!
      \enum QFont::StyleHint
  
      Style hints are used by the \l{QFont}{font matching} algorithm to
      find an appropriate default family if a selected font family is
      not available.
  
      \value AnyStyle leaves the font matching algorithm to choose the
             family. This is the default.
  
      \value SansSerif the font matcher prefer sans serif fonts.
      \value Helvetica is a synonym for \c SansSerif.
  
      \value Serif the font matcher prefers serif fonts.
      \value Times is a synonym for \c Serif.
  
      \value TypeWriter the font matcher prefers fixed pitch fonts.
      \value Courier a synonym for \c TypeWriter.
  
      \value OldEnglish the font matcher prefers decorative fonts.
      \value Decorative is a synonym for \c OldEnglish.
  
      \value Monospace the font matcher prefers fonts that map to the
      CSS generic font-family 'monospace'.
  
      \value Fantasy the font matcher prefers fonts that map to the
      CSS generic font-family 'fantasy'.
  
      \value Cursive the font matcher prefers fonts that map to the
      CSS generic font-family 'cursive'.
  
      \value System the font matcher prefers system fonts.
  */
  
  /*!
      \enum QFont::StyleStrategy
  
      The style strategy tells the \l{QFont}{font matching} algorithm
      what type of fonts should be used to find an appropriate default
      family.
  
      The following strategies are available:
  
      \value PreferDefault the default style strategy. It does not prefer
             any type of font.
      \value PreferBitmap prefers bitmap fonts (as opposed to outline
             fonts).
      \value PreferDevice prefers device fonts.
      \value PreferOutline prefers outline fonts (as opposed to bitmap fonts).
      \value ForceOutline forces the use of outline fonts.
      \value NoAntialias don't antialias the fonts.
      \value PreferAntialias antialias if possible.
      \value OpenGLCompatible forces the use of OpenGL compatible
             fonts.
      \value NoFontMerging If the font selected for a certain writing system
             does not contain a character requested to draw, then Qt automatically chooses a similar
             looking font that contains the character. The NoFontMerging flag disables this feature.
             Please note that enabling this flag will not prevent Qt from automatically picking a
             suitable font when the selected font does not support the writing system of the text.
  
      Any of these may be OR-ed with one of these flags:
  
      \value PreferMatch prefer an exact match. The font matcher will try to
             use the exact font size that has been specified.
      \value PreferQuality prefer the best quality font. The font matcher
             will use the nearest standard point size that the font
             supports.
      \value ForceIntegerMetrics forces the use of integer values in font engines that support fractional
             font metrics.
  */
  
  /*!
      Sets the style hint and strategy to \a hint and \a strategy,
      respectively.
  
      If these aren't set explicitly the style hint will default to
      \c AnyStyle and the style strategy to \c PreferDefault.
  
      Qt does not support style hints on X11 since this information
      is not provided by the window system.
  
      \sa StyleHint, styleHint(), StyleStrategy, styleStrategy(), QFontInfo
  */
  void QFont::setStyleHint(StyleHint hint, StyleStrategy strategy)
  {
      detach();
  
      if ((resolve_mask & (QFont::StyleHintResolved | QFont::StyleStrategyResolved)) &&
           (StyleHint) d->request.styleHint == hint &&
           (StyleStrategy) d->request.styleStrategy == strategy)
          return;
  
      d->request.styleHint = hint;
      d->request.styleStrategy = strategy;
      resolve_mask |= QFont::StyleHintResolved;
      resolve_mask |= QFont::StyleStrategyResolved;
  
  #if defined(Q_WS_X11)
      d->request.addStyle.clear();
  #endif // Q_WS_X11
  }
  
  /*!
      Sets the style strategy for the font to \a s.
  
      \sa QFont::StyleStrategy
  */
  void QFont::setStyleStrategy(StyleStrategy s)
  {
      detach();
  
      if ((resolve_mask & QFont::StyleStrategyResolved) &&
           s == (StyleStrategy)d->request.styleStrategy)
          return;
  
      d->request.styleStrategy = s;
      resolve_mask |= QFont::StyleStrategyResolved;
  }
  
  
  /*!
      \enum QFont::Stretch
  
      Predefined stretch values that follow the CSS naming convention. The higher
      the value, the more stretched the text is.
  
      \value UltraCondensed 50
      \value ExtraCondensed 62
      \value Condensed 75
      \value SemiCondensed 87
      \value Unstretched 100
      \value SemiExpanded 112
      \value Expanded 125
      \value ExtraExpanded 150
      \value UltraExpanded 200
  
      \sa setStretch() stretch()
  */
  
  /*!
      Returns the stretch factor for the font.
  
      \sa setStretch()
   */
  int QFont::stretch() const
  {
      return d->request.stretch;
  }
  
  /*!
      Sets the stretch factor for the font.
  
      The stretch factor changes the width of all characters in the font
      by \a factor percent.  For example, setting \a factor to 150
      results in all characters in the font being 1.5 times (ie. 150%)
      wider.  The default stretch factor is 100.  The minimum stretch
      factor is 1, and the maximum stretch factor is 4000.
  
      The stretch factor is only applied to outline fonts.  The stretch
      factor is ignored for bitmap fonts.
  
      NOTE: QFont cannot stretch XLFD fonts.  When loading XLFD fonts on
      X11, the stretch factor is matched against a predefined set of
      values for the SETWIDTH_NAME field of the XLFD.
  
      \sa stretch() QFont::Stretch
  */
  void QFont::setStretch(int factor)
  {
      if (factor < 1 || factor > 4000) {
          qWarning("QFont::setStretch: Parameter '%d' out of range", factor);
          return;
      }
  
      if ((resolve_mask & QFont::StretchResolved) &&
           d->request.stretch == (uint)factor)
          return;
  
      detach();
  
      d->request.stretch = (uint)factor;
      resolve_mask |= QFont::StretchResolved;
  }
  
  /*!
      \enum QFont::SpacingType
      \since 4.4
  
      \value PercentageSpacing  A value of 100 will keep the spacing unchanged; a value of 200 will enlarge the
                                                     spacing after a character by the width of the character itself.
      \value AbsoluteSpacing      A positive value increases the letter spacing by the corresponding pixels; a negative
                                                     value decreases the spacing.
  */
  
  /*!
      \since 4.4
      Returns the letter spacing for the font.
  
      \sa setLetterSpacing(), letterSpacingType(), setWordSpacing()
   */
  qreal QFont::letterSpacing() const
  {
      return d->letterSpacing.toReal();
  }
  
  /*!
      \since 4.4
      Sets the letter spacing for the font to \a spacing and the type
      of spacing to \a type.
  
      Letter spacing changes the default spacing between individual
      letters in the font.  The spacing between the letters can be
      made smaller as well as larger.
  
      \sa letterSpacing(), letterSpacingType(), setWordSpacing()
  */
  void QFont::setLetterSpacing(SpacingType type, qreal spacing)
  {
      const QFixed newSpacing = QFixed::fromReal(spacing);
      const bool absoluteSpacing = type == AbsoluteSpacing;
      if ((resolve_mask & QFont::LetterSpacingResolved) &&
          d->letterSpacingIsAbsolute == absoluteSpacing &&
          d->letterSpacing == newSpacing)
          return;
  
      detach();
  
      d->letterSpacing = newSpacing;
      d->letterSpacingIsAbsolute = absoluteSpacing;
      resolve_mask |= QFont::LetterSpacingResolved;
  }
  
  /*!
      \since 4.4
      Returns the spacing type used for letter spacing.
  
      \sa letterSpacing(), setLetterSpacing(), setWordSpacing()
  */
  QFont::SpacingType QFont::letterSpacingType() const
  {
      return d->letterSpacingIsAbsolute ? AbsoluteSpacing : PercentageSpacing;
  }
  
  /*!
      \since 4.4
      Returns the word spacing for the font.
  
      \sa setWordSpacing(), setLetterSpacing()
   */
  qreal QFont::wordSpacing() const
  {
      return d->wordSpacing.toReal();
  }
  
  /*!
      \since 4.4
      Sets the word spacing for the font to \a spacing.
  
      Word spacing changes the default spacing between individual
      words. A positive value increases the word spacing
      by a corresponding amount of pixels, while a negative value
      decreases the inter-word spacing accordingly.
  
      Word spacing will not apply to writing systems, where indiviaul
      words are not separated by white space.
  
      \sa wordSpacing(), setLetterSpacing()
  */
  void QFont::setWordSpacing(qreal spacing)
  {
      const QFixed newSpacing = QFixed::fromReal(spacing);
      if ((resolve_mask & QFont::WordSpacingResolved) &&
          d->wordSpacing == newSpacing)
          return;
  
      detach();
  
      d->wordSpacing = newSpacing;
      resolve_mask |= QFont::WordSpacingResolved;
  }
  
  /*!
      \enum QFont::Capitalization
      \since 4.4
  
      Rendering option for text this font applies to.
  
  
      \value MixedCase    This is the normal text rendering option where no capitalization change is applied.
      \value AllUppercase This alters the text to be rendered in all uppercase type.
      \value AllLowercase This alters the text to be rendered in all lowercase type.
      \value SmallCaps    This alters the text to be rendered in small-caps type.
      \value Capitalize   This alters the text to be rendered with the first character of each word as an uppercase character.
  */
  
  /*!
      \since 4.4
      Sets the capitalization of the text in this font to \a caps.
  
      A font's capitalization makes the text appear in the selected capitalization mode.
  
      \sa capitalization()
  */
  void QFont::setCapitalization(Capitalization caps)
  {
      if ((resolve_mask & QFont::CapitalizationResolved) &&
          capitalization() == caps)
          return;
  
      detach();
  
      d->capital = caps;
      resolve_mask |= QFont::CapitalizationResolved;
  }
  
  /*!
      \since 4.4
      Returns the current capitalization type of the font.
  
      \sa setCapitalization()
  */
  QFont::Capitalization QFont::capitalization() const
  {
      return static_cast<QFont::Capitalization> (d->capital);
  }
  
  
  /*!
      If \a enable is true, turns raw mode on; otherwise turns raw mode
      off. This function only has an effect under X11.
  
      If raw mode is enabled, Qt will search for an X font with a
      complete font name matching the family name, ignoring all other
      values set for the QFont. If the font name matches several fonts,
      Qt will use the first font returned by X. QFontInfo \e cannot be
      used to fetch information about a QFont using raw mode (it will
      return the values set in the QFont for all parameters, including
      the family name).
  
      \warning Do not use raw mode unless you really, really need it! In
      most (if not all) cases, setRawName() is a much better choice.
  
      \sa rawMode(), setRawName()
  */
  void QFont::setRawMode(bool enable)
  {
      detach();
  
      if ((bool) d->rawMode == enable) return;
  
      d->rawMode = enable;
  }
  
  /*!
      Returns true if a window system font exactly matching the settings
      of this font is available.
  
      \sa QFontInfo
  */
  bool QFont::exactMatch() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return (d->rawMode
              ? engine->type() != QFontEngine::Box
              : d->request.exactMatch(engine->fontDef));
  }
  
  /*!
      Returns true if this font is equal to \a f; otherwise returns
      false.
  
      Two QFonts are considered equal if their font attributes are
      equal. If rawMode() is enabled for both fonts, only the family
      fields are compared.
  
      \sa operator!=() isCopyOf()
  */
  bool QFont::operator==(const QFont &f) const
  {
      return (f.d == d
              || (f.d->request   == d->request
                  && f.d->request.pointSize == d->request.pointSize
                  && f.d->underline == d->underline
                  && f.d->overline  == d->overline
                  && f.d->strikeOut == d->strikeOut
                  && f.d->kerning == d->kerning
                  && f.d->capital == d->capital
                  && f.d->letterSpacingIsAbsolute == d->letterSpacingIsAbsolute
                  && f.d->letterSpacing == d->letterSpacing
                  && f.d->wordSpacing == d->wordSpacing
              ));
  }
  
  
  /*!
      Provides an arbitrary comparison of this font and font \a f.
      All that is guaranteed is that the operator returns false if both
      fonts are equal and that (f1 \< f2) == !(f2 \< f1) if the fonts
      are not equal.
  
      This function is useful in some circumstances, for example if you
      want to use QFont objects as keys in a QMap.
  
      \sa operator==() operator!=() isCopyOf()
  */
  bool QFont::operator<(const QFont &f) const
  {
      if (f.d == d) return false;
      // the < operator for fontdefs ignores point sizes.
      QFontDef &r1 = f.d->request;
      QFontDef &r2 = d->request;
      if (r1.pointSize != r2.pointSize) return r1.pointSize < r2.pointSize;
      if (r1.pixelSize != r2.pixelSize) return r1.pixelSize < r2.pixelSize;
      if (r1.weight != r2.weight) return r1.weight < r2.weight;
      if (r1.style != r2.style) return r1.style < r2.style;
      if (r1.stretch != r2.stretch) return r1.stretch < r2.stretch;
      if (r1.styleHint != r2.styleHint) return r1.styleHint < r2.styleHint;
      if (r1.styleStrategy != r2.styleStrategy) return r1.styleStrategy < r2.styleStrategy;
      if (r1.family != r2.family) return r1.family < r2.family;
  #ifdef Q_WS_X11
      if (r1.addStyle != r2.addStyle) return r1.addStyle < r2.addStyle;
  #endif // Q_WS_X11
      if (f.d->capital != d->capital) return f.d->capital < d->capital;
  
      if (f.d->letterSpacingIsAbsolute != d->letterSpacingIsAbsolute) return f.d->letterSpacingIsAbsolute < d->letterSpacingIsAbsolute;
      if (f.d->letterSpacing != d->letterSpacing) return f.d->letterSpacing < d->letterSpacing;
      if (f.d->wordSpacing != d->wordSpacing) return f.d->wordSpacing < d->wordSpacing;
  
      int f1attrs = (f.d->underline << 3) + (f.d->overline << 2) + (f.d->strikeOut<<1) + f.d->kerning;
      int f2attrs = (d->underline << 3) + (d->overline << 2) + (d->strikeOut<<1) + d->kerning;
      return f1attrs < f2attrs;
  }
  
  
  /*!
      Returns true if this font is different from \a f; otherwise
      returns false.
  
      Two QFonts are considered to be different if their font attributes
      are different. If rawMode() is enabled for both fonts, only the
      family fields are compared.
  
      \sa operator==()
  */
  bool QFont::operator!=(const QFont &f) const
  {
      return !(operator==(f));
  }
  
  /*!
     Returns the font as a QVariant
  */
  QFont::operator QVariant() const
  {
      return QVariant(QVariant::Font, this);
  }
  
  /*!
      Returns true if this font and \a f are copies of each other, i.e.
      one of them was created as a copy of the other and neither has
      been modified since. This is much stricter than equality.
  
      \sa operator=() operator==()
  */
  bool QFont::isCopyOf(const QFont & f) const
  {
      return d == f.d;
  }
  
  /*!
      Returns true if raw mode is used for font name matching; otherwise
      returns false.
  
      \sa setRawMode() rawName()
  */
  bool QFont::rawMode() const
  {
      return d->rawMode;
  }
  
  /*!
      Returns a new QFont that has attributes copied from \a other that
      have not been previously set on this font.
  */
  QFont QFont::resolve(const QFont &other) const
  {
      if (*this == other
          && (resolve_mask == other.resolve_mask || resolve_mask == 0)
          && d->dpi == other.d->dpi) {
          QFont o = other;
          o.resolve_mask = resolve_mask;
          return o;
      }
  
      QFont font(*this);
      font.detach();
      font.d->resolve(resolve_mask, other.d.data());
  
      return font;
  }
  
  /*!
      \fn uint QFont::resolve() const
      \internal
  */
  
  /*!
      \fn void QFont::resolve(uint mask)
      \internal
  */
  
  #ifdef QT3_SUPPORT
  
  /*! \obsolete
  
    Please use QApplication::font() instead.
  */
  QFont QFont::defaultFont()
  {
      return QApplication::font();
  }
  
  /*! \obsolete
  
    Please use QApplication::setFont() instead.
  */
  void QFont::setDefaultFont(const QFont &f)
  {
      QApplication::setFont(f);
  }
  
  /*!
      \fn qreal QFont::pointSizeFloat() const
      \compat
  
      Use pointSizeF() instead.
  */
  
  /*!
      \fn void QFont::setPointSizeFloat(qreal size)
      \compat
  
      Use setPointSizeF() instead.
  */
  #endif
  
  
  
  
  /*****************************************************************************
    QFont substitution management
   *****************************************************************************/
  
  typedef QHash<QString, QStringList> QFontSubst;
  Q_GLOBAL_STATIC(QFontSubst, globalFontSubst)
  
  // create substitution dict
  static void initFontSubst()
  {
      // default substitutions
      static const char * const initTbl[] = {
  
  #if defined(Q_WS_X11)
          "arial",        "helvetica",
          "times new roman", "times",
          "courier new",  "courier",
          "sans serif",   "helvetica",
  #elif defined(Q_WS_WIN)
          "times",        "times new roman",
          "courier",      "courier new",
          "helvetica",    "arial",
          "sans serif",   "arial",
  #endif
  
          0,              0
      };
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      if (!fontSubst->isEmpty())
          return;
  #if defined(Q_WS_X11) && !defined(QT_NO_FONTCONFIG)
      if (X11->has_fontconfig)
          return;
  #endif
  
      for (int i=0; initTbl[i] != 0; i += 2) {
          QStringList &list = (*fontSubst)[QString::fromLatin1(initTbl[i])];
          list.append(QString::fromLatin1(initTbl[i+1]));
      }
  }
  
  /*!
      Returns the first family name to be used whenever \a familyName is
      specified. The lookup is case insensitive.
  
      If there is no substitution for \a familyName, \a familyName is
      returned.
  
      To obtain a list of substitutions use substitutes().
  
      \sa setFamily() insertSubstitutions() insertSubstitution() removeSubstitution()
  */
  QString QFont::substitute(const QString &familyName)
  {
      initFontSubst();
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      QFontSubst::ConstIterator it = fontSubst->constFind(familyName.toLower());
      if (it != fontSubst->constEnd() && !(*it).isEmpty())
          return (*it).first();
  
      return familyName;
  }
  
  
  /*!
      Returns a list of family names to be used whenever \a familyName
      is specified. The lookup is case insensitive.
  
      If there is no substitution for \a familyName, an empty list is
      returned.
  
      \sa substitute() insertSubstitutions() insertSubstitution() removeSubstitution()
   */
  QStringList QFont::substitutes(const QString &familyName)
  {
      initFontSubst();
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      return fontSubst->value(familyName.toLower(), QStringList());
  }
  
  
  /*!
      Inserts \a substituteName into the substitution
      table for the family \a familyName.
  
      \sa insertSubstitutions() removeSubstitution() substitutions() substitute() substitutes()
  */
  void QFont::insertSubstitution(const QString &familyName,
                                 const QString &substituteName)
  {
      initFontSubst();
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      QStringList &list = (*fontSubst)[familyName.toLower()];
      QString s = substituteName.toLower();
      if (!list.contains(s))
          list.append(s);
  }
  
  
  /*!
      Inserts the list of families \a substituteNames into the
      substitution list for \a familyName.
  
      \sa insertSubstitution(), removeSubstitution(), substitutions(), substitute()
  */
  void QFont::insertSubstitutions(const QString &familyName,
                                  const QStringList &substituteNames)
  {
      initFontSubst();
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      QStringList &list = (*fontSubst)[familyName.toLower()];
      QStringList::ConstIterator it = substituteNames.constBegin();
      while (it != substituteNames.constEnd()) {
          QString s = (*it).toLower();
          if (!list.contains(s))
              list.append(s);
          it++;
      }
  }
  
  /*! \fn void QFont::initialize()
    \internal
  
    Internal function that initializes the font system.  The font cache
    and font dict do not alloc the keys. The key is a QString which is
    shared between QFontPrivate and QXFontName.
  */
  
  /*! \fn void QFont::cleanup()
    \internal
  
    Internal function that cleans up the font system.
  */
  
  // ### mark: should be called removeSubstitutions()
  /*!
      Removes all the substitutions for \a familyName.
  
      \sa insertSubstitutions(), insertSubstitution(), substitutions(), substitute()
  */
  void QFont::removeSubstitution(const QString &familyName)
  { // ### function name should be removeSubstitutions() or
    // ### removeSubstitutionList()
      initFontSubst();
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      fontSubst->remove(familyName.toLower());
  }
  
  
  /*!
      Returns a sorted list of substituted family names.
  
      \sa insertSubstitution(), removeSubstitution(), substitute()
  */
  QStringList QFont::substitutions()
  {
      initFontSubst();
  
      QFontSubst *fontSubst = globalFontSubst();
      Q_ASSERT(fontSubst != 0);
      QStringList ret;
      QFontSubst::ConstIterator it = fontSubst->constBegin();
  
      while (it != fontSubst->constEnd()) {
          ret.append(it.key());
          ++it;
      }
  
      ret.sort();
      return ret;
  }
  
  
  /*  \internal
      Internal function. Converts boolean font settings to an unsigned
      8-bit number. Used for serialization etc.
  */
  static quint8 get_font_bits(int version, const QFontPrivate *f)
  {
      Q_ASSERT(f != 0);
      quint8 bits = 0;
      if (f->request.style)
          bits |= 0x01;
      if (f->underline)
          bits |= 0x02;
      if (f->overline)
          bits |= 0x40;
      if (f->strikeOut)
          bits |= 0x04;
      if (f->request.fixedPitch)
          bits |= 0x08;
      // if (f.hintSetByUser)
      // bits |= 0x10;
      if (f->rawMode)
          bits |= 0x20;
      if (version >= QDataStream::Qt_4_0) {
          if (f->kerning)
              bits |= 0x10;
      }
      if (f->request.style == QFont::StyleOblique)
          bits |= 0x80;
      return bits;
  }
  
  static quint8 get_extended_font_bits(const QFontPrivate *f)
  {
      Q_ASSERT(f != 0);
      quint8 bits = 0;
      if (f->request.ignorePitch)
          bits |= 0x01;
      if (f->letterSpacingIsAbsolute)
          bits |= 0x02;
      return bits;
  }
  
  #ifndef QT_NO_DATASTREAM
  
  /*  \internal
      Internal function. Sets boolean font settings from an unsigned
      8-bit number. Used for serialization etc.
  */
  static void set_font_bits(int version, quint8 bits, QFontPrivate *f)
  {
      Q_ASSERT(f != 0);
      f->request.style         = (bits & 0x01) != 0 ? QFont::StyleItalic : QFont::StyleNormal;
      f->underline             = (bits & 0x02) != 0;
      f->overline              = (bits & 0x40) != 0;
      f->strikeOut             = (bits & 0x04) != 0;
      f->request.fixedPitch    = (bits & 0x08) != 0;
      // f->hintSetByUser      = (bits & 0x10) != 0;
      f->rawMode               = (bits & 0x20) != 0;
      if (version >= QDataStream::Qt_4_0)
          f->kerning               = (bits & 0x10) != 0;
      if ((bits & 0x80) != 0)
          f->request.style         = QFont::StyleOblique;
  }
  
  static void set_extended_font_bits(quint8 bits, QFontPrivate *f)
  {
      Q_ASSERT(f != 0);
      f->request.ignorePitch = (bits & 0x01) != 0;
      f->letterSpacingIsAbsolute = (bits & 0x02) != 0;
  }
  #endif
  
  
  /*!
      Returns the font's key, a textual representation of a font. It is
      typically used as the key for a cache or dictionary of fonts.
  
      \sa QMap
  */
  QString QFont::key() const
  {
      return toString();
  }
  
  /*!
      Returns a description of the font. The description is a
      comma-separated list of the attributes, perfectly suited for use
      in QSettings.
  
      \sa fromString()
   */
  QString QFont::toString() const
  {
      const QChar comma(QLatin1Char(','));
      return family() + comma +
          QString::number(     pointSizeF()) + comma +
          QString::number(      pixelSize()) + comma +
          QString::number((int) styleHint()) + comma +
          QString::number(         weight()) + comma +
          QString::number((int)     style()) + comma +
          QString::number((int) underline()) + comma +
          QString::number((int) strikeOut()) + comma +
          QString::number((int)fixedPitch()) + comma +
          QString::number((int)   rawMode());
  }
  
  
  /*!
      Sets this font to match the description \a descrip. The description
      is a comma-separated list of the font attributes, as returned by
      toString().
  
      \sa toString()
   */
  bool QFont::fromString(const QString &descrip)
  {
      QStringList l(descrip.split(QLatin1Char(',')));
  
      int count = l.count();
      if (!count || (count > 2 && count < 9) || count > 11) {
          qWarning("QFont::fromString: Invalid description '%s'",
                   descrip.isEmpty() ? "(empty)" : descrip.toLatin1().data());
          return false;
      }
  
      setFamily(l[0]);
      if (count > 1 && l[1].toDouble() > 0.0)
          setPointSizeF(l[1].toDouble());
      if (count == 9) {
          setStyleHint((StyleHint) l[2].toInt());
          setWeight(qMax(qMin(99, l[3].toInt()), 0));
          setItalic(l[4].toInt());
          setUnderline(l[5].toInt());
          setStrikeOut(l[6].toInt());
          setFixedPitch(l[7].toInt());
          setRawMode(l[8].toInt());
      } else if (count == 10) {
          if (l[2].toInt() > 0)
              setPixelSize(l[2].toInt());
          setStyleHint((StyleHint) l[3].toInt());
          setWeight(qMax(qMin(99, l[4].toInt()), 0));
          setStyle((QFont::Style)l[5].toInt());
          setUnderline(l[6].toInt());
          setStrikeOut(l[7].toInt());
          setFixedPitch(l[8].toInt());
          setRawMode(l[9].toInt());
      }
      if (count >= 9 && !d->request.fixedPitch) // assume 'false' fixedPitch equals default
          d->request.ignorePitch = true;
  
      return true;
  }
  
  #if !defined(Q_WS_QWS)
  /*! \internal
  
    Internal function that dumps font cache statistics.
  */
  void QFont::cacheStatistics()
  {
  
  
  }
  #endif // !Q_WS_QWS
  
  
  
  /*****************************************************************************
    QFont stream functions
   *****************************************************************************/
  #ifndef QT_NO_DATASTREAM
  
  /*!
      \relates QFont
  
      Writes the font \a font to the data stream \a s. (toString()
      writes to a text stream.)
  
      \sa \link datastreamformat.html Format of the QDataStream operators \endlink
  */
  QDataStream &operator<<(QDataStream &s, const QFont &font)
  {
      if (s.version() == 1) {
          s << font.d->request.family.toLatin1();
      } else {
          s << font.d->request.family;
      }
  
      if (s.version() >= QDataStream::Qt_4_0) {
          // 4.0
          double pointSize = font.d->request.pointSize;
          qint32 pixelSize = font.d->request.pixelSize;
          s << pointSize;
          s << pixelSize;
      } else if (s.version() <= 3) {
          qint16 pointSize = (qint16) (font.d->request.pointSize * 10);
          if (pointSize < 0) {
  #ifdef Q_WS_X11
              pointSize = (qint16)(font.d->request.pixelSize*720/QX11Info::appDpiY());
  #else
              pointSize = (qint16)QFontInfo(font).pointSize() * 10;
  #endif
          }
          s << pointSize;
      } else {
          s << (qint16) (font.d->request.pointSize * 10);
          s << (qint16) font.d->request.pixelSize;
      }
  
      s << (quint8) font.d->request.styleHint;
      if (s.version() >= QDataStream::Qt_3_1)
          s << (quint8) font.d->request.styleStrategy;
      s << (quint8) 0
        << (quint8) font.d->request.weight
        << get_font_bits(s.version(), font.d.data());
      if (s.version() >= QDataStream::Qt_4_3)
          s << (quint16)font.d->request.stretch;
      if (s.version() >= QDataStream::Qt_4_4)
          s << get_extended_font_bits(font.d.data());
      if (s.version() >= QDataStream::Qt_4_5) {
          s << font.d->letterSpacing.value();
          s << font.d->wordSpacing.value();
      }
      return s;
  }
  
  
  /*!
      \relates QFont
  
      Reads the font \a font from the data stream \a s. (fromString()
      reads from a text stream.)
  
      \sa \link datastreamformat.html Format of the QDataStream operators \endlink
  */
  QDataStream &operator>>(QDataStream &s, QFont &font)
  {
      font.d = new QFontPrivate;
      font.resolve_mask = QFont::AllPropertiesResolved;
  
      quint8 styleHint, styleStrategy = QFont::PreferDefault, charSet, weight, bits;
  
      if (s.version() == 1) {
          QByteArray fam;
          s >> fam;
          font.d->request.family = QString::fromLatin1(fam);
      } else {
          s >> font.d->request.family;
      }
  
      if (s.version() >= QDataStream::Qt_4_0) {
          // 4.0
          double pointSize;
          qint32 pixelSize;
          s >> pointSize;
          s >> pixelSize;
          font.d->request.pointSize = qreal(pointSize);
          font.d->request.pixelSize = pixelSize;
      } else {
          qint16 pointSize, pixelSize = -1;
          s >> pointSize;
          if (s.version() >= 4)
              s >> pixelSize;
          font.d->request.pointSize = qreal(pointSize / 10.);
          font.d->request.pixelSize = pixelSize;
      }
      s >> styleHint;
      if (s.version() >= QDataStream::Qt_3_1)
          s >> styleStrategy;
  
      s >> charSet;
      s >> weight;
      s >> bits;
  
      font.d->request.styleHint = styleHint;
      font.d->request.styleStrategy = styleStrategy;
      font.d->request.weight = weight;
  
      set_font_bits(s.version(), bits, font.d.data());
  
      if (s.version() >= QDataStream::Qt_4_3) {
          quint16 stretch;
          s >> stretch;
          font.d->request.stretch = stretch;
      }
  
      if (s.version() >= QDataStream::Qt_4_4) {
          quint8 extendedBits;
          s >> extendedBits;
          set_extended_font_bits(extendedBits, font.d.data());
      }
      if (s.version() >= QDataStream::Qt_4_5) {
          int value;
          s >> value;
          font.d->letterSpacing.setValue(value);
          s >> value;
          font.d->wordSpacing.setValue(value);
      }
  
      return s;
  }
  
  #endif // QT_NO_DATASTREAM
  
  
  /*****************************************************************************
    QFontInfo member functions
   *****************************************************************************/
  
  /*!
      \class QFontInfo
      \reentrant
  
      \brief The QFontInfo class provides general information about fonts.
  
      \ingroup appearance
      \ingroup shared
  
      The QFontInfo class provides the same access functions as QFont,
      e.g. family(), pointSize(), italic(), weight(), fixedPitch(),
      styleHint() etc. But whilst the QFont access functions return the
      values that were set, a QFontInfo object returns the values that
      apply to the font that will actually be used to draw the text.
  
      For example, when the program asks for a 25pt Courier font on a
      machine that has a non-scalable 24pt Courier font, QFont will
      (normally) use the 24pt Courier for rendering. In this case,
      QFont::pointSize() returns 25 and QFontInfo::pointSize() returns
      24.
  
      There are three ways to create a QFontInfo object.
      \list 1
      \o Calling the QFontInfo constructor with a QFont creates a font
      info object for a screen-compatible font, i.e. the font cannot be
      a printer font. If the font is changed later, the font
      info object is \e not updated.
  
      (Note: If you use a printer font the values returned may be
      inaccurate. Printer fonts are not always accessible so the nearest
      screen font is used if a printer font is supplied.)
  
      \o QWidget::fontInfo() returns the font info for a widget's font.
      This is equivalent to calling QFontInfo(widget->font()). If the
      widget's font is changed later, the font info object is \e not
      updated.
  
      \o QPainter::fontInfo() returns the font info for a painter's
      current font. If the painter's font is changed later, the font
      info object is \e not updated.
      \endlist
  
      \sa QFont QFontMetrics QFontDatabase
  */
  
  /*!
      Constructs a font info object for \a font.
  
      The font must be screen-compatible, i.e. a font you use when
      drawing text in \link QWidget widgets\endlink or \link QPixmap
      pixmaps\endlink, not QPicture or QPrinter.
  
      The font info object holds the information for the font that is
      passed in the constructor at the time it is created, and is not
      updated if the font's attributes are changed later.
  
      Use QPainter::fontInfo() to get the font info when painting.
      This will give correct results also when painting on paint device
      that is not screen-compatible.
  */
  QFontInfo::QFontInfo(const QFont &font)
      : d(font.d.data())
  {
  }
  
  /*!
      Constructs a copy of \a fi.
  */
  QFontInfo::QFontInfo(const QFontInfo &fi)
      : d(fi.d.data())
  {
  }
  
  /*!
      Destroys the font info object.
  */
  QFontInfo::~QFontInfo()
  {
  }
  
  /*!
      Assigns the font info in \a fi.
  */
  QFontInfo &QFontInfo::operator=(const QFontInfo &fi)
  {
      d = fi.d.data();
      return *this;
  }
  
  /*!
      Returns the family name of the matched window system font.
  
      \sa QFont::family()
  */
  QString QFontInfo::family() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return engine->fontDef.family;
  }
  
  /*!
      \since 4.8
  
      Returns the style name of the matched window system font on
      system that supports it.
  
      \sa QFont::styleName()
  */
  QString QFontInfo::styleName() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return engine->fontDef.styleName;
  }
  
  /*!
      Returns the point size of the matched window system font.
  
      \sa pointSizeF() QFont::pointSize()
  */
  int QFontInfo::pointSize() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return qRound(engine->fontDef.pointSize);
  }
  
  /*!
      Returns the point size of the matched window system font.
  
      \sa QFont::pointSizeF()
  */
  qreal QFontInfo::pointSizeF() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return engine->fontDef.pointSize;
  }
  
  /*!
      Returns the pixel size of the matched window system font.
  
      \sa QFont::pointSize()
  */
  int QFontInfo::pixelSize() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return engine->fontDef.pixelSize;
  }
  
  /*!
      Returns the italic value of the matched window system font.
  
      \sa QFont::italic()
  */
  bool QFontInfo::italic() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return engine->fontDef.style != QFont::StyleNormal;
  }
  
  /*!
      Returns the style value of the matched window system font.
  
      \sa QFont::style()
  */
  QFont::Style QFontInfo::style() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return (QFont::Style)engine->fontDef.style;
  }
  
  /*!
      Returns the weight of the matched window system font.
  
      \sa QFont::weight(), bold()
  */
  int QFontInfo::weight() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return engine->fontDef.weight;
  
  }
  
  /*!
      \fn bool QFontInfo::bold() const
  
      Returns true if weight() would return a value greater than
      QFont::Normal; otherwise returns false.
  
      \sa weight(), QFont::bold()
  */
  
  /*!
      Returns the underline value of the matched window system font.
  
    \sa QFont::underline()
  
    \internal
  
    Here we read the underline flag directly from the QFont.
    This is OK for X11 and for Windows because we always get what we want.
  */
  bool QFontInfo::underline() const
  {
      return d->underline;
  }
  
  /*!
      Returns the overline value of the matched window system font.
  
      \sa QFont::overline()
  
      \internal
  
      Here we read the overline flag directly from the QFont.
      This is OK for X11 and for Windows because we always get what we want.
  */
  bool QFontInfo::overline() const
  {
      return d->overline;
  }
  
  /*!
      Returns the strikeout value of the matched window system font.
  
    \sa QFont::strikeOut()
  
    \internal Here we read the strikeOut flag directly from the QFont.
    This is OK for X11 and for Windows because we always get what we want.
  */
  bool QFontInfo::strikeOut() const
  {
      return d->strikeOut;
  }
  
  /*!
      Returns the fixed pitch value of the matched window system font.
  
      \sa QFont::fixedPitch()
  */
  bool QFontInfo::fixedPitch() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
  #ifdef Q_OS_MAC
      if (!engine->fontDef.fixedPitchComputed) {
          QChar ch[2] = { QLatin1Char('i'), QLatin1Char('m') };
          QGlyphLayoutArray<2> g;
          int l = 2;
          engine->stringToCMap(ch, 2, &g, &l, 0);
          engine->fontDef.fixedPitch = g.advances_x[0] == g.advances_x[1];
          engine->fontDef.fixedPitchComputed = true;
      }
  #endif
      return engine->fontDef.fixedPitch;
  }
  
  /*!
      Returns the style of the matched window system font.
  
      Currently only returns the style hint set in QFont.
  
      \sa QFont::styleHint() QFont::StyleHint
  */
  QFont::StyleHint QFontInfo::styleHint() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return (QFont::StyleHint) engine->fontDef.styleHint;
  }
  
  /*!
      Returns true if the font is a raw mode font; otherwise returns
      false.
  
      If it is a raw mode font, all other functions in QFontInfo will
      return the same values set in the QFont, regardless of the font
      actually used.
  
      \sa QFont::rawMode()
  */
  bool QFontInfo::rawMode() const
  {
      return d->rawMode;
  }
  
  /*!
      Returns true if the matched window system font is exactly the same
      as the one specified by the font; otherwise returns false.
  
      \sa QFont::exactMatch()
  */
  bool QFontInfo::exactMatch() const
  {
      QFontEngine *engine = d->engineForScript(QUnicodeTables::Common);
      Q_ASSERT(engine != 0);
      return (d->rawMode
              ? engine->type() != QFontEngine::Box
              : d->request.exactMatch(engine->fontDef));
  }
  
  
  
  
  // **********************************************************************
  // QFontCache
  // **********************************************************************
  
  #ifdef QFONTCACHE_DEBUG
  // fast timeouts for debugging
  static const int fast_timeout =   1000;  // 1s
  static const int slow_timeout =   5000;  // 5s
  #else
  static const int fast_timeout =  10000; // 10s
  static const int slow_timeout = 300000; //  5m
  #endif // QFONTCACHE_DEBUG
  
  const uint QFontCache::min_cost = 4*1024; // 4mb
  
  #ifdef QT_NO_THREAD
  Q_GLOBAL_STATIC(QFontCache, theFontCache)
  
  QFontCache *QFontCache::instance()
  {
      return theFontCache();
  }
  
  void QFontCache::cleanup()
  {
  }
  #else
  Q_GLOBAL_STATIC(QThreadStorage<QFontCache *>, theFontCache)
  
  QFontCache *QFontCache::instance()
  {
      QFontCache *&fontCache = theFontCache()->localData();
      if (!fontCache)
          fontCache = new QFontCache;
      return fontCache;
  }
  
  void QFontCache::cleanup()
  {
      QThreadStorage<QFontCache *> *cache = 0;
      QT_TRY {
          cache = theFontCache();
      } QT_CATCH (const std::bad_alloc &) {
          // no cache - just ignore
      }
      if (cache && cache->hasLocalData())
          cache->setLocalData(0);
  }
  #endif // QT_NO_THREAD
  
  QFontCache::QFontCache()
      : QObject(), total_cost(0), max_cost(min_cost),
        current_timestamp(0), fast(false), timer_id(-1)
  {
  }
  
  QFontCache::~QFontCache()
  {
      clear();
      {
          EngineDataCache::ConstIterator it = engineDataCache.constBegin(),
                                   end = engineDataCache.constEnd();
          while (it != end) {
              if (it.value()->ref == 0)
                  delete it.value();
              else
                  FC_DEBUG("QFontCache::~QFontCache: engineData %p still has refcount %d",
                           it.value(), int(it.value()->ref));
              ++it;
          }
      }
      EngineCache::ConstIterator it = engineCache.constBegin(),
                           end = engineCache.constEnd();
      while (it != end) {
          if (--it.value().data->cache_count == 0) {
              if (it.value().data->ref == 0) {
                  FC_DEBUG("QFontCache::~QFontCache: deleting engine %p key=(%d / %g %g %d %d %d)",
                           it.value().data, it.key().script, it.key().def.pointSize,
                           it.key().def.pixelSize, it.key().def.weight, it.key().def.style,
                           it.key().def.fixedPitch);
  
                  delete it.value().data;
              } else {
                  FC_DEBUG("QFontCache::~QFontCache: engine = %p still has refcount %d",
                           it.value().data, int(it.value().data->ref));
              }
          }
          ++it;
      }
  }
  
  void QFontCache::clear()
  {
      {
          EngineDataCache::Iterator it = engineDataCache.begin(),
                                   end = engineDataCache.end();
          while (it != end) {
              QFontEngineData *data = it.value();
  #if !defined(Q_WS_MAC)
              for (int i = 0; i < QUnicodeTables::ScriptCount; ++i) {
                  if (data->engines[i]) {
                      data->engines[i]->ref.deref();
                      data->engines[i] = 0;
                  }
              }
  #else
              if (data->engine) {
                  data->engine->ref.deref();
                  data->engine = 0;
              }
  #endif
              ++it;
          }
      }
  
      for (EngineCache::Iterator it = engineCache.begin(), end = engineCache.end();
           it != end; ++it) {
          if (it->data->ref == 0) {
              delete it->data;
              it->data = 0;
          }
      }
  
      for (EngineCache::Iterator it = engineCache.begin(), end = engineCache.end();
           it != end; ++it) {
          if (it->data && it->data->ref == 0) {
              delete it->data;
              it->data = 0;
          }
      }
  
      engineCache.clear();
  }
  
  #if defined(Q_WS_QWS) && !defined(QT_NO_QWS_QPF2)
  void QFontCache::removeEngineForFont(const QByteArray &_fontName)
  {
  
      /* This could be optimized but the code becomes much more complex if we want to handle multi
       * font engines and it is probably not worth it. Therefore we just clear the entire font cache.
       */
      Q_UNUSED(_fontName);
      clear();
  }
  #endif
  
  QFontEngineData *QFontCache::findEngineData(const Key &key) const
  {
      EngineDataCache::ConstIterator it = engineDataCache.find(key),
                                    end = engineDataCache.end();
      if (it == end) return 0;
  
      // found
      return it.value();
  }
  
  void QFontCache::insertEngineData(const Key &key, QFontEngineData *engineData)
  {
      FC_DEBUG("QFontCache: inserting new engine data %p", engineData);
  
      engineDataCache.insert(key, engineData);
      increaseCost(sizeof(QFontEngineData));
  }
  
  QFontEngine *QFontCache::findEngine(const Key &key)
  {
      EngineCache::Iterator it = engineCache.find(key),
                           end = engineCache.end();
      if (it == end) return 0;
  
      // found... update the hitcount and timestamp
      it.value().hits++;
      it.value().timestamp = ++current_timestamp;
  
      FC_DEBUG("QFontCache: found font engine\n"
               "  %p: timestamp %4u hits %3u ref %2d/%2d, type '%s'",
               it.value().data, it.value().timestamp, it.value().hits,
               int(it.value().data->ref), it.value().data->cache_count,
               it.value().data->name());
  
      return it.value().data;
  }
  
  void QFontCache::insertEngine(const Key &key, QFontEngine *engine)
  {
      FC_DEBUG("QFontCache: inserting new engine %p", engine);
  
      Engine data(engine);
      data.timestamp = ++current_timestamp;
  
      engineCache.insert(key, data);
  
      // only increase the cost if this is the first time we insert the engine
      if (engine->cache_count == 0)
          increaseCost(engine->cache_cost);
  
      ++engine->cache_count;
  }
  
  void QFontCache::increaseCost(uint cost)
  {
      cost = (cost + 512) / 1024; // store cost in kb
      cost = cost > 0 ? cost : 1;
      total_cost += cost;
  
      FC_DEBUG("  COST: increased %u kb, total_cost %u kb, max_cost %u kb",
              cost, total_cost, max_cost);
  
      if (total_cost > max_cost) {
          max_cost = total_cost;
  
          if (timer_id == -1 || ! fast) {
              FC_DEBUG("  TIMER: starting fast timer (%d ms)", fast_timeout);
  
              if (timer_id != -1) killTimer(timer_id);
              timer_id = startTimer(fast_timeout);
              fast = true;
          }
      }
  }
  
  void QFontCache::decreaseCost(uint cost)
  {
      cost = (cost + 512) / 1024; // cost is stored in kb
      cost = cost > 0 ? cost : 1;
      Q_ASSERT(cost <= total_cost);
      total_cost -= cost;
  
      FC_DEBUG("  COST: decreased %u kb, total_cost %u kb, max_cost %u kb",
              cost, total_cost, max_cost);
  }
  
  #if defined(Q_WS_WIN) || defined (Q_WS_QWS)
  void QFontCache::cleanupPrinterFonts()
  {
      FC_DEBUG("QFontCache::cleanupPrinterFonts");
  
      {
          FC_DEBUG("  CLEAN engine data:");
  
          // clean out all unused engine data
          EngineDataCache::Iterator it = engineDataCache.begin(),
                                   end = engineDataCache.end();
          while (it != end) {
              if (it.key().screen == 0) {
                  ++it;
                  continue;
              }
  
              if(it.value()->ref != 0) {
                  for(int i = 0; i < QUnicodeTables::ScriptCount; ++i) {
                      if(it.value()->engines[i]) {
                          it.value()->engines[i]->ref.deref();
                          it.value()->engines[i] = 0;
                      }
                  }
                  ++it;
              } else {
  
                  EngineDataCache::Iterator rem = it++;
  
                  decreaseCost(sizeof(QFontEngineData));
  
                  FC_DEBUG("    %p", rem.value());
  
                  delete rem.value();
                  engineDataCache.erase(rem);
              }
          }
      }
  
      EngineCache::Iterator it = engineCache.begin(),
                           end = engineCache.end();
      while(it != end) {
          if (it.value().data->ref != 0 || it.key().screen == 0) {
              ++it;
              continue;
          }
  
          FC_DEBUG("    %p: timestamp %4u hits %2u ref %2d/%2d, type '%s'",
                   it.value().data, it.value().timestamp, it.value().hits,
                   int(it.value().data->ref), it.value().data->cache_count,
                   it.value().data->name());
  
          if (--it.value().data->cache_count == 0) {
              FC_DEBUG("    DELETE: last occurrence in cache");
  
              decreaseCost(it.value().data->cache_cost);
              delete it.value().data;
          }
  
          engineCache.erase(it++);
      }
  }
  #endif
  
  void QFontCache::timerEvent(QTimerEvent *)
  {
      FC_DEBUG("QFontCache::timerEvent: performing cache maintenance (timestamp %u)",
                current_timestamp);
  
      if (total_cost <= max_cost && max_cost <= min_cost) {
          FC_DEBUG("  cache redused sufficiently, stopping timer");
  
          killTimer(timer_id);
          timer_id = -1;
          fast = false;
  
          return;
      }
  
      // go through the cache and count up everything in use
      uint in_use_cost = 0;
  
      {
          FC_DEBUG("  SWEEP engine data:");
  
          // make sure the cost of each engine data is at least 1kb
          const uint engine_data_cost =
              sizeof(QFontEngineData) > 1024 ? sizeof(QFontEngineData) : 1024;
  
          EngineDataCache::ConstIterator it = engineDataCache.constBegin(),
                                        end = engineDataCache.constEnd();
          for (; it != end; ++it) {
  #ifdef QFONTCACHE_DEBUG
              FC_DEBUG("    %p: ref %2d", it.value(), int(it.value()->ref));
  
  #  if defined(Q_WS_X11) || defined(Q_WS_WIN)
              // print out all engines
              for (int i = 0; i < QUnicodeTables::ScriptCount; ++i) {
                  if (! it.value()->engines[i])
                      continue;
                  FC_DEBUG("      contains %p", it.value()->engines[i]);
              }
  #  endif // Q_WS_X11 || Q_WS_WIN
  #endif // QFONTCACHE_DEBUG
  
              if (it.value()->ref != 0)
                  in_use_cost += engine_data_cost;
          }
      }
  
      {
          FC_DEBUG("  SWEEP engine:");
  
          EngineCache::ConstIterator it = engineCache.constBegin(),
                                    end = engineCache.constEnd();
          for (; it != end; ++it) {
              FC_DEBUG("    %p: timestamp %4u hits %2u ref %2d/%2d, cost %u bytes",
                       it.value().data, it.value().timestamp, it.value().hits,
                       int(it.value().data->ref), it.value().data->cache_count,
                       it.value().data->cache_cost);
  
              if (it.value().data->ref != 0)
                  in_use_cost += it.value().data->cache_cost / it.value().data->cache_count;
          }
  
          // attempt to make up for rounding errors
          in_use_cost += engineCache.size();
      }
  
      in_use_cost = (in_use_cost + 512) / 1024; // cost is stored in kb
  
      /*
        calculate the new maximum cost for the cache
  
        NOTE: in_use_cost is *not* correct due to rounding errors in the
        above algorithm.  instead of worrying about getting the
        calculation correct, we are more interested in speed, and use
        in_use_cost as a floor for new_max_cost
      */
      uint new_max_cost = qMax(qMax(max_cost / 2, in_use_cost), min_cost);
  
      FC_DEBUG("  after sweep, in use %u kb, total %u kb, max %u kb, new max %u kb",
                in_use_cost, total_cost, max_cost, new_max_cost);
  
      if (new_max_cost == max_cost) {
          if (fast) {
              FC_DEBUG("  cannot shrink cache, slowing timer");
  
              killTimer(timer_id);
              timer_id = startTimer(slow_timeout);
              fast = false;
          }
  
          return;
      } else if (! fast) {
          FC_DEBUG("  dropping into passing gear");
  
          killTimer(timer_id);
          timer_id = startTimer(fast_timeout);
          fast = true;
      }
  
      max_cost = new_max_cost;
  
      {
          FC_DEBUG("  CLEAN engine data:");
  
          // clean out all unused engine data
          EngineDataCache::Iterator it = engineDataCache.begin(),
                                   end = engineDataCache.end();
          while (it != end) {
              if (it.value()->ref != 0) {
                  ++it;
                  continue;
              }
  
              EngineDataCache::Iterator rem = it++;
  
              decreaseCost(sizeof(QFontEngineData));
  
              FC_DEBUG("    %p", rem.value());
  
              delete rem.value();
              engineDataCache.erase(rem);
          }
      }
  
      // clean out the engine cache just enough to get below our new max cost
      uint current_cost;
      do {
          current_cost = total_cost;
  
          EngineCache::Iterator it = engineCache.begin(),
                               end = engineCache.end();
          // determine the oldest and least popular of the unused engines
          uint oldest = ~0u;
          uint least_popular = ~0u;
  
          for (; it != end; ++it) {
              if (it.value().data->ref != 0)
                  continue;
  
              if (it.value().timestamp < oldest &&
                   it.value().hits <= least_popular) {
                  oldest = it.value().timestamp;
                  least_popular = it.value().hits;
              }
          }
  
          FC_DEBUG("    oldest %u least popular %u", oldest, least_popular);
  
          for (it = engineCache.begin(); it != end; ++it) {
              if (it.value().data->ref == 0 &&
                   it.value().timestamp == oldest &&
                   it.value().hits == least_popular)
                  break;
          }
  
          if (it != end) {
              FC_DEBUG("    %p: timestamp %4u hits %2u ref %2d/%2d, type '%s'",
                       it.value().data, it.value().timestamp, it.value().hits,
                       int(it.value().data->ref), it.value().data->cache_count,
                       it.value().data->name());
  
              if (--it.value().data->cache_count == 0) {
                  FC_DEBUG("    DELETE: last occurrence in cache");
  
                  decreaseCost(it.value().data->cache_cost);
                  delete it.value().data;
              } else {
                  /*
                    this particular font engine is in the cache multiple
                    times...  set current_cost to zero, so that we can
                    keep looping to get rid of all occurrences
                  */
                  current_cost = 0;
              }
  
              engineCache.erase(it);
          }
      } while (current_cost != total_cost && total_cost > max_cost);
  }
  
  
  #ifndef QT_NO_DEBUG_STREAM
  QDebug operator<<(QDebug stream, const QFont &font)
  {
      return stream << "QFont(" << font.toString() << ')';
  }
  #endif
  
  QT_END_NAMESPACE
  