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# qfontmanager_qws.h

This is the verbatim text of the qfontmanager_qws.h include file. It is provided only for illustration; the copyright remains with Trolltech.

    /****************************************************************************
    ** $Id: qt/qfontmanager_qws.h   3.3.8   edited Jan 11 14:38 $
    **
    ** Definition of font rendering infrastructure for Embedded Qt
    **
    ** Created : 940721
    **
    ** Copyright (C) 1992-2007 Trolltech ASA.  All rights reserved.
    **
    ** This file is part of the kernel module of the Qt GUI Toolkit.
    **
    ** This file may be distributed and/or modified under the terms of the
    ** GNU General Public License version 2 as published by the Free Software
    ** Foundation and appearing in the file LICENSE.GPL included in the
    ** packaging of this file.
    **
    ** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
    ** licenses for Qt/Embedded may use this file in accordance with the
    ** Qt Embedded Commercial License Agreement provided with the Software.
    **
    ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
    ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
    **
    ** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
    **   information about Qt Commercial License Agreements.
    ** See http://www.trolltech.com/gpl/ for GPL licensing information.
    **
    ** Contact info@trolltech.com if any conditions of this licensing are
    ** not clear to you.
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    **********************************************************************/

    #ifndef QFONTMANAGER_QWS_H
    #define QFONTMANAGER_QWS_H

    #ifndef QT_H
    #include "qfont.h"
    #include "qptrlist.h"
    #include <private/qtextengine_p.h>
    #endif // QT_H

    // These are stored in the shared memory segment in front of their
    // data, and indexed at the start of the segment

    // This needs to be a multiple of 64 bits

    class QFontDef;

    class Q_PACKED QGlyphMetrics {

    public:
        Q_UINT8 linestep;
        Q_UINT8 width;
        Q_UINT8 height;
        Q_UINT8 flags;

        Q_INT8 bearingx;      // Difference from pen position to glyph's left bbox
        Q_UINT8 advance;       // Difference between pen positions
        Q_INT8 bearingy;      // Used for putting characters on baseline

        Q_INT8 reserved;      // Do not use

        // Flags:
        // RendererOwnsData - the renderer is responsible for glyph data
        //                    memory deletion otherwise QGlyphTree must
        //                    delete [] the data when the glyph is deleted.
        enum Flags { RendererOwnsData=0x01 };
    };

    class QGlyph {
    public:
        QGlyph() { metrics=0; data=0; }
        QGlyph(QGlyphMetrics* m, uchar* d) :
    	metrics(m), data(d) { }
        ~QGlyph() {}

        QGlyphMetrics* metrics;
        uchar* data;
    };

    class QFontFactory;
    class QDiskFont;

    // This is a particular font instance at a particular resolution
    // e.g. Truetype Times, 10 point. There's only one of these though;
    // we want to share generated glyphs

    class QRenderedFont {

    public:

        // Normal font-type is monochrome; glyph data is a
        //   bitmap, which doesn't use much memory

        // Initialise for name A, renderer B, font type C, D glyphs

        QRenderedFont(QDiskFont *,const QFontDef&);
        virtual ~QRenderedFont();

        QFontDef fontDef() const;

        int refcount;

        int ptsize;

        bool italic;
        unsigned int weight;

        void ref() { refcount++; }
        bool deref() { refcount--; return refcount==0; }

        bool match(const QFontDef &);

        QDiskFont* diskfont;
        int fascent,fdescent;
        int fleftbearing,frightbearing;
        int fmaxwidth;
        int fleading;
        int funderlinepos;
        int funderlinewidth;
        bool smooth;
        int maxchar;

        int ascent() { return fascent; }
        int descent() { return fdescent; }
        int width(int);
        int width( const QString&, int =-1 );
        int leftBearing(int);
        int rightBearing(int);

        // Calling any of these can trigger a full-font metrics check
        // which can be expensive
        int minLeftBearing();
        int minRightBearing();
        int maxWidth();

        virtual bool inFont(glyph_t g) const=0;
        virtual QGlyph render(glyph_t g)=0;

    private:

    };

    // Keeps track of available renderers and which font is which

    class QDiskFontPrivate {};

    class QDiskFont {

    public:
        QDiskFont(QFontFactory *f, const QString& n, bool i, int w, int s,
    	      const QString &fl, const QString& fi) :
    	factory(f), name(n), italic(i), weight(w), size(s), flags(fl), file(fi)
        {
    	loaded=FALSE;
    	p=0;
        }

        QRenderedFont* load(const QFontDef &);

        QFontDef fontDef() const;

        QFontFactory *factory;
        QString name;
        bool italic;
        int weight;
        int size;
        QString flags;
        QString file;
        bool loaded;

        QDiskFontPrivate * p;
    };

    class QCachePolicy {

    public:

        virtual void cache(QRenderedFont *)=0;
        virtual void uncache(QRenderedFont *)=0;

    };

    // Exposed here so the default policy can be reset

    class QDefaultCachePolicy : public QCachePolicy {

    public:

        virtual void cache(QRenderedFont *);
        virtual void uncache(QRenderedFont *);

    };

    class QFontManager {

    public:

        QPtrList<QFontFactory> factories;
        QPtrList<QRenderedFont> cachedfonts;
        QPtrList<QDiskFont> diskfonts;

        QFontManager();
        ~QFontManager();

        // Font definition, type and color
        QDiskFont * get(const QFontDef &);

        static int cmpFontDef(const QFontDef & goal, const QFontDef & choice);

        static void initialize();
        static void cleanup();

        void setPolicy(QCachePolicy *);

        void cache(QRenderedFont * f) { policy->cache(f); }
        void uncache(QRenderedFont * f) { policy->uncache(f); }
        QRenderedFont * getCached(const QFontDef &);

    private:

        QCachePolicy * policy;

    };

    class QFontFactory {

    public:

        QFontFactory() {}
        virtual ~QFontFactory() {}

        virtual QRenderedFont * get(const QFontDef &,QDiskFont *)=0;
        virtual void load(QDiskFont *) const=0;
        virtual void unload(QDiskFont *) {}
        virtual QString name()=0;
    };

    void qt_init_fonts();

    extern QFontManager * qt_fontmanager;

    #endif