qfontengine_x11.cpp

奇趣公司比较新的qt/emd版本

            && s[i].unicode() >= 0xd800 && s[i].unicode() < 0xdc00
            && s[i+1].unicode() >= 0xdc00 && s[i].unicode() < 0xe000) {
            *str = QChar();
            ++i;
        } else {
            *str = s[i];
        }
        ++str;
    }

    len = str - (QChar *)_s.data();
    str = (QChar *)_s.data();

    bool mirrored = flags & QTextEngine::RightToLeft;
    if (_codec) {
        bool haveNbsp = false;
        for (int i = 0; i < len; i++)
            if (str[i].unicode() == 0xa0) {
                haveNbsp = true;
                break;
            }

        QVarLengthArray<unsigned short> ch(len);
        QChar *chars = (QChar *)ch.data();
        if (haveNbsp || mirrored) {
            for (int i = 0; i < len; i++)
                chars[i] = (str[i].unicode() == 0xa0 ? 0x20 :
                            (mirrored ? QChar::mirroredChar(str[i].unicode()) : str[i].unicode()));
        } else {
            for (int i = 0; i < len; i++)
                chars[i] = str[i].unicode();
        }
        QTextCodec::ConverterState state;
        state.flags = QTextCodec::ConvertInvalidToNull;
        QByteArray ba = _codec->fromUnicode(chars, len, &state);
        if (ba.length() == 2*len) {
            // double byte encoding
            const uchar *data = (const uchar *)ba.constData();
            for (int i = 0; i < len; i++) {
                glyphs[i].glyph = ((ushort)data[0] << 8) + data[1];
                data += 2;
            }
        } else {
            const uchar *data = (const uchar *)ba.constData();
            for (int i = 0; i < len; i++)
                glyphs[i].glyph = (ushort)data[i];
        }
    } else {
        QGlyphLayout *g = glyphs + len;
        const QChar *c = str + len;
        if (mirrored) {
            while (c != str)
                (--g)->glyph = (--c)->unicode() == 0xa0 ? 0x20 : QChar::mirroredChar(c->unicode());
        } else {
            while (c != str)
                (--g)->glyph = (--c)->unicode() == 0xa0 ? 0x20 : c->unicode();
        }
    }
    *nglyphs = len;

    QGlyphLayout *g = glyphs + len;
    XCharStruct *xcs;
    // inlined for better perfomance
    if (!_fs->per_char) {
        xcs = &_fs->min_bounds;
        while (g != glyphs) {
            --g;
            const unsigned char r = g->glyph >> 8;
            const unsigned char c = g->glyph & 0xff;
            if (r >= _fs->min_byte1 &&
                r <= _fs->max_byte1 &&
                c >= _fs->min_char_or_byte2 &&
                c <= _fs->max_char_or_byte2) {
                g->advance.x = xcs->width;
            } else {
                g->glyph = 0;
            }
        }
    }
    else if (!_fs->max_byte1) {
        XCharStruct *base = _fs->per_char - _fs->min_char_or_byte2;
        while (g != glyphs) {
            unsigned int gl = (--g)->glyph;
            xcs = (gl >= _fs->min_char_or_byte2 && gl <= _fs->max_char_or_byte2) ?
                  base + gl : 0;
            if (!xcs || (!xcs->width && !xcs->ascent && !xcs->descent)) {
                g->glyph = 0;
            } else {
                g->advance.x = xcs->width;
            }
        }
    }
    else {
        while (g != glyphs) {
            xcs = charStruct(_fs, (--g)->glyph);
            if (!xcs) {
                g->glyph = 0;
            } else {
                g->advance.x = xcs->width;
            }
        }
    }
    return true;
}

glyph_metrics_t QFontEngineXLFD::boundingBox(const QGlyphLayout *glyphs, int numGlyphs)
{
    int i;

    glyph_metrics_t overall;
    // initialize with line height, we get the same behaviour on all platforms
    overall.y = -ascent();
    overall.height = ascent() + descent() + 1;
    QFixed ymax;
    QFixed xmax;
    for (i = 0; i < numGlyphs; i++) {
        XCharStruct *xcs = charStruct(_fs, glyphs[i].glyph);
        if (xcs) {
            QFixed x = overall.xoff + glyphs[i].offset.x + xcs->lbearing;
            QFixed y = overall.yoff + glyphs[i].offset.y - xcs->ascent;
            overall.x = qMin(overall.x, x);
            overall.y = qMin(overall.y, y);
            xmax = qMax(xmax, overall.xoff + glyphs[i].offset.x + xcs->rbearing);
            ymax = qMax(ymax, y + xcs->ascent + xcs->descent);
            overall.xoff += glyphs[i].advance.x;
        } else {
            QFixed size = _fs->ascent;
            overall.x = qMin(overall.x, overall.xoff);
            overall.y = qMin(overall.y, overall.yoff - size);
            ymax = qMax(ymax, overall.yoff);
            overall.xoff += size;
            xmax = qMax(xmax, overall.xoff);
        }
    }
    overall.height = qMax(overall.height, ymax - overall.y);
    overall.width = xmax - overall.x;

    return overall;
}

glyph_metrics_t QFontEngineXLFD::boundingBox(glyph_t glyph)
{
    glyph_metrics_t gm;
    XCharStruct *xcs = charStruct(_fs, glyph);
    if (xcs) {
        gm = glyph_metrics_t(xcs->lbearing, -xcs->ascent, xcs->rbearing- xcs->lbearing, xcs->ascent + xcs->descent,
                              xcs->width, 0);
    } else {
        QFixed size = ascent();
        gm = glyph_metrics_t(0, size, size, size, size, 0);
    }
    return gm;
}

QFixed QFontEngineXLFD::ascent() const
{
    return _fs->ascent;
}

QFixed QFontEngineXLFD::descent() const
{
    return (_fs->descent-1);
}

QFixed QFontEngineXLFD::leading() const
{
    QFixed l = QFixed(qMin<int>(_fs->ascent, _fs->max_bounds.ascent)
                      + qMin<int>(_fs->descent, _fs->max_bounds.descent)) * QFixed::fromReal(0.15);
    return l.ceil();
}

qreal QFontEngineXLFD::maxCharWidth() const
{
    return _fs->max_bounds.width;
}


// Loads the font for the specified script
static inline int maxIndex(XFontStruct *f) {
    return (((f->max_byte1 - f->min_byte1) *
             (f->max_char_or_byte2 - f->min_char_or_byte2 + 1)) +
            f->max_char_or_byte2 - f->min_char_or_byte2);
}

qreal QFontEngineXLFD::minLeftBearing() const
{
    if (lbearing == SHRT_MIN) {
        if (_fs->per_char) {
            XCharStruct *cs = _fs->per_char;
            int nc = maxIndex(_fs) + 1;
            int mx = cs->lbearing;

            for (int c = 1; c < nc; c++) {
                // ignore the bearings for characters whose ink is
                // completely outside the normal bounding box
                if ((cs[c].lbearing <= 0 && cs[c].rbearing <= 0) ||
                    (cs[c].lbearing >= cs[c].width && cs[c].rbearing >= cs[c].width))
                    continue;

                int nmx = cs[c].lbearing;

                if (nmx < mx)
                    mx = nmx;
            }

            ((QFontEngineXLFD *)this)->lbearing = mx;
        } else
            ((QFontEngineXLFD *)this)->lbearing = _fs->min_bounds.lbearing;
    }
    return lbearing;
}

qreal QFontEngineXLFD::minRightBearing() const
{
    if (rbearing == SHRT_MIN) {
        if (_fs->per_char) {
            XCharStruct *cs = _fs->per_char;
            int nc = maxIndex(_fs) + 1;
            int mx = cs->rbearing;

            for (int c = 1; c < nc; c++) {
                // ignore the bearings for characters whose ink is
                // completely outside the normal bounding box
                if ((cs[c].lbearing <= 0 && cs[c].rbearing <= 0) ||
                    (cs[c].lbearing >= cs[c].width && cs[c].rbearing >= cs[c].width))
                    continue;

                int nmx = cs[c].rbearing;

                if (nmx < mx)
                    mx = nmx;
            }

            ((QFontEngineXLFD *)this)->rbearing = mx;
        } else
            ((QFontEngineXLFD *)this)->rbearing = _fs->min_bounds.rbearing;
    }
    return rbearing;
}

const char *QFontEngineXLFD::name() const
{
    return _name;
}

bool QFontEngineXLFD::canRender(const QChar *string, int len)
{
    QVarLengthArray<QGlyphLayout, 256> glyphs(len);
    int nglyphs = len;
    if (stringToCMap(string, len, glyphs.data(), &nglyphs, 0) == false) {
        glyphs.resize(nglyphs);
        stringToCMap(string, len, glyphs.data(), &nglyphs, 0);
    }

    bool allExist = true;
    for (int i = 0; i < nglyphs; i++) {
        if (!glyphs[i].glyph || !charStruct(_fs, glyphs[i].glyph)) {
            allExist = false;
            break;
        }
    }

    return allExist;
}

void QFontEngineXLFD::addOutlineToPath(qreal x, qreal y, const QGlyphLayout *glyphs, int numGlyphs, QPainterPath *path, QTextItem::RenderFlags flags)
{
    addBitmapFontToPath(x, y, glyphs, numGlyphs, path, flags);
}

QFontEngine::FaceId QFontEngineXLFD::faceId() const
{
#ifndef QT_NO_FREETYPE
    if (face_id.index == -1) {
        face_id = ::fontFile(_name, &freetype, &synth);
        if (_codec)
            face_id.encoding = _codec->mibEnum();
        if (freetype) {
            const_cast<QFontEngineXLFD *>(this)->fsType = freetype->fsType();
        } else {
            QFontEngine::Properties properties = QFontEngine::properties();
            face_id.index = 0;
            face_id.filename = "-" + properties.postscriptName;
        }
    }
#endif

    return face_id;
}

QFontEngine::Properties QFontEngineXLFD::properties() const
{
    if (face_id.index == -1)
        (void)faceId();

#ifndef QT_NO_FREETYPE
    if (freetype)
        return freetype->properties();
#endif
    return QFontEngine::properties();
}

void QFontEngineXLFD::getUnscaledGlyph(glyph_t glyph, QPainterPath *path, glyph_metrics_t *metrics)
{
    if (face_id.index == -1)
        (void)faceId();
#ifndef QT_NO_FREETYPE
    if (!freetype)
#endif
    {
        QFontEngine::getUnscaledGlyph(glyph, path, metrics);
        return;
    }

#ifndef QT_NO_FREETYPE
    freetype->lock();

    FT_Face face = freetype->face;
    FT_Set_Char_Size(face, face->units_per_EM << 6, face->units_per_EM << 6, 0, 0);
    freetype->xsize = face->units_per_EM << 6;
    freetype->ysize = face->units_per_EM << 6;
    FT_Set_Transform(face, 0, 0);
    glyph = glyphIndexToFreetypeGlyphIndex(glyph);
    FT_Load_Glyph(face, glyph, FT_LOAD_NO_BITMAP);

    int left  = face->glyph->metrics.horiBearingX;