q3paintengine_svg.cpp

奇趣公司比较新的qt/emd版本

        index += reg.matchedLength();
    }
}
/*!
    \internal

    Push the current drawing attributes on a stack.

    \sa restoreAttributes()
*/

void Q3SVGPaintEnginePrivate::saveAttributes(QPainter *pt)
{
    pt->save();
    // copy old state
    Q3SVGPaintEngineState st(*curr);
    stack.append(st);
    curr = &stack.last();
}

/*!
    \internal

    Pop the current drawing attributes off the stack.

    \sa saveAttributes()
*/

void Q3SVGPaintEnginePrivate::restoreAttributes(QPainter *pt)
{
    pt->restore();
    Q_ASSERT(stack.count() > 1);
    stack.removeLast();
    curr = &stack.last();
}

void Q3SVGPaintEnginePrivate::setStyle(const QString &s, QPainter *pt)
{
    QStringList rules = s.split(QLatin1Char(';'), QString::SkipEmptyParts);

    QPen pen = pt->pen();
    QFont font = pt->font();

    QStringList::ConstIterator it = rules.constBegin();
    for (; it != rules.constEnd(); it++) {
        int col = (*it).indexOf(QLatin1Char(':'));
        if (col > 0) {
            QString prop = (*it).left(col).simplified();
            QString val = (*it).right((*it).length() - col - 1);
            val = val.toLower().trimmed();
            setStyleProperty(prop, val, &pen, &font, &curr->textalign, pt);
        }
    }
    pt->setPen(pen);
    pt->setFont(font);
}

void Q3SVGPaintEnginePrivate::setStyleProperty(const QString &prop, const QString &val, QPen *pen,
                                       QFont *font, int *talign, QPainter *pt)
{
    if (prop == QLatin1String("stroke")) {
        if (val == QLatin1String("none")) {
            pen->setStyle(Qt::NoPen);
        } else {
            pen->setColor(parseColor(val));
            if (pen->style() == Qt::NoPen)
                pen->setStyle(Qt::SolidLine);
            if (pen->width() == 0)
                pen->setWidth(1);
        }
    } else if (prop == QLatin1String("stroke-opacity")) {
        double opacity = parseLen(val);
        QColor c = pen->color();
        c.setAlpha((int)(opacity*255));
        pen->setColor(c);
    } else if (prop == QLatin1String("fill-opacity")) {
        double opacity = parseLen(val);
        QColor c = pt->brush().color();
        c.setAlpha((int)(opacity*255));
        pt->setBrush(c);
    } else if (prop == QLatin1String("stroke-width")) {
        double w = parseLen(val);
        if (w > 0.0001)
            pen->setWidth(int(w));
        else
            pen->setStyle(Qt::NoPen);
    } else if (prop == QLatin1String("stroke-linecap")) {
        if (val == QLatin1String("butt"))
            pen->setCapStyle(Qt::FlatCap);
        else if (val == QLatin1String("round"))
            pen->setCapStyle(Qt::RoundCap);
        else if (val == QLatin1String("square"))
            pen->setCapStyle(Qt::SquareCap);
    } else if (prop == QLatin1String("stroke-linejoin")) {
        if (val == QLatin1String("miter"))
            pen->setJoinStyle(Qt::MiterJoin);
        else if (val == QLatin1String("round"))
            pen->setJoinStyle(Qt::RoundJoin);
        else if (val == QLatin1String("bevel"))
            pen->setJoinStyle(Qt::BevelJoin);
    } else if (prop == QLatin1String("stroke-dasharray")) {
        if (val == QLatin1String("18,6"))
            pen->setStyle(Qt::DashLine);
        else if (val == QLatin1String("3"))
            pen->setStyle(Qt::DotLine);
        else if (val == QLatin1String("9,6,3,6"))
            pen->setStyle(Qt::DashDotLine);
        else if (val == QLatin1String("9,3,3"))
            pen->setStyle(Qt::DashDotDotLine);
    } else if (prop == QLatin1String("fill")) {
        if (val == QLatin1String("none"))
            pt->setBrush(Qt::NoBrush);
        else
            pt->setBrush(parseColor(val));
    } else if (prop == QLatin1String("font-size")) {
        font->setPixelSize(qRound(parseLen(val)));
    } else if (prop == QLatin1String("font-family")) {
        font->setFamily(val);
    } else if (prop == QLatin1String("font-style")) {
        if (val == QLatin1String("normal"))
            font->setItalic(false);
        else if (val == QLatin1String("italic"))
            font->setItalic(true);
        else
            qWarning("QSvgDevice::setStyleProperty: unhandled font-style: %s", val.latin1());
    } else if (prop == QLatin1String("font-weight")) {
        int w = font->weight();
        // no exact equivalents so we have to QLatin1String("round") a little bit
        if (val == QLatin1String("100") || val == QLatin1String("200"))
            w = QFont::Light;
        if (val == QLatin1String("300") || val == QLatin1String("400") || val == QLatin1String("normal"))
            w = QFont::Normal;
        else if (val == QLatin1String("500") || val == QLatin1String("600"))
            w = QFont::DemiBold;
        else if (val == QLatin1String("700") || val == QLatin1String("bold") || val == QLatin1String("800"))
            w = QFont::Bold;
        else if (val == QLatin1String("900"))
            w = QFont::Black;
        font->setWeight(w);
    } else if (prop == QLatin1String("text-anchor")) {
        if (val == QLatin1String("middle"))
            *talign = Qt::AlignHCenter;
        else if (val == QLatin1String("end"))
            *talign = Qt::AlignRight;
        else
            *talign = Qt::AlignLeft;
    }
}

void Q3SVGPaintEnginePrivate::drawPath(const QString &data, QPainter *pt)
{
    double x0 = 0, y0 = 0;              // starting point
    double x = 0, y = 0;                // current point
    QPointF ctrlPt;
    QPainterPath path;                  // resulting path
    int idx = 0;                        // current data position
    int mode = 0, lastMode = 0;         // parser state
    bool relative = false;              // e.g. 'h' vs. 'H'
    QString commands(QLatin1String("MZLHVCSQTA"));     // recognized commands
    int cmdArgs[] = { 2, 0, 2, 1, 1, 6, 4, 4, 2, 7 };                   // no of arguments
    QRegExp reg(QString::fromLatin1("\\s*,?\\s*([+-]?\\d*\\.?\\d*)"));  // floating point

    // detect next command
    while (idx < data.length()) {
        QChar ch = data[(int)idx++];
        if (ch.isSpace())
            continue;
        QChar chUp = ch.toUpper();
        int cmd = commands.indexOf(chUp);
        if (cmd >= 0) {
            // switch to new command mode
            mode = cmd;
            relative = (ch != chUp);                // e.g. 'm' instead of 'M'
        } else {
            if (mode && !ch.isLetter()) {
                cmd = mode;                        // continue in previous mode
                idx--;
            } else {
                qWarning("Q3SVGPaintEngine::drawPath: Unknown command");
                return;
            }
        }

        // read in the required number of arguments
        const int maxArgs = 7;
        double arg[maxArgs];
        int numArgs = cmdArgs[cmd];
        for (int i = 0; i < numArgs; i++) {
            int pos = reg.indexIn(data, idx);
            if (pos == -1) {
                qWarning("Q3SVGPaintEngine::drawPath: Error parsing arguments");
                return;
            }
            arg[i] = reg.cap(1).toDouble();
            idx = pos + reg.matchedLength();
        };

        // process command
        double offsetX = relative ? x : 0;        // correction offsets
        double offsetY = relative ? y : 0;        // for relative commands
        switch (mode) {
        case 0:                                        // 'M' move to
            x = x0 = arg[0] + offsetX;
            y = y0 = arg[1] + offsetY;
            path.moveTo(x0, y0);
            mode = 2;                                  // -> 'L'
            break;
        case 1:                                        // 'Z' close path
            x = x0;
            y = y0;
            path.closeSubpath();
            mode = 0;
            break;
        case 2:                                        // 'L' line to
            x = arg[0] + offsetX;
            y = arg[1] + offsetY;
            path.lineTo(x, y);
            break;
        case 3:                                        // 'H' horizontal line
            x = arg[0] + offsetX;
            path.lineTo(x, y);
            break;
        case 4:                                        // 'V' vertical line
            y = arg[0] + offsetY;
            path.lineTo(x, y);
            break;
        case 5: {                                        // 'C' cubic bezier curveto
            QPointF c1(arg[0]+offsetX, arg[1]+offsetY);
            QPointF c2(arg[2]+offsetX, arg[3]+offsetY);
            QPointF e(arg[4]+offsetX, arg[5]+offsetY);
            path.cubicTo(c1, c2, e);
            ctrlPt = c2;
            x = e.x();
            y = e.y();
            break;
        }
        case 6: {                                        // 'S' smooth shorthand
            QPointF c1;
            if (lastMode == 5 || lastMode == 6)
                c1 = QPointF(2*x-ctrlPt.x(), 2*y-ctrlPt.y());
            else
                c1 = QPointF(x, y);
            QPointF c2(arg[0]+offsetX, arg[1]+offsetY);
            QPointF e(arg[2]+offsetX, arg[3]+offsetY);
            path.cubicTo(c1, c2, e);
            ctrlPt = c2;
            x = e.x();
            y = e.y();
            break;
        }
        case 7: {                                        // 'Q' quadratic bezier curves
            QPointF c(arg[0]+offsetX, arg[1]+offsetY);
            QPointF e(arg[2]+offsetX, arg[3]+offsetY);
            path.quadTo(c, e);
            ctrlPt = c;
            x = e.x();
            y = e.y();
            break;
        }
        case 8: {                                      // 'T' smooth shorthand
            QPointF e(arg[0]+offsetX, arg[1]+offsetY);
            QPointF c;
            if (lastMode == 7 || lastMode == 8)
                c = QPointF(2*x-ctrlPt.x(), 2*y-ctrlPt.y());
            else
                c = QPointF(x, y);
            path.quadTo(c, e);
            ctrlPt = c;
            x = e.x();
            y = e.y();
            break;
        }
        case 9:                                        // 'A' elliptical arc curve
            // ### just a straight line
            x = arg[5] + offsetX;
            y = arg[6] + offsetY;
            path.lineTo(x, y);
            break;
        };
        lastMode = mode;
    }
    pt->drawPath(path);
}

/*!
    \internal

    Parses a CSS2-compatible color specification. Either a keyword or
    a numerical RGB specification like #ff00ff or rgb(255,0,50%).
*/

QColor Q3SVGPaintEnginePrivate::parseColor(const QString &col)
{
    static const struct ColorTable {
        const char *name;
        const char *rgb;
    } coltab[] = {
        { "black",   "#000000" },
        { "silver",  "#c0c0c0" },
        { "gray",    "#808080" },
        { "white",   "#ffffff" },
        { "maroon",  "#800000" },
        { "red",     "#ff0000" },
        { "purple",  "#800080" },
        { "fuchsia", "#ff00ff" },
        { "green",   "#008000" },
        { "lime",    "#00ff00" },
        { "olive",   "#808000" },
        { "yellow",  "#ffff00" },
        { "navy",    "#000080" },
        { "blue",    "#0000ff" },
        { "teal",    "#008080" },
        { "aqua",    "#00ffff" },
        // ### the latest spec has more
        { 0,         0         }
    };

    // initialize color map on first use
    if (!qSvgColMap) {
        qSvgColMap = new QMap<QString,QString>;
        const struct ColorTable *t = coltab;
        while (t->name) {
            qSvgColMap->insert(QLatin1String(t->name), QLatin1String(t->rgb));
            ++t;
        }
    }

    // a keyword?
    if (qSvgColMap->contains(col))
        return QColor((*qSvgColMap)[col]);
    // in rgb(r,g,b) form ?
    QString c = col;
    c.replace(QRegExp(QString::fromLatin1("\\s*")), QLatin1String(""));
    QRegExp reg(QString::fromLatin1("^rgb\\((\\d+)(%?),(\\d+)(%?),(\\d+)(%?)\\)$"));
    if (reg.indexIn(c) >= 0) {
        int comp[3];
        for (int i = 0; i < 3; i++) {
            comp[i] = reg.cap(2*i+1).toInt();
            if (!reg.cap(2*i+2).isEmpty())                // percentage ?
                comp[i] = int((double(255*comp[i])/100.0));
        }
        return QColor(comp[0], comp[1], comp[2]);
    }

    // check for predefined Qt color objects, #RRGGBB and #RGB
    return QColor(col);
}

static QString qt_svg_compose_path(const QPainterPath &path)
{
    QString str, tmp;
    for (int i = 0; i < path.elementCount(); ++i) {
        const QPainterPath::Element &elm = path.elementAt(i);
        switch (elm.type) {
        case QPainterPath::LineToElement:
            tmp.sprintf("L %f %f ", elm.x, elm.y);
            str += tmp;
            break;
        case QPainterPath::MoveToElement:
            tmp.sprintf("M %f %f ", elm.x, elm.y);
            str += tmp;
            break;
        case QPainterPath::CurveToElement:
        {
            Q_ASSERT(path.elementCount() > i+2);
            const QPainterPath::Element cd1 = path.elementAt(i+1);
            const QPainterPath::Element cd2 = path.elementAt(i+2);
            Q_ASSERT(cd1.type == QPainterPath::CurveToDataElement
                     && cd2.type == QPainterPath::CurveToDataElement);
            tmp.sprintf("C %f %f %f %f %f %f ", elm.x, elm.y, cd1.x, cd1.y, cd2.x, cd2.y);
            str += tmp;
            i += 2;
            break;
        }
        default:
            break;
        }
    }
    return str;
}