inline void QwtPolygonClipperF::addPoint(QwtPolygonF &pa, uint pos, const QwtDoublePoint &point) const
{
    if ( uint(pa.size()) <= pos ) 
        pa.resize(pos + 5);

    pa[(int)pos] = point;
}
Esempio n. 2
0
void QwtPainter::drawPolyline(QPainter *painter, const QwtPolygonF &pa)
{
    QRect clipRect;
    const bool deviceClipping = isClippingNeeded(painter, clipRect);

    QwtPolygonF cpa = d_metricsMap.layoutToDevice(pa);
    if ( deviceClipping )
        cpa = QwtClipper::clipPolygonF(clipRect, cpa);

#if QT_VERSION >= 0x040000
    bool doSplit = false;

    const QPaintEngine *pe = painter->paintEngine();
    if ( pe && pe->type() == QPaintEngine::Raster &&
        painter->pen().width() >= 2 )
    {
        /*
            The raster paint engine seems to use some algo with O(n*n).
            ( Qt 4.3 is better than Qt 4.2, but remains unacceptable)
            To work around this problem, we have to split the polygon into
            smaller pieces.
         */
        doSplit = true;
    }

    if ( doSplit )
    {
        const int numPoints = cpa.size();
        const QPointF *points = cpa.data();

        const int splitSize = 20;
        for ( int i = 0; i < numPoints; i += splitSize )
        {
            const int n = qwtMin(splitSize + 1, cpa.size() - i);
            painter->drawPolyline(points + i, n);
        }
    }
    else
#endif
        painter->drawPolyline(cpa);
}
/*!
  \brief Complete a polygon to be a closed polygon
         including the area between the original polygon
         and the baseline.
  \param xMap X map
  \param yMap Y map
  \param pa Polygon to be completed
*/
void QwtPlotCurve::closePolyline(
    const QwtScaleMap &xMap, const QwtScaleMap &yMap,
    QwtPolygonF &pa) const
{
    const int sz = pa.size();
    if ( sz < 2 )
        return;

    pa.resize(sz + 2);

    if ( d_data->curveType == QwtPlotCurve::Xfy )
    {
        pa[sz] = QPointF(xMap.transform(d_data->reference), pa[sz - 1].y());
        pa[sz + 1] = QPointF(xMap.transform(d_data->reference), pa[0].y());
    }
    else
    {
        pa[sz] = QPointF(pa[sz - 1].x(), yMap.transform(d_data->reference));
        pa[pa.size() - 1] = QPointF(pa[0].x(), yMap.transform(d_data->reference));
    }
}
//! Sutherland-Hodgman polygon clipping
QwtPolygonF QwtPolygonClipperF::clipPolygon(const QwtPolygonF &pa) const
{
    if ( contains( ::boundingRect(pa) ) )
        return pa;

    QwtPolygonF cpa(pa.size());

    clipEdge((Edge)0, pa, cpa);

    for ( uint edge = 1; edge < NEdges; edge++ ) 
    {
        const QwtPolygonF rpa = cpa;
#if QT_VERSION < 0x040000
        cpa.detach();
#endif
        clipEdge((Edge)edge, rpa, cpa);
    }

    return cpa;
}
void QwtPolygonClipperF::clipEdge(Edge edge, 
    const QwtPolygonF &pa, QwtPolygonF &cpa) const
{
    if ( pa.count() == 0 )
    {
        cpa.resize(0);
        return;
    }

    unsigned int count = 0;

    QwtDoublePoint p1 = pa[0];
    if ( insideEdge(p1, edge) )
        addPoint(cpa, count++, p1);

    const uint nPoints = pa.size();
    for ( uint i = 1; i < nPoints; i++ )
    {
        const QwtDoublePoint p2 = pa[(int)i];
        if ( insideEdge(p2, edge) )
        {
            if ( insideEdge(p1, edge) )
                addPoint(cpa, count++, p2);
            else
            {
                addPoint(cpa, count++, intersectEdge(p1, p2, edge));
                addPoint(cpa, count++, p2);
            }
        }
        else
        {
            if ( insideEdge(p1, edge) )
                addPoint(cpa, count++, intersectEdge(p1, p2, edge));
        }
        p1 = p2;
    }
    cpa.resize(count);
}
/*!
  Draw dots

  \param painter Painter
  \param xMap x map
  \param yMap y map
  \param from index of the first point to be painted
  \param to index of the last point to be painted

  \sa draw(), drawCurve(), drawSticks(), drawLines(), drawSteps()
*/
void QwtPlotCurve::drawDots(QPainter *painter,
    const QwtScaleMap &xMap, const QwtScaleMap &yMap,
    int from, int to) const
{
    const QRect window = painter->window();
    if ( window.isEmpty() )
        return;

    const bool doFill = d_data->brush.style() != Qt::NoBrush;

    QwtPolygonF polyline;
    if ( doFill )
        polyline.resize(to - from + 1);

    if ( to > from && d_data->paintAttributes & PaintFiltered )
    {
        if ( doFill )
        {
            QPointF pp( xMap.xTransform(x(from)), yMap.xTransform(y(from)) );

            QwtPainter::drawPoint(painter, pp.x(), pp.y());
            polyline[0] = pp;

            int count = 1;
            for (int i = from + 1; i <= to; i++)
            {
                const QPointF pi(xMap.xTransform(x(i)), yMap.xTransform(y(i)));
                if ( pi != pp )
                {
                    QwtPainter::drawPoint(painter, pi.x(), pi.y());

                    polyline[count] = pi;
                    count++;

                    pp = pi;
                }
            }
            if ( int(polyline.size()) != count )
                polyline.resize(count);
        }
        else
        {
            // if we don't need to fill, we can sort out
            // duplicates independent from the order

            PrivateData::PixelMatrix pixelMatrix(window);

            for (int i = from; i <= to; i++)
            {
                const QPointF p( xMap.xTransform(x(i)), yMap.xTransform(y(i)) );

                if ( pixelMatrix.testPixel(p.toPoint()) )
                    QwtPainter::drawPoint(painter, p.x(), p.y());
            }
        }
    }
    else
    {
        for (int i = from; i <= to; i++)
        {
            const double xi = xMap.xTransform(x(i));
            const double yi = yMap.xTransform(y(i));
            QwtPainter::drawPoint(painter, xi, yi);

            if ( doFill )
                polyline[i - from] = QPointF(xi, yi);
        }
    }

    if ( doFill )
    {
        if ( d_data->paintAttributes & ClipPolygons )
            polyline = QwtClipper::clipPolygonF(painter->window(), polyline);

        fillCurve(painter, xMap, yMap, polyline);
    }
}
Esempio n. 7
-1
static inline QwtDoubleRect boundingRect(const QwtPolygonF &polygon)
{
#if QT_VERSION < 0x040000
    if (polygon.isEmpty())
        return QwtDoubleRect(0, 0, 0, 0);

    register const QwtDoublePoint *pd = polygon.data();

    double minx, maxx, miny, maxy;
    minx = maxx = pd->x();
    miny = maxy = pd->y();
    pd++;

    for (uint i = 1; i < polygon.size(); i++, pd++) 
    {
        if (pd->x() < minx)
            minx = pd->x();
        else if (pd->x() > maxx)
            maxx = pd->x();
        if (pd->y() < miny)
            miny = pd->y();
        else if (pd->y() > maxy)
            maxy = pd->y();
    }
    return QwtDoubleRect(minx, miny, maxx - minx, maxy - miny);
#else
    return polygon.boundingRect();
#endif
}