Parts of plot dissapear during scrolling

[myzinsky]

Hi,

i created a horizontal "timing" diagram and i use a self definded symbol!

when i scroll now a little to the right the two big bars dissapear!

(look at the picutres)

how can i fix that?

timing.jpg
timing2.jpg

regards
Matthias

[Uwe]

i created a horizontal "timing" diagram and i use a self definded symbol!

Guess you are using a QwtPlotIntervalCurve and you have overloaded QwtIntervalSymbol::draw() ?

If so show your code - if not throw all your code away beside that couple of lines you need to implement YourIntervalSymbol::draw().

Uwe

[myzinsky]

Guess you are using a QwtPlotIntervalCurve and you have overloaded QwtIntervalSymbol::draw() ?

Yes im using QwtPlotIntervalCurve and i overload draw:

class timingSignal: public QwtIntervalSymbol
    {
        public:
        virtual void draw( QPainter * painter, Qt::Orientation o, const QPointF& from, const QPointF& to ) const
        {
 
            //     2----------3
            //  1 /            \ 4
            //    \            /
            //    6------------5
 
            QPolygonF polygon;
            polygon << from                                 // 1
                    << QPointF(from.x()+10 , from.y()-10)   // 2
                    << QPointF(to.x()  -10 , to.y()  -10)   // 3
                    << to                                   // 4
                    << QPointF(to.x()  -10 , to.y()  +10)   // 6
                    << QPointF(from.x()+10 , from.y()+10);  // 7
 
            ///QwtPainter::drawText(painter, from, "blubb");
 
            QPen pen;
            pen.setWidth(2);
            //    pen.setStyle(Qt::SolidLine);
            //    pen.setBrush(Qt::red);
                pen.setCapStyle(Qt::SquareCap);
                pen.setJoinStyle(Qt::RoundJoin);
            painter->setBrush(QBrush(QColor(120,120,120,200),Qt::SolidPattern));
            painter->setPen(pen);
            QwtPainter::drawPolygon( painter, polygon);
 
        }
 
    };

class timingSignal: public QwtIntervalSymbol
    {
        public:
        virtual void draw( QPainter * painter, Qt::Orientation o, const QPointF& from, const QPointF& to ) const
        {

            //     2----------3
            //  1 /            \ 4
            //    \            /
            //    6------------5

            QPolygonF polygon;
            polygon << from                                 // 1
                    << QPointF(from.x()+10 , from.y()-10)   // 2
                    << QPointF(to.x()  -10 , to.y()  -10)   // 3
                    << to                                   // 4
                    << QPointF(to.x()  -10 , to.y()  +10)   // 6
                    << QPointF(from.x()+10 , from.y()+10);  // 7

            ///QwtPainter::drawText(painter, from, "blubb");

            QPen pen;
            pen.setWidth(2);
            //    pen.setStyle(Qt::SolidLine);
            //    pen.setBrush(Qt::red);
                pen.setCapStyle(Qt::SquareCap);
                pen.setJoinStyle(Qt::RoundJoin);
            painter->setBrush(QBrush(QColor(120,120,120,200),Qt::SolidPattern));
            painter->setPen(pen);
            QwtPainter::drawPolygon( painter, polygon);

        }

    };

To copy to clipboard, switch view to plain text mode 

[myzinsky]

I changed it to a normal rectangle, and its the same behavior...

[Uwe]

I changed it to a normal rectangle, and its the same behavior...

1. Is the draw methods called for the missing symbol and with what coordinates ?
2. What happens, when you disable the ClipSymbol paint attribute of the curve ?

Uwe

---

Added after 7 minutes:

O.k. after looking into the code I see a bug related to the ClipSymbol paint attribute for horizontal symbols. In qwtIsHSampleInside() a x coordinate gets compared against yMax ( instead of xMax ).

Disable the ClipSymbol paint attribute - or use the fix from SVN ( trunk or 6,0 branch ).

Uwe

[myzinsky]

curve->setPaintAttribute(QwtPlotIntervalCurve::ClipPolygons,false);

curve->setPaintAttribute(QwtPlotIntervalCurve::ClipPolygons,false);

To copy to clipboard, switch view to plain text mode 

did the job!
thanks uwe!