QwtPlotCurve shift by 1 pixel

[carhun]

Hello!

How can I shift curve by 1 pixel?

I try to do in this way, but this doesn't help: I have QVector<QPointF> and than I do smth like:

for (int i = 0; i < sample.size(); i++) {
    tmp = samples.at(i);
 
    newVector.append(tmp.x, tmp.y - 1);
}
setSamples(newVector);

for (int i = 0; i < sample.size(); i++) {
    tmp = samples.at(i);

    newVector.append(tmp.x, tmp.y - 1);
}
setSamples(newVector);

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tmp there is struct like:
struct {
double x;
double y;
}

Problem is that scale is to big: 0 - 8*10^8
and when curves have same value i need some value shift down by 1 pixel...

[Spitfire]

problem is that single value unit quite likely doesn't represent single pixel on the screen.
If you have point ( 500, 20000 ) changing it to ( 500, 19999 ) won't do any good.

You could reimplement QwtPlotCurve::draw() and introduce offset there using QPainter::translate( 1, 1 ) for example.

[carhun]

Sorry, but can U explain more how it help me if start of coordinate system will be on 1,1 ?

Now I have that all my graphics start at 0,0 ...

Thanks, I think I understand how it can help me...

If I will have some questions, Ill write here.