Unsolved QWT transform coordinates to pixels
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Hi,
I duplicate my question from QtCenter because the problem wasn't solved yet.
I'm going to use QLinearGradient to fill area between my_line and some baseline like on the second plot from here. To do this I need to know position of every point of my_line in pixels.
QwtPlot::canvasMap(int axisId) says: Map for the axis on the canvas. With this map pixel coordinates can translated to plot coordinates and vice versa.
I can't anderstand which one translate or invTranslate perform the rescaling from axes (x,y) coordinate units to pixels but I tried to use them both:QwtScaleMap xMap = ui->qwtPlot->canvasMap(QwtPlot::xBottom); // input parameter type is "axisid" is QwtPlot::yLeft correct? QwtScaleMap yMap = ui->qwtPlot->canvasMap(QwtPlot::yLeft); double x2 = xMap.transform(1000.0); double y2 = yMap.transform(1000.0);
And I get the x2 and y2 numbers that are bigger than my QMainWindow size in QDesigner.
By the way the QwtPlot widget in QDesigner has axes limits from 0 to 1000 and after I draw the curve the limits become about from 0 to 3. How to transform axes coordinates to pixels after I draw the curve?
I'm working on that few days and all my ideas leaked out.
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Hi
Qwt is not an official Qt Component so you might not get any answers here (if nobody uses it )
and in that case, I would try the QWT mailing lists. -
@mrjj you are right
I tried to use mailing list yesterday but didnt understood how to do that :)
After you wrote I found in Internet how to use mailing list and just created it
Thank you :)