Hi
Well to get below the QWTPlot plot would
be QWTPlotptr->y() + QWTPlotptr->height()
However, a more solid approach could be to use a QLabel as
a canvas using a pixmap. That way, its very easy to position even if using layouts to make
GUI auto adjust to different screen sizes.
void PaintShapes()
{
// take size of label
int h = ui->label->height();
int w = ui->label->width();
// make a pixmap of the wanted size
QPixmap pix(w, h);
// assign painter to it so we can paint on it
QPainter paint(&pix);
// fill it
pix.fill( Qt::white );
// paint on canvas
paint.setPen(QColor(0, 0, 0, 255));
paint.drawRect(0, 0, w, h);
..other paint operations-..
// set the pixmap to the label so its shown.
ui->label->setPixmap(pix);
}