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verburg
23rd January 2009, 00:32
Hey guys,

Would anyone know why this works:


QPainter painter(obj);
painter.setWorldTransformation(...);
..
const QTransform & xform = painter.transform();
QPoint pt1 = xform.map(QPoint(x1, y1));
QPoint pt2 = xform.map(QPoint(x2, y2));

painter.save();
painter.setWorldTransform(QTransform());
painter.drawLine(pt1, pt2);
painter.restore();

but doing it directly does not:


QPainter painter(obj);
painter.setWorldTransformation(...);
..
painter.drawLine(x1, y1, x2, y2);

?

I got drawRect to work with this transform, but I cannot get lines to behave. I've been all over the QPainter, QPen, and QTransform docs, but I haven't found anything to explain this.

Thanks,
-Chris