Replaying a QPicture, coordinate transformations
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When I draw something in a QPicture, like in the "example in the documentation":http://doc.qt.nokia.com/4.7-snapshot/qpicture.html#details:
@ QPicture picture;
QPainter painter;
painter.begin(&picture); // paint in picture
painter.drawEllipse(10,20, 80,70); // draw an ellipse
painter.end(); // painting done@and then replay it on another target, can I apply coordinate transformations before replaying the picture (like in the following), and will they have effect?
@ painter.begin(&myImage); // paint in myImage
painter.rotate(180.0);
painter.drawPicture(0, 0, picture); // draw the picture at (0,0)
painter.end(); // painting done@Besides, what is the performance impact of storing draw commands in a QPicture? Does someone have experience here?
Best regards,
Jens
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OK, I tried it out.
Yes, coordinate transformations are applied. Yes, it is at least much faster than our code that initially creates the paint commands.
Best,
Jens