QPainter: Problem with drawing trajectory of a planet
Hi! I'm a novice in Qt development, so sorry for asking dumb questions.
I found some example in Qt that uses QPainter and altered it for my case. I tried to draw a trajectory of a planet which revolves around a "Sun" and I succeeded. The thing I'm stuck in is I don't know how to tell the program to clear the background in the beginning and then not to continue clearing it because I want to see the trajectory of the planet.
- I tried setAutofillBackground(true), but it doesn't suit me cause it clears background all the time.
- Then I tried
it does the same. If I turn clearing of background in both cases off , I get some messy imprint of my screen with different windows in it. Could you please give me an advice how to solve the problem?
Thanks in advance!
You may try to set "Qt::WA_OpaquePaintEvent":http://developer.qt.nokia.com/doc/qt-4.8/qt.html#WidgetAttribute-enum attribute, but I suggest you paint the trajectory on a pixmap and then use the paint event to draw the pixmap on your widget.
Ok. I'll try that. Thanks!