How can i draw a special HalfCircle in QGraphicsView?
i know how to draw a exact half circle in QGraphicsView, but what i want is that:
the "top" line can move from the top of the circle to the bottom,
and i found that inherite from QGraphicsEllipseItem is hard to realize this effect.
if there is no way to directly change the point postion of this special circle, can i use some mask to do this?and how?
what i want is like this pic below, but the "top line" can be anywhere in y axis but not only at the exact half position.