It seems ellipses are not drawn correctly depending on the thickness of their pen.
In the picure below all the ellipses of equal shape are drawn with the same rect
The picture on the left shows the result using WPainter, the picture on the right shows
The shape of the ellipse in conjunction with the thickness of the pen seems to scale the
shape incorrecty. I suspect this is due to some miscalculation in related scaling in the
Thanks for posting all of this. I filed an issue report that seems related here: #8041.