def polygon(self):
print 'old rect ', self.pix.rect()
end_center = self.pix.rect().center()
print 'center ', end_center
rect = QtCore.QRect(QtCore.QPoint(0, 0) - end_center, end_center)
print 'new rect ', rect
return QtGui.QPolygon(rect)
old rect PyQt4.QtCore.QRect(0, 0, 50, 50)
center PyQt4.QtCore.QPoint(24, 24)
new rect PyQt4.QtCore.QRect(-24, -24, 49, 49)