Rebuilds a linear path from the output to input points.
        
        :return     <QPainterPath>

def rebuildLinear(self):
        """ 
        Rebuilds a linear path from the output to input points.
        
        :return     <QPainterPath>
        """

        points = self.controlPoints()

        # create a simple line between the output and input points
        path = QPainterPath()
        path.moveTo(*points[0])
        path.lineTo(*points[-1])

        return path