I suspect there's a way to do it by somehow drawing the straight lines in the glyphs as curves and pulling the off-curve points various distances away from being collinear with the on-curve points, in one direction or another, as I change the position of those on-curve points.
But, I still struggle to figure out how to tell which are which, in a list of a curve's points, or to write a set of on-curve and off-curve points to a curve to create a shape on purpose—I know what quadratic and cubic curves are, but the order/syntax of the points in the path escapes me. So it may be a long while before I figure anything out …