  const p1 = subst.center; // assume artificial vertex has zero size
          const p2 = r.getPoint(2).copy();
          const p3 = r.getPoint(3).copy();
          const p5 = r.getPoint(r.pointsCount - 1);
          let dist = 10;
          if (subst.angle == 270 || subst.angle == 180) dist = -20;
          if (subst.angle == 90 || subst.angle == 270) {
            p2.y = p5.y - dist; // (p1.y+p5.y)/2;
            p3.y = p5.y - dist; // (p1.y+p5.y)/2;
          } else {
            p2.x = p5.x - dist; // (