// -*- C -*-

module FArcSegment_mask(beta) {
  for (i=[0 : 0.75 : 3]) {
    rotate(i*beta/4)
      polygon([[0, 0],
	       [1, 0],
	       [cos(beta), sin(beta)]]);
  }
}

module FArcSegment(xc,yc,inrad,outrad,alpha,delta) {
  translate(xc,yc) {
    intersection() {
      difference() {
	circle(r=outrad);
	circle(r=inrad);
      }
      rotate(alpha) scale(outrad*2) {
	FArcSegment_mask(delta);
      }
    }
  }
}

FArcSegment(10,10, 20,30, 20,10);