docs: static double axisAdjustedDistanceSq(EllipseRotated_F64 a , EllipseRotated_F64 b ) {
  		double dx = b.center.x - a.center.x;
  		double dy = b.center.y - a.center.y;
  
  		double c = Math.cos(a.phi);
  		double s = Math.sin(a.phi);
  
  		// rotate into ellipse's coordinate frame
  		// scale by ratio of major/minor axis
  		double x = (dx*c + dy*s);
  		double y = (-dx*s + dy*c)*a.a/a.b;
  
  		return x*x + y*y;
  	}