public static S2Cap fromAxisAngle(S2Point axis,S1Angle angle){
  double d=Math.sin(0.5 * angle.radians());
  return new S2Cap(axis,2 * d * d);
}

public static S2Cap fromAxisAngle ( S2Point axis , S1Angle angle ) { double d = Math . sin ( 0.5 * angle . radians ( ) ) ; return new S2Cap ( axis , 2 * d * d ) ; }
create a cap given its axis and the cap opening angle , i . e . maximum angle between the axis and a point on the cap . ' axis ' should be a unit - length vector , and ' angle ' should be between 0 and 180 degrees .
