package com.greensock.easing {
    public class Sine {
        private static const _HALF_PI:Number = Math.PI * 0.5;
        
        public static function easeIn (t:Number, b:Number, c:Number, d:Number):Number {
            return -c * Math.cos(t/d * _HALF_PI) + c + b;
        }
        public static function easeOut (t:Number, b:Number, c:Number, d:Number):Number {
            return c * Math.sin(t/d * _HALF_PI) + b;
        }
        public static function easeInOut (t:Number, b:Number, c:Number, d:Number):Number {
            return -c*0.5 * (Math.cos(Math.PI*t/d) - 1) + b;
        }
    }
}