package  
{
	import flash.geom.Vector3D;
	/**
	 * ...
	 * @author mas
	 */
	public class BezierSegment3D
	{
		public var a:Vector3D;
		public var b:Vector3D;
		public var c:Vector3D;
		public var d:Vector3D;
		
		public function BezierSegment3D($a:Vector3D, $b:Vector3D, $c:Vector3D, $d:Vector3D) 
		{
			a = $a;
			b = $b;
			c = $c;
			d = $d;
		}
		
		public function getValue($t:Number):Vector3D
		{
			var t:Number = $t;
			var ret:Vector3D = new Vector3D;
			ret.x = a.x * Math.pow((1 - t), 3) + 3 * b.x * t * Math.pow((1 - t), 2) + 3 * c.x * Math.pow(t, 2) * (1 - t) + d.x * Math.pow(t, 3);
			ret.y = a.y * Math.pow((1 - t), 3) + 3 * b.y * t * Math.pow((1 - t), 2) + 3 * c.y * Math.pow(t, 2) * (1 - t) + d.y * Math.pow(t, 3);
			ret.z = a.z * Math.pow((1 - t), 3) + 3 * b.z * t * Math.pow((1 - t), 2) + 3 * c.z * Math.pow(t, 2) * (1 - t) + d.z * Math.pow(t, 3);
			
			return ret;
		}
	}
}