package {

	/**
	 * @author nicoptere
	 */
	import flash.display.*;
	
	public class Repell extends Force
	{
		
		static public var STIFFNESS:Number = .01;
		private var angle:Number;
		
		public function Repell( X:Number, Y:Number )
		{
			
			super( X, Y );
			color = 0xFF0000;
			
		}
		
		override public function equation( v:Vector ):void
		{
			
			if(
					( v.x < x + R )
				&&	( v.x > x - R )
				&&	( v.y < y + R )
				&&	( v.y > y - R )
				
			){
				var dx:Number;
				var dy:Number;
				var dist:Number;
				
				//check the distance to emmitter
				dx = x - v.x;
				dy = y - v.y;
				
				dist = Math.sqrt( dx*dx + dy*dy );
				
				//if the distance is inferior to the radius
				if( dist < R )
				{
					angle = Math.atan2( dy, dx );
					
					//force adds its strength to alter the path
					v.vx += Math.cos( angle ) * -( R - dist ) * STIFFNESS;
					v.vy += Math.sin( angle ) * -( R - dist ) * STIFFNESS;
					
				}
			}
		}
		
		
	}
}