package
{
    import flash.display.Sprite;
 
    public class GridTest extends Sprite
    {
        private var _endNode:Node;
        private var _startNode:Node;
        private var _straightCost:Number=1.0;
        private var _diagCost:Number = 1.4;
 
 
        public function GridTest()
        {
            var g:Grid=new Grid(5, 5);
            g.setStartNode(0, 3);
            g.setEndNode(4, 1);
             
            _endNode = g.endNode;
            _startNode = g.startNode;
             
            var c1:Number = manhattan(_startNode);//8 
            var c2:Number = euclidian(_startNode);//4.47213595499958
            var c3:Number = diagonal(_startNode);//4.8
             
            trace(c1,c2,c3);
        }
 
        //曼哈顿估价法
        private function manhattan(node:Node):Number
        {
            return Math.abs(node.x - _endNode.x) * _straightCost + Math.abs(node.y - _endNode.y) * _straightCost;
        }
 
        //几何估价法
        private function euclidian(node:Node):Number
        {
            var dx:Number=node.x - _endNode.x;
            var dy:Number=node.y - _endNode.y;
            return Math.sqrt(dx * dx + dy * dy) * _straightCost;
        }
 
        //对角线估价法
        private function diagonal(node:Node):Number
        {
            var dx:Number=Math.abs(node.x - _endNode.x);
            var dy:Number=Math.abs(node.y - _endNode.y);
            var diag:Number=Math.min(dx, dy);
            var straight:Number=dx + dy;
            return _diagCost * diag + _straightCost * (straight - 2 * diag);
        }
    }
}