Unity3d判断一个点是否在多边形内

C#版本 

public static bool ContainsPoint(Vector2[] polyPoints, Vector2 p)
    {
        var j = polyPoints.Length - 1;
        var inside = false;
        for (int i = 0; i < polyPoints.Length; j = i++)
        {
            var pi = polyPoints[i];
            var pj = polyPoints[j];
            if (((pi.y <= p.y && p.y < pj.y) || (pj.y <= p.y && p.y < pi.y)) &&
                (p.x < (pj.x - pi.x) * (p.y - pi.y) / (pj.y - pi.y) + pi.x))
                inside = !inside;
        }
        return inside;
    }

JS版 

static function ContainsPoint (polyPoints : Vector2[], p : Vector2) : boolean { 
   var j = polyPoints.Length-1; 
   var inside = false; 
   for (i = 0; i < polyPoints.Length; j = i++) { 
      if ( ((polyPoints[i].y <= p.y && p.y < polyPoints[j].y) || (polyPoints[j].y <= p.y && p.y < polyPoints[i].y)) && 
         (p.x < (polyPoints[j].x - polyPoints[i].x) * (p.y - polyPoints[i].y) / (polyPoints[j].y - polyPoints[i].y) + polyPoints[i].x)) 
         inside = !inside; 
   } 
   return inside; 
}