code: function (polygon, x, y) {
  		var nn = polygon.length;
  		var prevIndex = nn - 2;
  		var inside = false;
  		for (var ii = 0; ii < nn; ii += 2) {
  			var vertexY = polygon[ii + 1];
  			var prevY = polygon[prevIndex + 1];
  			if ((vertexY < y && prevY >= y) || (prevY < y && vertexY >= y)) {
  				var vertexX = polygon[ii];
  				if (vertexX + (y - vertexY) / (prevY - vertexY) * (polygon[prevIndex] - vertexX) < x) inside = !inside;
  			}
  			prevIndex = ii;
  		}
  		return inside;
  	}
docs: Returns true if the polygon contains the point.