/*
**  Usage:
**      inst = instance_farthest_from_point(x, y, object, n);
**
**  Arguments:
**      x, y      a point
**      object    an object_index, or keyword "all"
**      n         proximity
**
**  Returns:
**      inst      (n)th farthest instance id of type
**                (object) from the given point (x, y)
**                or keyword "noone" if none found.
**
**  copyright (c) 2006, John Leffingwell
**  www.planetxot.com
*/
var pointx,pointy,object,n,list,farthest;
pointx = argument0;
pointy = argument1;
object = argument2;
n = argument3;
n = min(max(1,n),instance_number(object));
list = ds_priority_create();
farthest = noone;
with (object) ds_priority_add(list,id,distance_to_point(pointx,pointy));
repeat (n) farthest = ds_priority_delete_max(list);
ds_priority_destroy(list);
return farthest;