PLANE DEMO:

The following agents comprise the Plane demo:

world.lisp
plane.lisp
control.lisp

To run the demo, load the three agents.
The world demo requires macintosh graphics or xwindows
graphics.


Once the agents are loaded, go to the control
agent.

type
<CONTROL> request plane (do (+ now m) (be-at 200 100))

then type
<CONTROL> run

The Plane agent will slowly make its way to the location
(200,100).  The Plane agent can handle an arbitrary number
of requests to be at certain locations.  It will commit
to be anywhere it is requested to be by the control agent
as long as it believes it is capable of it.  Capability has
been implemented in this example in the private actions.
The Plane agent is capable of flying anywhere if it can
get there by the time it's requested to be there.  In the
simple case, a plane can't commit to be 500 units away from
where it is now in one second.  More complicated cases arise
where a plane can't commit to be one unit away from where it
is now ten minutes from now, because it has already committed
to be 400 units away from where it is now 9 minutes and 50 
seconds from now.  The functions cap-check and capable-of 
perform these checks.

