Lunar Lander

                                a program by
                                Michael Vinson

        
        Disengage from Service Module, land on a flat spot, plant a flag, take-
off, and, finally, rendezvous with the Service Module.  The version called 
NLANDER does NOT require the 8087 board, however it is noticeably slower than
LANDER (which does require the 8087).  I've only run it on a Rainbow 100A. 

        When you first run Lander, it asks you for a speed constant (with a
default value) and whether you want 'beginner version'--meaning only that
you can land faster safely, and less gravity (in any case these things are
settable using the 'e' command).  Then it displays an initial terrain.  Type
anything but 'r' if the terrain is ok, but if you don't like it, hit 'r' and
the program will generate a new one.  Continue until you find an acceptable 
terrain.  Then use the 'b' command to disengage, and you're on your way.

        The commands are:

        'z','x','c' : thrust, in varying amounts, 'c'=strongest.
        
        '<' : retrorockets, useful mainly in redocking.

        ' ' (space bar) : Upward thrust, regardless of orientation. Very
            handy but eats up the fuel.

        'n' : rotate left.

        'm' : rotate right.

        'b' : fires explosive bolts to disengage from the service module, or to
              help lifting off (only works when engaged or landed).

        'f' : plant flag! (only works when landed).

        ',' : computer projection of your trajectory.

        'e' : allows you to set some parameters, like max allowable landing
              speed, gravity, viscosity, etc.

        'd','t','y','u','i' : change the colors.

        'a' : pause game.

        'r' : new game.

        's' : new ship, old terrain.

        '+' : restores all fuel and damage (for cheaters only).

        'q' : quit.


        There is also an alternate set of controls on the right side of the
keyboard, using the arrow keys and the number pad in an arrangement analogous
to the above.  

        When landing, don't forget to kill off horizontal velocity as well as
vertical.  You can only land pointing straight up, and to rendezvous with the
Service Module, you must be pointing to the right.  

        Any questions or comments can be addressed to

                Michael Vinson
                2817 Ashby Ave.
                Berkeley,  CA 94705

        Or, through CompuServe. My number is 73537,2466.

        I have several more games along these lines, if anyone is interested.