Activity 6: Barrier Bot

;
; rnd_drawer.kf
;
; Move around randomly, when user presses SPACE key, draw barrier blocks.
;
; Add this creature as any strain you want, with
; whatever energy you want.
; Make sure this strain is uneatable (EAT Mode = 5)
; Make sure this strain can MAKE-BARRIER
;

main:
{
    0       ; 0: current x
    0       ; 1: current y
    0       ; 2: mode

    {
        pick_direction call

        {
            check_key call
            2 PEEK { 0 PEEK 1 PEEK 2negate MAKE-BARRIER pop } if

            0 PEEK 1 PEEK OMOVE

            ?loop
        } call

        1 ?loop
    } call
}

pick_direction:
{
    -1 1 CHOOSE 0 POKE
    -1 1 CHOOSE 1 POKE
}

check_key:
{
    KEY-PRESS R0!
    R0 0 = { 0 2 POKE } if
    R0 32 = { 1 2 POKE } if
    R0 65 = { pick_direction call } if
}