Artificial Termites in StarLogo

The two procedures setup and go are equivalent to buttons found on the interface window. Go is a forever button which means the code will be repeated until the next button press. The variables number, density, and wiggle are controlled by sliders on the interface window.

to setup
 ca
 if (random 100) < density [setpc yellow]
 crt number
 setc red
 setxy random (screen-edge * 2) random (screen-edge * 2)
end

to go
 search-for-chip   ;; find a wood chip and pick it up
 find-new-pile     ;; find another wood chip
 find-empty-spot   ;; find a place to put down wood chip
end

to search-for-chip
 if pc = yellow    ;; if find a wood chip...
  [stamp black     ;; remove wood chip from patch
   setc orange     ;; turn orange while carrying chip
   jump 20
   stop]
 wiggle
 search-for-chip
end

to find-new-pile
 if pc = yellow [stop]   ;; if find a wood chip, stop
 wiggle
 find-new-pile
end

to find-empty-spot
 if pc = black      ;; if find a patch without a wood chip
  [stamp yellow     ;; put down wood chip in patch
   setc red         ;; set own color back to red
   get-away
   stop]
 seth random 360
 fd 1
 find-empty-spot
end

to get-away
 seth random 360
 jump 20
 if pc = black [stop]
 get-away
end

to wiggle
 fd 1
 rt random 50
 lt random 50
end

to startup
 ca
end

If there are requests I will make available an online reference manual to the Star logo language.