Drones - Target Convergence

breed [drones drone]

breed [targets target]

drones-own [see_target signal at_site]

targets-own [drones_here]

to setup
  ca
  reset-ticks
  ask patches [ set pcolor white ]
  set-default-shape targets "circle"
  create-targets 1
  ask patch max-pxcor max-pycor [sprout-drones num_drones]
  ask drones [ set color blue
               set see_target False
               set signal "Inactive"
               set at_site False
               move_around
                ]
  ask targets [ set color green ]
end 

to go

  ; Each drone that is not at the target's site starts by scanning the environment within its sight range cone,
  ; if it sees the target, then, it changes the internal variable see_target from False to True
  ; if the communication is active then the drone activates the signal
  ask drones with [at_site = False] [ if any? targets in-cone sight_range amplitude_sight
                                        [ set see_target True
                                         if communication = True [set signal "Active"] ]
                                       ]

  ; If a drone that is not at the target's site sees the target, then, it implements the "seek"
  ; method of moving otherwise it  implements the "wander method of moving
  ask drones with [at_site = False] [ifelse see_target = True [seek] [wander]]

  ; The target counts the drones that have arrived at its location
  ask target 0 [set drones_here count drones-here]

  ; Plot the number of drones that have arrived at the target
  do_plot

  tick

  ; If all the drones have arrived stop the game
  if [drones_here] of target 0 = num_drones [stop]
end 

to wander
  ; Wander is the method for drones who do not have the target in sight

  ; When the communication is set to active...
  ifelse communication = True
  ;... then if there are any drones with an active signal
  ; move to the place of one of these drones, otherwise move around
  [ ifelse any? drones with [signal = "Active"] [ move-to one-of drones with [signal = "Active"] ] [ move_around ] ]
  ; When the communication is not set to active, the drone moves around
  [ move_around ]
end 

to move_around
  ; Move randomly on the world to search for the target
  ; future versions will change this method
  rt random 180
  fd max_step
end 

to seek
  ; The seek method expresses the seeking behavior where
  ; the drone has found the target location and moves to the target
  move-to target 0
end 

to do_plot
  set-current-plot "Number of Drones on Target"
  plot [drones_here] of target 0
end