Popup HUD - part 1 of 2

;; model version 1.0,  June 16, 2022

extensions [ ls ]
globals [
          ;;============= HUD related golbals
          HUD         ;; model-ID reference
          HUD-state   ;; none, idle, ready
          safety-delay-seconds;; wait time after an update, possibly not needed


          ;;============== variables in my main model
          ;;   named differently from the HUD so it's clear which is which
          number-T
          size-T
          shape-T
]

to setup
  clear-all

  ;; ====== HUD RELATED commands
  set HUD-state "none"
  set safety-delay-seconds 0

  ;; ======= normal model commands
  ;; local version of these variables
  set number-T 3
  set size-T 3
  set shape-T "circle"


  create-turtles number-T [
      set size  size-T
      set shape shape-T
      set xcor random-xcor
      set ycor random-ycor
    ]

  reset-ticks
end 

to go
  if not ( HUD-state = "none") [ check-HUD ]   ;; The only HUD command in the GO loop

  ;; === usual model commands go next
  ask turtles [ set heading random 360 forward 1 ]

  tick
end 

;; ========= HUD related CODE begins here ====================================
;;
;; NOTE:  all the subroutines are named -HUD
;;
;;        "HUD" is not a magic word.  The Head's Up Display could
;;        be called "apple" everywhere on both ends and this would still run.
;;
;; NOTE:  all HUD interactions are driven by the model
;;        the HUD never asks the model to do anything.
;;        IN fact, the HUD has zero LevelSpace code in it and
;;        doesn't even list the "ls" extension.

;;  inbound commands, getting data FROM the HUD are like this:
;;    substituting your values for "< something > "
;;
;;  pattern: set  [ HUD-variable ] ls:of HUD
;;  example:  set size-T    [size-of-turtles ]   ls:of HUD
;;
;;   outbonund commands, setting a HUD variable from the model are like this:
;;   pattern:  ls:assign HUD   
;;   example:  ls:assign HUD status "idle"
;;
;;  or to run a HUD subroutine from the model
;;  pattern:    ls:ask HUD [ < hud subroutine name > ]
;;  example:    ls:ask HUD [ mark-update-complete ]

to check-HUD
   set HUD-state  [status] ls:of HUD
   ;print (word "HUD-state is " HUD-state)
   if HUD-state = "ready"
     [
       set number-T  [number-of-turtles ] ls:of HUD
       set size-T    [size-of-turtles ]   ls:of HUD
       set shape-T   [shape-of-turtles ]  ls:of HUD
       ask turtles [die]
       create-turtles number-T[
          set size  size-T
          set shape shape-T
          set xcor random-xcor
          set ycor random-ycor
       ]
       ls:assign HUD status "idle"
       set HUD-state  [status] ls:of HUD
      ls:ask HUD [ mark-update-complete ]
     ]
    wait safety-delay-seconds
end 

to  start-HUD  ;; ?? are there dead models ???
  if not ( HUD-state = "none") [ print "Destroying current HUD and starting fresh."]
  ls:reset
  startup-HUD
  setup-HUD
  check-HUD
end 

to startup-HUD
  ;; this code expects callable-HUD.nlogo to be in the same directory as this model
  ;; if that is not true the path in the following line needs to be adjusted
  ls:create-interactive-models 1 "./callable-HUD.nlogo"
  set HUD last ls:models
end 

to setup-HUD
  ls:ask HUD [ setup ]   ; calls setup in all models in LevelSpace
  ls:assign HUD status "idle"
  reset-ticks ; now we're ready to go, so reset ticks
end 

to show-HUD
  ifelse  not (HUD-state = "none") [ ls:show HUD ][ print "There is no HUD to show!"]
end 

to hide-HUD
    ifelse  not (HUD-state = "none") [ ls:hide HUD ][ print "There is no HUD to hide!"]
end 

to remove-HUD
    ifelse  not (HUD-state = "none") [
      ls:close HUD
      set HUD-state "none"
    ][ print "There is no HUD to remove!"]
end 

;; =========================== HUD RELATED CODE ENDS =========================

;  carefully [] might come in handy



; Public Domain:
; To the extent possible under law, Uri Wilensky has waived all
; copyright and related or neighboring rights to this model.