Conway's Game of Life with rule switching

patches-own [
  next-pcolor ;; the next state is calculated using current pcolor
]

;; clear the board and create some life

to setup
  clear-all
  reset-ticks

  ;; make the world with custom size
  resize-world 0 (world-size - 1) 0 (world-size - 1)

  ;; heuristic scaling of the patch size
  set-patch-size floor ( 50 / (sqrt world-size) )

  ;; use next-pcolor to initialize pcolor
  ask patches [
    ifelse random 100 < init-life [
      set next-pcolor black
    ][
      set next-pcolor white
    ]
    set pcolor next-pcolor
  ]
end 

;;
;; main function
;;

to go

  ifelse synchronous [
    ask patches [
      simulate-life
    ]
    ask patches [
      update-state
    ]
  ][
    ask patches [
      simulate-life
      update-state
    ]
  ]

  tick
end 

;;
;; calculate the updating rule
;;

to  simulate-life
  ifelse deterministic [ ;; deterministic rule switching
    ifelse ticks mod deterministic-period = 0 [
      update-rule-modified
    ][ ;; ticks mod deterministic-period \= 0
      update-rule-std
    ]
  ][ ;; random rule switching
    ifelse random-float 1 > rule-switch-prob [
      update-rule-std
    ][
      update-rule-modified
    ]
  ]
end 

;;
;; standard update rule for the Game of Life
;;

to update-rule-std
  let x (count neighbors with [ pcolor = black] )

  ifelse pcolor = black [
    ifelse x < 2 or x >= 4 [ ;; x>=4 (weak inequality) - standard rule
      set next-pcolor white ;; ie. die
    ][
      set next-pcolor black ;; ie. stay alive
    ]
  ][ ;; pcolor = white
    if x >= 3 and x < 4 [ ;; modified rule if second-threshold != 4
          set next-pcolor black ;; ie. birth
    ]
  ]
end 

;;
;; update rule with the altered treshold for the overpopulation
;;

to update-rule-modified
  let x (count neighbors with [ pcolor = black] )

  ifelse pcolor = black [
    ifelse x < 2 or x >= second-threshold [ ;; modified rule if second-threshold != 4
      set next-pcolor white ;; ie. die
    ][
      set next-pcolor black ;; ie. stay alive
    ]
  ][ ;; pcolor = white
    if x >= 3 and x < second-threshold [ ;; modified rule if second-threshold != 4
          set next-pcolor black ;; ie. birth
    ]
  ]
end 

;;
;; update the state
;;

to update-state
  set pcolor next-pcolor
end 

;;
;; reporters
;;

;;
;; fraction of living cells
;;

to-report %living
  report 100 * ( count patches with [ pcolor = black] ) / ( count patches )
end