Wolf Sheep Benchmark

globals [ result ]
breed [ sheep a-sheep ]
breed [ wolves wolf ]
turtles-own [ energy prey ]
patches-own [ countdown ]

to benchmark
  random-seed 579
  setup
  reset-timer
  repeat 400 [ go ]
  set result timer
end 

to setup
  ca
  ask patches [ set pcolor green ]
  if grass? [
      ;; indicates whether the grass switch is on
      ;; if it is true, then grass grows and the sheep eat it
      ;; if it false, then the sheep don't need to eat
    ask patches [
      set countdown random grass-delay ;; initialize grass grow clocks randomly
      if (random 2) = 0  ;;half the patches start out with grass
          [ set pcolor brown ]
    ]
  ]

  create-ordered-sheep init-sheep  ;; create the sheep, then initialize their variables
  ask sheep
  [
    set color white
    set energy random-float (2 * sheep-metabolism)
    set shape "sheep"
    setxy random world-width random world-height
  ]

  create-ordered-wolves init-wolves  ;; create the wolves, then initialize their variables
  ask wolves
  [
    set color black
    set energy random-float (2 * wolf-metabolism)
    set shape "wolf"
    setxy random world-width random world-height
  ]

  if plot? [ graph ]
end 

to go
  ask sheep [
    move
    if grass? [
      set energy energy - 1  ;; deduct energy for sheep only if grass? switch is on
      eat-grass
    ]
    reproduce-sheep
    death
  ]
  ask wolves [
    move
    set energy energy - 1  ;; wolves lose energy as they move
    catch-sheep
    reproduce-wolves
    death
  ]
  if grass? [ ask patches [ grow-grass ] ]
  if plot? [ graph ] ;; plot populations
  tick
  if (count turtles = 0) [ stop ]
end 

to move  ;; turtle procedure
  rt random 50 - random 50
  fd 1
end 

to eat-grass  ;; sheep procedure
  ;; sheep eat grass, turn the patch brown
  if pcolor = green [
    set pcolor brown
    set energy energy + sheep-metabolism  ;; sheep gain energy by eating
  ]
end 

to reproduce-sheep  ;; sheep procedure
  if random-float 100 < sheep-reproduce [  ;; throw "dice" to see if you will reproduce
    set energy round (energy / 2 )   ;; divide energy between parent and offspring
    hatch 1 [ rt random 360 fd 1 ]   ;; hatch an offspring and move it forward 1 step
  ]
end 

to reproduce-wolves  ;; wolf procedure
  if random-float 100 < wolf-reproduce [  ;; throw "dice" to see if you will reproduce
    set energy round (energy / 2 )  ;; divide energy between parent and offspring
    hatch 1 [ rt random 360 fd 1 ]  ;; hatch an offspring and move it forward 1 step
  ]
end 

to catch-sheep  ;; wolf procedure
  set prey one-of sheep-here  ;;set prey to ID of one of the sheep in your patch
  if (prey != nobody) [              ;;check if prey represents a sheep (there is no sheep with ID = -1)
    ask prey [ set energy -1 ]       ;; sheep will then die on next tick
    set energy energy + wolf-metabolism    ;;get energy from sheep
  ]
end 

to death  ;; turtle procedure
  ;; when energy dips below zero, die
  if energy < 0 [ die ]
end 

to grow-grass  ;; patch procedure
  ;; countdown on brown patches, if reach 0, grow some grass
  if pcolor = brown [
    ifelse countdown <= 0
      [ set pcolor green
        set countdown grass-delay ]
      [ set countdown (countdown - 1) ]
  ]
end 

to graph
  set-current-plot-pen "sheep"
  plot count sheep
  set-current-plot-pen "wolves"
  plot count wolves
  if grass? [
    set-current-plot-pen "grass / 4"
    plot count patches with [ pcolor = green ] / 4  ;; divide by four to keep it within similar
                                                ;; range as wolf and sheep populations
  ]
end