wolf sheep predation w/mid-level focusing

globals [ watched-one ]

;; Sheep and wolves are both breeds of turtle.
breed [sheep a-sheep]  ;; sheep is its own plural, so we use "a-sheep" as the singular.
breed [wolves wolf]
breed [ flashes flash] ;; signifies a wolf eating a sheep

turtles-own [energy]       ;; both wolves and sheep have energy
patches-own [countdown]
flashes-own [ clock ]

to setup
  clear-all
  ask patches [ set pcolor green ]
  ;; check GRASS? switch.
  ;; if it is true, then grass grows and the sheep eat it
  ;; if it false, then the sheep don't need to eat
  if grass? [
    ask patches [
      set countdown random grass-regrowth-time ;; initialize grass grow clocks randomly
      set pcolor one-of [green brown]
    ]
  ]
  set-default-shape sheep "sheep-right"
  create-sheep initial-number-sheep  ;; create the sheep, then initialize their variables
  [
    set color white
    set size 1.5  ;; easier to see
    set label-color blue - 2
    set energy random (2 * sheep-gain-from-food)
    setxy random-xcor random-ycor
    if ( heading < 360 and heading >= 180 ) [ set shape "sheep-left"]
  ]
  set-default-shape wolves "wolf-right"
  create-wolves initial-number-wolves  ;; create the wolves, then initialize their variables
  [
    set color black
    set size 1.5  ;; easier to see
    set energy random (2 * wolf-gain-from-food)
    setxy random-xcor random-ycor
    if ( heading < 360 and heading >= 180 ) [ set shape "wolf-left"]
  ]
  set watched-one nobody
  if (watch-one != "none")
    [
      ifelse (watch-one = "sheep")
        [set watched-one one-of sheep ask watched-one [ watch-me]]
        [set watched-one one-of wolves ask watched-one [ watch-me]]      
    ]

  display-labels
  update-plot
end 

to go
  if not any? turtles [ stop ]
  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 ] ]
  ask flashes [ if clock = 0 [ die ] set clock clock - 1 ]
  if (I-exterminate != "none") [ wack ]
  tick
  update-plot
  display-labels
  if (watch-one != "none" and watched-one = nobody)
    [
      ifelse (watch-one = "sheep")
        [if count sheep > 0 [ set watched-one one-of sheep ask watched-one [ watch-me]]]
        [if count wolves > 0 [ set watched-one one-of wolves ask watched-one [ watch-me]]]  
    ]
end 

to move  ;; turtle procedure
  rt random 20
  lt random 20
  if (breed = sheep )
   [ ifelse ( heading < 360 and heading >= 180 ) [ set shape "sheep-left"] [ set shape "sheep-right" ]]
   if (breed = wolves)
   [ ifelse ( heading < 360 and heading >= 180 ) [ set shape "wolf-left"] [ set shape "wolf-right" ]]
  fd 0.2
end 

to eat-grass  ;; sheep procedure
  ;; sheep eat grass, turn the patch brown
  if pcolor = green [
    set pcolor brown
    set energy energy + sheep-gain-from-food  ;; 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 (energy / 2)                ;; divide energy between parent and offspring
    hatch 1 [ rt random-float 360 fd 1 ]   ;; hatch an offspring and move it forward 1 step
    if see-births? [ celebrate-sheep-birth ]
  ]
end 

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

to catch-sheep  ;; wolf procedure
  let prey one-of sheep-here                    ;; grab a random sheep
  if prey != nobody                             ;; did we get one?  if so,
    [ ask prey [ if see-deaths? [make-sheep-ghosts ]
      observe
;      ask prey [ 
;      if (watch-one = "sheep"  and who = ([who] of watched-one)) [ make-sheep-ghosts-watch-one ]]
      die ]                          ;; kill it
      set energy energy + wolf-gain-from-food 
;      if see-ghosts? [hatch 1 [set breed flashes set shape "ghost" set color yellow set size 1 set clock 2 ]
    ]
        ;; get energy from eating
end 

to death  ;; turtle procedure
  ;; when energy dips below zero, die
  if energy < 0 [ 
;                  if ((breed = sheep) and watch-one = "sheep"  and who = ([who] of watched-one)) [ make-sheep-ghosts-watch-one ]
;                  if ((breed = wolves) and watch-one = "wolf"  and who = ([who] of watched-one)) [ make-wolf-ghosts-watch-one ]
                  if see-deaths? [
                  ifelse (breed = sheep )
                    [ make-sheep-ghosts] [ make-wolf-ghosts ]]          
                   observe
                   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-regrowth-time ]
      [ set countdown countdown - 1 ]
  ]
end 

to wack
    if mouse-down? and mouse-inside? [
    ifelse (I-exterminate = "sheep")
      [ ask patch mouse-xcor mouse-ycor [ ask sheep in-radius exterminate-radius [ die ]]]
      [ifelse (I-exterminate = "wolves")
      [ask patch mouse-xcor mouse-ycor [ ask wolves in-radius exterminate-radius [ die ]] ]          
      [ask patch mouse-xcor mouse-ycor [ ask patches in-radius exterminate-radius [ set pcolor brown ]]]]]
end 

to observe
    if (
    (watched-one = nobody) and 
    (watch-one != "none"))
      [ ifelse ( watch-one = "sheep")
        [if count sheep > 0 [ set watched-one one-of sheep ask watched-one [ watch-me]] ]
        [if count wolves > 0 [ set watched-one one-of wolves ask watched-one [ watch-me]] ]
      ]
end 

to make-sheep-ghosts
  hatch 1 [set breed flashes set shape "ghost" 
      set color yellow set size 2 set clock 2 ]
end 

to make-wolf-ghosts
  hatch 1 [set breed flashes set shape "ghost" 
           set color red - 1 set size 2 set clock 2 ]
end 

to make-sheep-ghosts-watch-one
  hatch 1 [set breed flashes set shape "ghost" 
      set color yellow  set size 3 set clock 4 ]
end 

to make-wolf-ghosts-watch-one
  hatch 1 [set breed flashes set shape "ghost" 
      set color yellow set size 3 set clock 4 ]
end 

to celebrate-sheep-birth
  hatch 1 [set breed flashes set shape "circle 3"
           set color pink + 1 set size 2.5 set clock 3 ]
end 

to celebrate-wolf-birth
  hatch 1 [set breed flashes set shape "circle 3"
           set color cyan + 1 set size 2.5 set clock 3 ]
end 

to update-plot
  set-current-plot "populations"
  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 

to display-labels
  ask turtles [ set label "" ]
  if show-energy? [
    ask wolves [ set label round energy ]
    if grass? [ ask sheep [ set label round energy ] ]
  ]
end 


; *** NetLogo 4.0.2 Model Copyright Notice ***
;
; This model was created as part of the project: CONNECTED MATHEMATICS:
; MAKING SENSE OF COMPLEX PHENOMENA THROUGH BUILDING OBJECT-BASED PARALLEL
; MODELS (OBPML).  The project gratefully acknowledges the support of the
; National Science Foundation (Applications of Advanced Technologies
; Program) -- grant numbers RED #9552950 and REC #9632612.
;
; Copyright 1997 by Uri Wilensky.  All rights reserved.
;
; Permission to use, modify or redistribute this model is hereby granted,
; provided that both of the following requirements are followed:
; a) this copyright notice is included.
; b) this model will not be redistributed for profit without permission
;    from Uri Wilensky.
; Contact Uri Wilensky for appropriate licenses for redistribution for
; profit.
;
; This model was converted to NetLogo as part of the projects:
; PARTICIPATORY SIMULATIONS: NETWORK-BASED DESIGN FOR SYSTEMS LEARNING
; IN CLASSROOMS and/or INTEGRATED SIMULATION AND MODELING ENVIRONMENT.
; The project gratefully acknowledges the support of the
; National Science Foundation (REPP & ROLE programs) --
; grant numbers REC #9814682 and REC-0126227.
; Converted from StarLogoT to NetLogo, 2000.
;
; To refer to this model in academic publications, please use:
; Wilensky, U. (1997).  NetLogo Wolf Sheep Predation model.
; http://ccl.northwestern.edu/netlogo/models/WolfSheepPredation.
; Center for Connected Learning and Computer-Based Modeling,
; Northwestern University, Evanston, IL.
;
; In other publications, please use:
; Copyright 1997 Uri Wilensky.  All rights reserved.
; See http://ccl.northwestern.edu/netlogo/models/WolfSheepPredation
; for terms of use.
;
; *** End of NetLogo 4.0.2 Model Copyright Notice ***