Area Gradients Simulation

;;Title: Exam project
;; Student: Constant Patrice KODJA ADJOVI
;; S21
;; Model: This project goal is to implement the gradien paths based on the areas' elevation in altitude (gradlevel variable)
;; Please do reduce the ticks speed in order the experience slow move.

;;Notice: ;;Gradien_0_XPosition and Gradien_0_YPosition are values that provide an offset from min-pxcor and min-pycor.

breed [ originTurtles originTurtle ]  ;; Turtle to be placed at the most min point (area with lower gradien)
breed [ fieldTurtles fieldTurtle ]  ;; Turtles in the field which will run to grafien 0 (gradlevel 0)

globals[
  optPt-xcor optPt-ycor  ;; min point of gathering
  patchCurrXcor patchCurrYcor  ;; This is to keep track with the turtles move in relation with the area elevation.
  countrestfieldturtles ;; for counting non-dying fieldTurtles
  dyingTurtles ;; number of dead fieldTurtles
]

patches-own [
  gradlevel   ;; area geographicla elevation
]

turtles-own [
]

to setup
  clear-all
  set countrestfieldturtles 0 ;; set remaining fieldTurtles counter to 0

  create-originTurtles 1 [set xcor optPt-xcor
    set ycor optPt-ycor set hidden? true] ;; Turtle 0 creation for world origin identification
                                          ;; Gradien_0_XPosition and Gradien_0_YPosition
                                          ;; are values that provide an offset from min-pxcor and min-pycor.
                                          ;; originTurtle 0 is hidden in oorder to let the red patch appear.

  set patchCurrXcor 0  ;; turtle patch position initialization
  set patchCurrYcor 0

  post-setup ;; to create and point a turtle to the origin

  set optPt-xcor min-pxcor + Gradien_0_XPosition ;; select the origin point at the minimum point of the area elevation
  set optPt-ycor min-pycor + Gradien_0_YPosition

  ask patch optPt-xcor optPt-ycor [ask neighbors [ set pcolor white ] set gradlevel 0 set pcolor red] ;; color origin patch's turtle's
                                                                                      ;; neighbors in WHITE

  ;;post-setup ;; to create and point a turtle to the origin

  reset-ticks
end 

to post-setup
  patches-elevation  ;; To assign area elevation to each patch by feeling it local variable grad-level

  ask patch optPt-xcor optPt-ycor [set gradlevel 0]

  create-fieldTurtles TotTurtlesNum [
    set xcor random-pxcor
    set ycor random-pycor
    ;;set color yellow
    set size 2
    set shape "arrow"
    pen-down
    facexy optPt-xcor optPt-ycor
  ]
end 

to patches-elevation
  let totpatches (max-pxcor * max-pycor)

  ask patches [
    let elevation random totpatches
    let elev% ceiling ( (elevation / totpatches) * 100 )

    if elevation != 0 [
      set gradlevel elevation
      ;;set pcolor scale-color basefieldcolor 10 50 5 ;; is a color
      if ( (elev% >= 95) and (elev% <= 100) ) [set pcolor basefieldcolor + 1.17 ]
      if ( (elev% >= 75) and (elev% < 95) ) [set pcolor (basefieldcolor + 1.2) ]
      if ( (elev% >= 50) and (elev% < 75) ) [set pcolor (basefieldcolor + 1.3) ]
      if ( (elev% >= 20) and (elev% < 50) ) [set pcolor (basefieldcolor + 1.4) ]
      if ( (elev% > 00) and (elev% < 20) ) [set pcolor (basefieldcolor + 1.5) ]
      ;;if (elev% = 00) [set pcolor white ]

      show gradlevel
      show elev%
    ]
]
end 

to go

  ;;setup ;; to force running setup procedure first

  set countrestfieldturtles count fieldTurtles  ;; fieldTurtles counting
  set dyingTurtles TotTurtlesNum - countrestfieldturtles

  ask fieldTurtles [

    ask patch optPt-xcor optPt-ycor [ask neighbors [ set pcolor white ]
     set gradlevel 0 set pcolor red] ;; color origin patch's turtle's neighbors in WHITE

    savePatchXY  ;; to save the current turtle position
                 ;; in order to compare it to the next position
                 ;; and see if the turtle will come back to it
                 ;; if the min elevation <= the same

    show "Below former pxcor and pycor"
    show patchCurrXcor show patchCurrYcor ;; for checking

    move-to min-one-of neighbors [gradlevel]  ;; Move the turtle onto
                                              ;; the lowest elevation within its close patches

    savePatchXY  ;; To save the new coordinates after "min-one-of neighbors"

    ask neighbors [set pcolor green] ;; color the turtle close patches

    show "Below after move pxcor and pycor"
    show pxcor show pycor ;; for checking

    show "Area (patch) altitude value (area elevation)"
    show gradlevel

    minPointNeigborhood ;; procedure for turtle's death if the most min point (area) is reached

    facexy optPt-xcor optPt-ycor  ;; To allow the turtle to always point to
                                            ;; the general min point (2,2)
    if (patchCurrXcor = pxcor and patchCurrYcor = pycor)
      [ fd 3 minPointNeigborhood ] ;; move to 3 steps away in order to avoid having the former low elevation
             ;; within it close patches if by the that value would ne lower than the next one
             ;; and will force the turtle to come back to it's former position

    ;;ask patch optPt-xcor optPt-ycor [ask neighbors [ set pcolor white ] set gradlevel 0 set pcolor red] ;; color origin patch's turtle's
                                                                                      ;; neighbors in WHITE

  ]
  ask patch optPt-xcor optPt-ycor [ask neighbors [ set pcolor white ]
    set gradlevel 0 set pcolor red] ;; color origin patch's turtle's neighbors in WHITE

  tick
  if ticks = Stop_ticks_Num [ beep stop ] ;; Stops the steps counter and emits a sound to indicate the simulation end
end 

to savePatchXY
  set patchCurrXcor pxcor ;; update the global variables with the current turtle position
  set patchCurrYcor pycor
end 


;; to check if the turtle's patch is within the close patch's neighbors of the most min point (area)
;;and if so, turtle can die

to minPointNeigborhood
  if ( (pxcor = optPt-xcor and pycor = optPt-ycor) or gradlevel = 0 )
      [ show "The most min point is reached (-grad)"
         die ] ;; If general min point (area) is reached
                                                           ;;or area's altitude is 0, the turtle die
  ask originTurtle 0
  [if ( member? [pxcor] of fieldTurtles [pxcor] of neighbors ) [ die ]] ;; if a turtle arrives in origin neighborhood, it dies
end