---speakers.nlogo

NETLOGO

breeds [ lefts rights sums ]
turtles-own [ yvel-old yvel-new ypos-old ypos-new time ]
globals [ time-ticks listening-point ]

to setup
  ca
  set-default-shape turtles "circle"
  ;; Create the turtles that represent the waves
  ;; We need three lines across the screen, so it sets
  ;; their xcor based on their incrementing turtle id
  cct-lefts screen-size-x [
        set xcor ( who - screen-edge-x )
        set color yellow ]
  cct-rights screen-size-x [
      set xcor ( who - screen-edge-x )
      set color cyan ]
  cct-sums screen-size-x [
      set xcor ( who - screen-edge-x )
      set color red ]

  ;; Initialize all variables to zero.  All of the turtles are stationary.
  set listening-point 0
  set time-ticks 0
  ask turtles
  [
    set yvel-old  0
    set ypos-old  0
    set time  0
  ]

  ;; The ends of the waves are special.  One side drives the wave, while
  ;; the other side anchors the waves- (prevents wrapping)
  ;; First define the driving turtles, which are colored green.
  ;; Next define the anchor turtles, which are colored blue
  ask lefts [
    if  ( xcor = screen-edge-x )  [
      set color blue
    ]
    if ( xcor = (- screen-edge-x) ) [
      set color green
    ]
  ]
  ask rights [
    if  ( xcor = (- screen-edge-x) ) [
      set color blue
    ]
    if ( xcor = screen-edge-x ) [
      set color green
    ]
  ]

  ;; draw the speakers, gray centered line, and listening point
  ask patches [
    if pycor = 0
      [ set pcolor gray ]
    draw-left-speaker
    draw-right-speaker
    if ( pxcor = listening-point and pycor > 0 and pycor < 4 )
      [ set pcolor white ]
  ]

  setup-plot
end


to go
  ;; Increase the model time
  set time-ticks time-ticks + 1

  ;; Move all the wave turtles
  ask turtles [
    if  ( color = green )
      [ drive-force ]
    if  ( color = yellow or color = cyan )
      [ driven-force ]
    if  ( color = blue )
      [ update ]
    if  ( color = red )
      [ interfere ]
  ]

  ;; Update the plot
  if  ( plot? ) [
    get-a-point
    plot-the-point
  ]

  ;; Reset the velocities
  ask turtles [
    set yvel-old yvel-new
    set ypos-old ypos-new
  ]

  ;; Check if a hide/show switch changed
  show-or-hide
end


to drive-force ;; procedure for green turtles
  set time time + 1
  ifelse (breed = lefts)
    [ set ypos-new amplitude-left * ( sin (frequency-left * 0.1 * time )) ]
    [ set ypos-new amplitude-right * ( sin (frequency-right * 0.1 * time )) ]
  set ypos-old ypos-new
  set ycor ypos-new
end

to driven-force ;; procedure for yellow and cyan turtles
  set yvel-new yvel-old + ( ypos-old-of turtle ( who - 1 ) )
                      - ypos-old  +  ( ypos-old-of turtle ( who + 1 ) ) - ypos-old
  set yvel-new ( ( 1000 - friction ) / 1000 ) * yvel-new
  set ypos-new ypos-old + yvel-new
  set ycor ypos-new
end

to update ;; procedure for blue turtles
  ifelse ( breed = lefts )
    [ set ypos-new ypos-old-of turtle ( who - 1 ) ]
    [ set ypos-new ypos-old-of turtle ( who + 1 ) ]
  set ycor ypos-new
end

to interfere ;; procdure for red turtles
  set ypos-new ( ( ypos-new-of turtle ( who - screen-size-x ) )
              + ( ypos-new-of turtle ( who - ( 2 * screen-size-x ) ) ) )
  set ycor ypos-new
  ifelse (( abs ypos-new ) <= screen-edge-y) and show-sum?
    [ showturtle ]
    [ hideturtle ]
end

to setup-plot
  set-current-plot "Speaker amplitude"
  clear-plot
  set-current-plot-pen "left"
  set-plot-pen-color yellow
  set-current-plot-pen "right"
  set-plot-pen-color cyan
  set-current-plot-pen "sum"
  set-plot-pen-color red
  set-plot-y-range ( ( - amplitude-left ) - amplitude-right ) ( amplitude-left + amplitude-right )
  set-plot-x-range 0 250
  auto-plot-on
end

to plot-the-point
  if ((time-ticks mod 200) = 0)
    [
      ifelse (not show-only-recent-plot?)
        [ set-plot-x-range 0 (time-ticks + 200) ]
        [ set-plot-x-range (time-ticks - 210) (time-ticks + 210)]
    ]

  set-current-plot-pen "left"
  if show-left? and any? lefts with [ round xcor = listening-point ]
    [ plotxy time-ticks ypos-new-of random-one-of lefts with [ round xcor = listening-point ] ]

  set-current-plot-pen "right"
  if show-right? and any? rights with [ round xcor = listening-point ]
   [ plotxy time-ticks ypos-new-of random-one-of rights with [ round xcor = listening-point ] ]

  set-current-plot-pen "sum"
  if show-sum? and any? sums with [ round xcor = listening-point ]
      [ plotxy time-ticks ypos-new-of random-one-of sums with [ round xcor = listening-point  ] ]
end

to get-a-point
  ;; Changes the listening-point if the mouse is down
  if mouse-down? [
    ask patches with [ pxcor = listening-point and pycor > 0 and pycor < 4 ]
      [ set pcolor black ]
    set listening-point round mouse-xcor
    ask patches with [ pxcor = listening-point and pycor > 0 and pycor < 4 ]
      [ set pcolor white ]
  ]
end

to draw-right-speaker ;; patch procedure
  if ( pxcor = screen-edge-x ) and ( pycor > ( -0.1 * screen-edge-x ) ) and ( pycor < ( 0.1 * screen-edge-x ) )
  [
    set pcolor orange
  ]
  if ( pxcor = round ( 0.9 * screen-edge-x ) ) and ( pycor > ( -0.2 * screen-edge-x ) ) and ( pycor < ( 0.2 * screen-edge-x ) )
  [
    set pcolor orange
  ]
end

to draw-left-speaker ;; patch procedure
  if ( pxcor = ( - screen-edge-x ) ) and ( pycor > ( -0.1 * screen-edge-x ) ) and ( pycor < ( 0.1 * screen-edge-x ) )
  [
    set pcolor orange
  ]
  if ( pxcor = round ( - ( 0.9 * screen-edge-x ) ) ) and ( pycor > ( -0.2 * screen-edge-x ) ) and ( pycor < ( 0.2 * screen-edge-x ) )
  [
    set pcolor orange
  ]
end

to show-or-hide
    ;; The sums are hidden in the interference procedure because it has the possibility
    ;; of wrapping when the sum amplitudes are too large.
    ifelse show-left?
      [
        if any? lefts with [ hidden? ]
          [ ask lefts [ st ] ]
      ]
      [
        if any? lefts with [ not hidden? ]
          [ ask lefts [ ht ] ]
      ]

     ifelse show-right?
      [
        if any? rights with [ hidden? ]
          [ ask rights [ st ] ]
      ]
      [
        if any? rights with [ not hidden? ]
          [ ask rights [ ht ] ]
      ]
end

; *** NetLogo 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 1998 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 project:
; PARTICIPATORY SIMULATIONS: NETWORK-BASED DESIGN FOR SYSTEMS LEARNING IN
; CLASSROOMS.  The project gratefully acknowledges the support of the
; National Science Foundation (REPP program) -- grant number REC #9814682.
; Converted from StarLogoT to NetLogo, 2002.  Updated 2002.
;
; To refer to this model in academic publications, please use:
; Wilensky, U. (1998).  NetLogo Speakers model.
; http://ccl.northwestern.edu/netlogo/models/Speakers.
; Center for Connected Learning and Computer-Based Modeling,
; Northwestern University, Evanston, IL.
;
; In other publications, please use:
; Copyright 1998 by Uri Wilensky.  All rights reserved.  See
; http://ccl.northwestern.edu/netlogo/models/Speakers
; for terms of use.
;
; *** End of NetLogo Model Copyright Notice ***
@#$#@#$#@
GRAPHICS-WINDOW
323
10
817
445
60
50
4.0
1
10
1
1
1
0
0
0
1

CC-WINDOW
5
556
826
651
Command Center
0

BUTTON
85
10
159
43
go
go
T
1
T
OBSERVER
T
NIL

BUTTON
11
10
85
43
setup
setup
NIL
1
T
OBSERVER
T
NIL

SLIDER
15
99
147
132
amplitude-left
amplitude-left
0
50.0
12.0
1
1
NIL

SLIDER
176
11
308
44
friction
friction
0
100.0
0.0
1
1
NIL

SLIDER
15
66
147
99
frequency-left
frequency-left
1
100.0
71.0
1
1
NIL

MONITOR
16
144
113
193
listening-point
listening-point
3
1

SWITCH
212
474
316
507
plot?
plot?
0
1
-1000

PLOT
9
199
311
459
Speaker amplitude
Time
Amplitude
0.0
250.0
-61.0
50.0
false
true
PENS
"left" 1.0 0 -1184463 true
"right" 1.0 0 -11221820 true
"sum" 1.0 0 -2674135 true

SWITCH
11
474
209
507
show-only-recent-plot?
show-only-recent-plot?
0
1
-1000

SWITCH
10
509
122
542
show-left?
show-left?
0
1
-1000

SWITCH
245
509
362
542
show-right?
show-right?
1