to setup                
  ca                          ; clears all patch and turtle variables, and sets the graphics window to black.
  create-turtles 500          ; creates 500 turtles in the center of the screen
  ask turtles [
    rt random-float 360             ; sets heading of turtles to a random direction
    setxy random screen-size-x      ; place turtles randomly
          random screen-size-y
  ]
end

to go
  ask turtles [
    set heading 270
    fd 1
    ; Each turtle sets its color according to its x-coordinate.
    ; As its x-coordinate approaches the left side of the screen, 
    ; the turtle becomes darker.
    ; As its x-coordinate moves to the right side of the screen, 
    ; the turtle becomes lighter
    set color scale-color shading xcor (- screen-edge-x) (screen-edge-x)
    ]
end
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GRAPHICS-WINDOW
308
10
618
341
12
12
12.0
1
10
1
1
1

CC-WINDOW
5
155
302
330
Command Center

BUTTON
76
63
131
96
NIL
setup
NIL
1
T
OBSERVER

BUTTON
134
63
189
96
go
go
T
1
T
OBSERVER

SLIDER
51
102
209
135
shading
shading
0.0
140.0
105.0
1.0
1
NIL

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WHAT IS IT?
-----------
This code example demonstrates the scale-color reporter.  As a turtle's x-coordinate becomes larger,the turtle acquires a brighter color. Similarly, as a turtle's x-coordinate becomes smaller, the turtle acquires a darker shade.  The center of the graphics window is (0,0).
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default
true
0
Polygon -7566196 true true 150 5 40 250 150 205 260 250

arrow
true
0
Polygon -7566196 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150

box
true
0
Polygon -7566196 true true 45 255 255 255 255 45 45 45

circle
true
0
Circle -7566196 true true 35 35 230

person
false
0
Circle -7566196 true true 155 20 63
Rectangle -7566196 true true 158 79 217 164
Polygon -7566196 true true 158 81 110 129 131 143 158 109 165 110
Polygon -7566196 true true 216 83 267 123 248 143 215 107
Polygon -7566196 true true 167 163 145 234 183 234 183 163
Polygon -7566196 true true 195 163 195 233 227 233 206 159

spacecraft
true
0
Polygon -7566196 true true 150 0 180 135 255 255 225 240 150 180 75 240 45 255 120 135

thin-arrow
true
0
Polygon -7566196 true true 150 0 0 150 120 150 120 293 180 293 180 150 300 150

truck-down
false
0
Polygon -7566196 true true 225 30 225 270 120 270 105 210 60 180 45 30 105 60 105 30
Polygon -8716033 true false 195 75 195 120 240 120 240 75
Polygon -8716033 true false 195 225 195 180 240 180 240 225

truck-left
false
0
Polygon -7566196 true true 120 135 225 135 225 210 75 210 75 165 105 165
Polygon -8716033 true false 90 210 105 225 120 210
Polygon -8716033 true false 180 210 195 225 210 210

truck-right
false
0
Polygon -7566196 true true 180 135 75 135 75 210 225 210 225 165 195 165
Polygon -8716033 true false 210 210 195 225 180 210
Polygon -8716033 true false 120 210 105 225 90 210

turtle
true
0
Polygon -7566196 true true 138 75 162 75 165 105 225 105 225 142 195 135 195 187 225 195 225 225 195 217 195 202 105 202 105 217 75 225 75 195 105 187 105 135 75 142 75 105 135 105

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NetLogo 2.0alpha1
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