globals [HSB-color
         RGB-color
        ]

to go
  set HSB-color hsb hue saturation brightness      ; color specified in HSB spectrum
  ask patches with [pycor > 0]                     ; is displayed in the top half
    [set pcolor HSB-color]

  set RGB-color rgb rgb-red rgb-green rgb-blue     ; color specified in RGB spectrum
  ask patches with [pycor <= 0]                    ; is displayed in the bottom half
    [set pcolor RGB-color]
end
@#$#@#$#@
GRAPHICS-WINDOW
306
10
756
481
5
5
40.0
1
10
1
1
1

CC-WINDOW
4
287
299
391
Command Center

BUTTON
11
17
127
50
go
go
T
1
T
OBSERVER
T

SLIDER
155
10
282
43
hue
hue
0.0
1.0
0.0
0.01
1
NIL

SLIDER
155
53
282
86
saturation
saturation
0.0
1.0
0.0
0.01
1
NIL

SLIDER
155
96
282
129
brightness
brightness
0.0
1.0
0.0
0.01
1
NIL

SLIDER
155
155
282
188
rgb-red
rgb-red
0.0
1.0
0.0
0.01
1
NIL

SLIDER
155
198
282
231
rgb-green
rgb-green
0.0
1.0
0.0
0.01
1
NIL

SLIDER
155
241
282
274
rgb-blue
rgb-blue
0.0
1.0
0.0
0.01
1
NIL

MONITOR
6
81
131
130
Color in top half
hsb-color
5
1

MONITOR
6
225
131
274
Color in bottom half
rgb-color
5
1

@#$#@#$#@
WHAT IS IT
----------
This is a simple example of the HSB (hue, saturation, brightness) and RGB (red, gren, blue) primitives.

To use it, simply press GO.  The top three sliders specify a color in the HSB spectrum which is displayed in the top half of the screen, while the bottom three sliders specify a color in the RGB spectrum which is displayed in the bottom half of the screen.  The two monitors show the actual NetLogo color, in the range of 0 to 140, that is actually displayed.
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default
true
0
Polygon -7566196 true true 150 5 40 250 150 205 260 250

@#$#@#$#@
NetLogo 2.0beta4
@#$#@#$#@
set hue 0.32
set saturation 0.25
set brightness 0.41
set rgb-red 0.57
set rgb-green 0.33
set rgb-blue 0.84
go
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@#$#@#$#@