SaturationBrightnessPicker
The SaturationBrightnessPicker control allows for the input of color saturation and brightness values.

The control displays a two-dimensional gradient of color values for a given hue, where the vertical gradient represents brightness, and the horizontal gradient represents saturation.
A gripper can be dragged to change the selected color.
Setting the Hue
This picker shows the saturation and brightness cross-section for a particular hue. Therefore it is important to set the Hue property appropriately. 0 is red, 120 is green, and 240 is blue. The hue may be set to any value between 0 and 360.
Sample XAML
This control can be placed within any other XAML container control, such as a Page or Panel with this sort of XAML:
<editors:SaturationBrightnessPicker Hue="120" Saturation="{Binding Path=YourSVMProperty, Mode=TwoWay}"
Brightness="{Binding Path=YourBVMProperty, Mode=TwoWay}" />