Astor Plot Color Saturation

Im trying to create a type of Astor Plot in order to show the wind direction, intensity, and frequency of direction in a circular manner.  I can sow it using a column chart where the direction is the x-axis, the average speed the y-axis, and the color saturation the frequency of that direction.  The problem with doing this in an Astor Plot is that the sweep angle for each direction gets distorted when I add a thrid value to the mix.

It would be really nice have the color saturation attribute on this visualization.