Radial Colors Effect Plugin     What's this? This effect is an (r)evolution of the Radial.cs provided with the CodeLab. I took this example to test more the new possibilities offered by the version 3.20 of Paint.net, regarding 'user interface'.   I've also made the Rainbow Twist in the same way http://forums.getpaint.net/index.php?showtopic=7182     How does it works? The effect uses the predefined formulas based on sinusoid curves