someone asked for it on kvr-audio.
I use it in an unreleased additive synth.
There's no oversampling needed in my case since I feed it with a pure sinusoid and I
control the order to not have frequencies above Fs/2. Otherwise you should oversample by
the order you'll use in the function or bandlimit the signal before the waveshaper. unless
you really want that aliasing effect... :)
I hope the code is self-explaining, otherwise there's plenty of sites explaining chebyshev
polynoms and their applications.