[Sc-devel] [documentation] Shaper

[Stephan Wittwer <s@xxxxxxxxxx>]

Hi, the following from Shaper help file  is wrong:

/*
Wavetable format is a special representation which includes an extra  
number between each sample containing the difference between two  
adjacent samples, to make linear interpolation faster.

Signal: [a0, a1, a2...]
Wavetable: [a0, a1-a0, a1, a2-a1, a2, a3-a2...]

If your buffer doesn't have the deltas between adjacent samples, the  
calculations are wrong and you get distortion.
*/


Right would be:

Signal: [a0, a1, a2...]

Wavetable: [
	2 * a0 - a1 , a1 - a0,
	2 * a1 - a2, a2 - a1,
	2 * a2 - a3, a3 - a2
	...
]


Also, as pointed out by JMC here:
<http://www.create.ucsb.edu/pipermail/sc-users/2007-February/ 
031727.html>

Signal:asWavetable (from SC2) is not suited so well for waveshaping  
tables. It is for cycling, wrapping waves.


Regards,
Stephan