Optimize phase unwrapping

[mtmccrea]

The issue of interpolating across the 0/2pi and -pi/+pi boundaries is a recurring issue, currently "handled" by the fact that FOA transforms run at audio rate only. The current implementation in the UGens is "UNWRAPANGLE" and can be optimized.

Here's a lead to do that: https://gist.github.com/mtmccrea/8f891a8f15f24b11f5374eeb6f4f26f3

The problem still persists when the control value sent in runs at K-rate at some point in the chain (and so is interpolated before getting to the transform UGen). This potentially calls for a new type of interpolation from CALCSLOPE in sc UGens which can deal with interpolating non-contiguous values (essentially unwrap the phase, then mod it back into range).

[mtmccrea]

bread crumb: see moddif operator

[joslloand]

QUESTION: Is there a similar issue with the HOA implementation?