[LAD] LV2::Synth from one note to another

Raine M. Ekman raine at iki.fi
Wed Oct 8 12:36:14 UTC 2014

> Phil CM <philcm at gnu.org> wrote:
>> Now the only think that is left is a portamento function, to go from
>> one note to another (/exactly/ like so-404
>> <http://d00m.org/%7Esomeone/so404/> does).

>> Does anyone know the algorithm to implement that? That would really
>> help me.

Quoting Philipp Überbacher <murks at tuxfamily.org>:
> I have never done this but I suggest to look at the calf monosynth
> code. AFAIR it has a couple of different ways to handle
> successive/overlapping notes.
> Another synth that comes to mind and has portamento is phasex.

Well, if it has to be exactly the same, I'd suggest digging in the  
so-404 code and not in those other synths. Looks like it adjusts  
frequency at samplerate/100, calculating:
freq = ((portamento/127.0)*0.9)*freq + (1.0-((portamento/127.0)*0.9))*tfreq;

I guess tfreq is the target frequency of the note being portamented towards.

raine at iki.fi

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