[LAD] random curiosity

[Folderol]

On Wed, 27 Jan 2010 06:54:00 -0600 (CST)
"Gabriel M. Beddingfield" <gabrbedd at gmail.com> wrote:

> 
> 
> On Wed, 27 Jan 2010, cal wrote:
> 
> > Jens M Andreasen wrote:
> >> [ ... ]
> >> I am surprised that nobody so far has suggested using the key and
> >> velocity as a "salt" to differentiate a single stream of randomness?
> >
> > If you don't mind, how would one go about "salting" it?
> 
> One way that comes to mind:
> 
>      unsigned short int note, velocity;
>      // ...
> 
>      unsigned int salt = ((velocity & 0x7F)<<7) | (note & 0x7F);
>      struct random_data seed;
> 
>      srandom_r(salt, &seed);
> 
> Thus, if you repeat the note with identical velocity... 
> you'll always get the same random-number sequence.
> 
> -gabriel


Hmmm,
Getting identical note and velocity is going to be quite common on
sequencer generated stuff, so I would have thought this was rather
undesirable. While there have been odd occasions when I've wished I
could reliably re-create a pseudo random sequence, in general I would
not want repeated identically created notes to sound exactly the same.

-- 
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.