[PD] Help with a patch

[Frank Barknecht]

Hallo,
David Powers hat gesagt: // David Powers wrote:

> I am making a simple patch to automatically morph between parameters 
> every so often. One idea for this is, if I end up VJing at the 6 am 
> afterparty and I am too drunk, I can have it morph things for me and I 
> can take a break. :) Well, I'm not sure if that is a joke, or if it's true.
> 
> Anyway, I know I'm doing something stupid with this patch, that causes 
> it not to work right. The first time I run it, I hit bang, and it 
> outputs twice to the print, instead of once - there is some kind of loop 
> that I don't want. 

The [s top] at the bottom will be read in again at the [r top] at  the
top and thus it will bang the [pack] twice at the first start.

Why does it do so? Because you didn't use [trigger] and have "fanned"
connections in your patch at a crucial place: the outlet of [pd
get_new_target]. Always use [t] where order might matter. Always. 

So, the outlet of [pd g_n_t] goes to both the pack and the select. But
which one will get it first? It's undefined without trigger. In your
patch currently the [pack] gets it first, then the [select]. So at the
first random number, lets call it A, [pack] will start a ramp from 0
to A, and [select] will first look for a 0, then for A. It will get
the zero immediatly from the pack->line, because [line] starts at 0,
so "change->sel->s top" will bang and reinitiate a new random number,
lets call it B. B will get send to both [pack] and [select] again. In
your patch, again the [pack] will get it first, then the [select],
however actually the order is undefined as you didn't use [trigger]. 

So while [line] still is trying to reach A, [select] now is waiting
for B which it might never see, if B is not in the range 0,...,A.

So to fix your patch, the old saying stays true: Pd stands for "Pull
da trigger!"

Btw: You could also replace the  [== 0][change][sel 1] construct with a
simple [del] whose delaytime you set from the "[random 3000] + 500".

Ciao
-- 
 Frank Barknecht                 _ ______footils.org_ __goto10.org__