[PD-dev] is "dsp_addv" ready for multichannel?

[Christof Ressi]

Hi,

the problem is here:

https://github.com/porres/pd-else/blob/2d53dfa7bd02b1fd102dbad7a2f9799df0a32e37/Code_source/Compiled/signal/xgate.mc~.c#L67-L68

signal_setmultiout() changes the signal pointer, so you must call it 
/before /assigning the signal pointer to the arg vector for dsp_addv()! 
Just swap these two lines and you should be good.

---

Some further notes:

1. I think you don't need x_outs at all when using dsp_addv(). The 
following lines are completely redundant:

https://github.com/porres/pd-else/blob/2d53dfa7bd02b1fd102dbad7a2f9799df0a32e37/Code_source/Compiled/signal/xgate~.c#L41-L42

2. Never ever send a Pd message directly from a perform routine! Always 
use a clock!

https://github.com/porres/pd-else/blob/2d53dfa7bd02b1fd102dbad7a2f9799df0a32e37/Code_source/Compiled/signal/xgate~.c#L50-L55

3. Why calloc/free instead of getbytes/freebytes? (In this particular 
case, it would also be safe to just use alloca())

https://github.com/porres/pd-else/blob/2d53dfa7bd02b1fd102dbad7a2f9799df0a32e37/Code_source/Compiled/signal/xgate~.c#L67-L72

Christof

On 09.08.2023 15:41, Alexandre Torres Porres wrote:
> Ok, I tried building my new object and it crashes Pd as I expected.
>
> Here's the original [xgate~] code, and I'm highlighting a specific 
> line in it because the same thing in the "mc" version is what's 
> crashing Pd.
>
> https://github.com/porres/pd-else/blob/master/Code_source/Compiled/signal/xgate~.c#L57
>
> and here's the [xgate.mc <http://xgate.mc>~] code, which is exactly 
> the same thing 
> https://github.com/porres/pd-else/blob/master/Code_source/Compiled/signal/xgate.mc~.c#L52
>
> But now it seems "*x->x_outs[n]++" doesn't work. The only difference 
> is that the outlets are now multichannel but Pd crashes even if the 
> input is a single channel.
>
> Not sure yet if it is something about "dsp_addv" not working for 
> multichannels. I also suspect I need to adapt the code a bit in this 
> case for some unknown reason to me.
>
> please help
>
> thanks
>
> Em qua., 9 de ago. de 2023 às 00:57, Alexandre Torres Porres 
> <porres at gmail.com> escreveu:
>
>     Hi, I am having a hard time using "dsp_addv" with a
>     multichannel external.
>
>     I am trying to make a multichannel version of [else/xgate~], which
>     routes a signal to different outputs with crossfading. It
>     originally uses "dsp_addv" so it can have a DSP routine with a
>     variable number of outlets, which is specified by an argument.
>
>     So now I want these outlets to output multichannel signals and I
>     have run into trouble before trying to use "dsp_addv" with
>     multichannel signals. I was able to avoid it before but now I
>     can't and I wanna be sure before I try it.
>
>     thanks
>
>
>
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