[PD] Messages in an external

IOhannes m zmoelnig zmoelnig at iem.at
Thu Nov 3 18:24:57 CET 2005

Piotr Majdak wrote:
> Hi!
> IOhannes m zmoelnig wrote:

> Do I understand it correctly:
> - calling outlet_float(), a depth-first handling of all objects attached 
> to this outlet is triggered?


> If yes, what must be guarrantied to avoid clicks:
> - the handling of _this_ message must be completed within one sample 
> block or
> - the handling of _all_ messages of _this_ external must be completed 
> within one sample block or
> - tha handling of _all_ messages of _all_ objects in pd must be 
> completed within one sample block?
> If you tell me which of these statements is correct, I'm able to 
> estimate the maximal number of messages for my machine.

the 3rd one is the _most_ correct: in addition, the audio processing 
needs to be done within the one sample block too :-(

however, pd's audio processing is buffered, so it's ok if it happens now 
and then, if the messages cannot be completed within one sample block.
message handling somewhat floats with respect to the real time.
this is basically what the "audiobuf" is for.

and of course, if your messages keep needing more time to evaluate than 
one audioblock, your patch is unusable. (with "keep" i mean, that e.g. 
each and every audioblock you need more time than you have)
luckily this is rather seldom.

> What is the difference between the pd-devel and the 0.39.1? Is there a 

everything :-)

> readme/howto I could read before trying the pd-devel version?

the only readme/howto (i know) is pd-dev.


More information about the Pd-list mailing list