I'm trying to use libPd, the wrapper for PureData. But the documentation is poor and I'm not very into C++ Do you know how I can simply send a floating value to a Pd patch?
Do I need to install libPd or I can just include the files?
if you want to send a value to a running instance of Pd (the standalone application), you could do so via Pd's networking facilities.
e.g.
[netreceive 65432 1]
|
[route value]
|
[print]
will receive data sent from the cmdline via:
echo "value 1.234567;" | pdsend 65432 localhost udp
you can also send multiple values at once, e.g.
echo "value 1.234567 3.141592;" | pdsend 65432 localhost udp
if you find pdsend to slow for your purposes (e.g. if you launch the executable for each message you want to send you have a considerable overhead!), you could construct the message directly in your application and use an ordinary UDP-socket to send FUDI-messages to Pd.
FUDI-messages really are simple text strings, with atoms separated by whitespace and a terminating semicolon, e.g.
accelerator 1.23 3.14 2.97; button 1;
you might also considering using OSC, but for this you will need some externals (OSC by mrpeach; net by mrpeach (or iemnet)) on the Pd side.
as for performance, i've been using the latter with complex tracking data (hundreds of values per frame at 125fps) and for streaming multichannel audio, so i don't think this is a problem.
if you are already using libPd and only want to communicate from the host-application, use Adam's solution (but your question is a bit vague about that, so i'm including this answer just in case)