On 6/5/10 8:56 PM, Kim Cascone wrote:
- I remember Derek mentioning a 'workaround' in the archives but was
unable to find the solution - (was it recompiling the plugin~ object?) can someone point me to the workaround?
I've pasted my reply from the thread "easy effects", and I also started a page on plugin~/LADSPA in the FLOSS Manual (*very* rough, needs a lot of expansion!):
http://en.flossmanuals.net/bin/view/PureData/UsingLADSPAplugins
[plugin~] can be tricky or just a plain pain the wazoo to use simply because it can crash when given the wrong creation arguments, such as the name of a plugin that doesn't exist on your computer. Of course, a help patch which crashed on anybody's computer should be a high priority to fix, but maybe not everybody around here seems to agree with that ;-) I posted about this problem in 2005 and still it hasn't really been dealt with.
[plugin~] requires the path to your LADSPA directory to be set as the LADSPA_PATH in the environment. Look up "setting environmental variables" plus either "bash" or "shell" on Google to see how this is done if you don't know how.
If you use the terminal command "listplugins", you should see a list of the LADSPA plugins on your system. You must use the exact name listed there, for example, if "listplugins" gives you:
/usr/local/lib/ladspa/noise.so: White Noise Source (1050/noise_white)
then you would use [plugin~ noise_white]. (Somebody correct me if this is wrong, I am not on a Linux system where I can check this for the next several days...)
Then, you need to send the proper control parameter number, and NOT the control parameter name. For example, if sending the message "info" to the plugin lists the following to your Pd window via [print]:
Loaded from library "/usr/lib/ladspa/mvclpf24.so". Control input(s): #1 "Input gain (dB)" #2 "Frequency" #3 "Exp FM gain" #4 "Resonance" #5 "Resonance gain" #6 "Filter poles" #7 "Output gain (dB)" Control output(s): Audio input(s): #1 "Input" #2 "Frequency" #3 "Exp FM" #4 "Resonance" Audio output(s): #1 "Output"
Then you would have to make a message "1 $1" to send a variable to control the input gain from a number box or slider.
More info on LADSPAs in general:
http://linuxdevcenter.com/pub/a/linux/2001/02/02/ladspa.html
If somebody would like to make a chapter on this in the Pd FLOSS Manual, I would jump for joy. I just haven't had the time to do it myself. Feel free to copy paste from this email and make some screenshots! ;-)
You can also search for "plugin~" in the list archives and find much discussion on this. The two threads I started were called "plugin~ ladspa" and "setting plugin~ control inputs" in about 2005, when I was trying to figure this all out.
Best! Derek