[linux-audio-dev] LV2 plugin porting experience

I thought it might be of interest to other plugin developers to learn what
my experiences were of porting my LADSPA plugins to the LV2 draft.

As some of you may know the primary source for my plugins is a wierd XML
format, so porting that was fiddly, but didn't involve much manual effort,
"just" coding a handful of XSLT sheets.

However I ported a couple by hand to get a feel for it, and basically it
comes down to deleting the constants and runAdding method from the ladspa
.c file, sedding some struct names and replacing occurances of LADSPA_Data
with float (except the last argument to connectPort, which is a void *).
It may be possible to do it automatically with a cpp/m4 hack, or a perl
script or something, but I doubt its worth the effort.

Writing the turtle is a little more involved, but I'm sure some
enterprising person can write a program to generate .ttl from existing
LADSPA .so's, then it will be a case of adding any additional data you
want to express by hand.

Writing the Makefile was pretty tricky, as the plugin data and code all
ends up in a plugin directory, but it wasn't too bad once I figured out
how best to layout the source. I decided not to use automake/autoonf/
ibtool as I felt it caused more probems than it solved with LADSPA. The
Makefile would have been less critical if I didn't have quite so many
plugins; I didn't want to recurse into every plugin directory, which is
the obvious thing to do.

- Steve
Received on Tue Jun 20 12:15:03 2006