[LV2] port-groups

[David Robillard]

On Sun, 2016-03-27 at 17:46 -0700, Alex Norman wrote:
> I'm working on a libpd lv2 wrapper and I'm curious about getting port-group
> support working.
> 
> I first saw this documentation:
> http://ll-plugins.nongnu.org/lv2/ext/portgroups/
> 
> but it seems to conflict somewhat with this:
> http://lv2plug.in/ns/ext/port-groups/
> 
> in the lv2plug.in docs I see no mention of pg:membership, pg:rightChannel,
> pg:leftChannel etc.
> 
> I'm wondering if I'm missing something or if the ll-plugins docs are just out of
> date?

These are different extensions.  The ll one is very old, deprecated, and
AFAIK not really used by anything these days except a few extremely
crusty old things lurking around untouched in repositories for years.

Ignore it and use the lv2plug.in extension.

> Finally, is there a host that _really_ illuminates the usefulness of port
> groups? They seem like they could be useful but I'm not exactly sure if/when a
> host is using them so I'm not exactly sure how to test that my annotation is
> correct.

jalv.gtk groups controls and uses group labels to display things more
nicely in the generic UI.  For example, try:

jalv.gtk -g http://code.google.com/p/amsynth/amsynth
jalv.gtk http://drobilla.net/plugins/mda/JX10

-- 
dr