[LAD] minimal LV2

[Gabriel M. Beddingfield]

Hi Fons,

On Sun, 13 Jun 2010, fons at kokkinizita.net wrote:

> So I have a simple question:
>
> What is the absolute minimum required to define an LV2
> plugin (in other words, which files, and what do they
> need to contain) assuming the following:

Minimum to define an LV2 plugin is here:

     http://lv2plug.in/docs/index.php?title=Writing_Plugins
     http://lv2plug.in/plugins/Amp-example.lv2

> - The plugin requires one 'extension'.
>
> - This extension defines everything except whatever is
>  required to enable a host to discover the existence
>  of the plugin on a system.
>
> - In other words the extension defines how the host is
>  supposed to instantiate and call the plugin, the way
>  ports and parameter are described, etc. etc.

When you start adding extension requirements, this 
documentation is currently buried in the bowls of lv2.ttl 
(http://lv2plug.in/spec/lv2.ttl).  You declare it in your 
plugin's .ttl file.  Here's an example from zynadd, with the 
lv2:optionalFeature and lv2:requiredFeature lines:

==========================================================
<http://home.gna.org/zyn/zynadd/1>
   a lv2:Plugin;
   doap:maintainer [
     foaf:name "Nedko Arnaudov";
     foaf:homepage <http://nedko.arnaudov.name/>;
     foaf:mbox <mailto:nedko at arnaudov.name>;
   ];
   doap:name "zynadd";
   doap:homepage <http://home.gna.org/zyn/>;
   doap:license <http://usefulinc.com/doap/licenses/gpl>;
   lv2:optionalFeature <http://home.gna.org/lv2dynparam/v1>;
   lv2:requiredFeature <http://home.gna.org/lv2dynparam/rtmempool/v1>;

   lv2:port [
....
=============================================================

-gabriel