[LAD] "enhanced event port" LV2 extension proposal

Krzysztof Foltman wdev at foltman.com
Thu Nov 29 13:23:49 UTC 2007

Lars Luthman wrote:

> OK, maybe. It's trivial to add a "safe" RDF indicator in a separate
> extension and just assume that an event type is not safe if it doesn't
> have it.

Fair enough.

> For that case I think it would be cleaner if the host just splits the
> processing period in smaller parts if it needs to fit in more events per
> time unit. The plugin doesn't need to worry about it.

Yes. But that makes it impossible to use a fixed size buffer. If we
already have a fixed size buffer extension, why break it this way?

(note: I'm not saying that fixed size buffers are always a nice thing,
but let's think about it before it's too late)

> And mine is wrong too. Embarassing. This works:
>   index += (events[index].size + 23) / 16;

Yes, that's the correct one. Mine would only be correct if 'size' meant
size of the whole event including 8-byte header, not the size of the

> all. So I guess the cleanest way would be to not list the uri-map thing
> as a separate lv2:Feature in the RDF data but require that a host that
> handles events passes that LV2_Feature to the plugin's instantiate
> callback if it is going to connect a non-NULL buffer to any event ports.

Why not use lv2:optionalFeature?


More information about the Linux-audio-dev mailing list