From 70d225871dbb58d770150abcc4b9e7907fabb19d Mon Sep 17 00:00:00 2001 From: David Robillard Date: Fri, 23 Mar 2012 22:30:30 +0000 Subject: Add lv2:Parameter and better document the concept. --- lv2/lv2plug.in/ns/lv2core/lv2core.ttl | 50 ++++++++++++++++++++++++----------- 1 file changed, 35 insertions(+), 15 deletions(-) (limited to 'lv2') diff --git a/lv2/lv2plug.in/ns/lv2core/lv2core.ttl b/lv2/lv2plug.in/ns/lv2core/lv2core.ttl index 57f4fc8..7d0e729 100644 --- a/lv2/lv2plug.in/ns/lv2core/lv2core.ttl +++ b/lv2/lv2plug.in/ns/lv2core/lv2core.ttl @@ -449,32 +449,52 @@ port identification. The plugin author may change the values of this property without changing the Plugin URI. """ . +lv2:Parameter + a rdfs:Class ; + rdfs:subClassOf rdf:Property ; + lv2:documentation """ +

A parameter of a plugin. A parameter is simply a recognized +property, identified by URI. Parameters are abstract in the sense that they +may be controlled by several methods. The simplest is with an +lv2:ControlPort, which can be associated with a parameter using +lv2:isParameter. Other methods, such as setting dynamic parameters via +messages, are possible but not defined in this specification. The concept of a +parameter is deliberately separate from any particular code mechanism, so that +a parameter can be defined once and used in several contexts.

+ +

Parameters are meaningful controls which allow hosts to act +intelligently. For example, if a plugin has a foo:volume parameter, and the +host understands it, the host knows how to automatically control the volume of +that plugin.

+ +

Any existing property can be used as a parameter, an LV2 specific definition +is not required.

+""" . + lv2:hasParameter a rdf:Property , owl:ObjectProperty ; - rdfs:domain lv2:Resource ; - rdfs:range rdf:Property ; + rdfs:range lv2:Parameter ; rdfs:label "has parameter" ; lv2:documentation """ -

Indicates that a plugin or other resource has a certain parameter. A -parameter is simply a recognized property, i.e. a URI predicate and any type of -object. Parameters may be associated with a control port or controlled using -another mechanism. Parameter values may be part of an instance's state.

+

Indicates that a specific parameter is supported. This predicate is to +advertise that a plugin supports a parameter in some way other than a port +value, such as a message interface. It is not necessary use for control port +parameters, simply use lv2:isParameter on the port for that.

-

Any property URI can be used as a parameter, no LV2 specific definition is -required. Existing vocabularies SHOULD be used whenever possible.

+

This property may be used to indicate any resource has a parameter, it is +not restricted to plugins.

""" . lv2:isParameter a rdf:Property , owl:ObjectProperty ; rdfs:domain lv2:Port ; - rdfs:range rdf:Property ; - rdfs:label "relation" ; + rdfs:range lv2:Parameter ; + rdfs:label "is parameter" ; lv2:documentation """

Indicates that a port contains the value of a plugin parameter.

-

For example, if a port lv2:isParameter foo:volume, then the value of that -port represents the foo:volume of the plugin instance. Associating a port with -a well-defined parameter gives the port's value meaning. This allows it to be -handled specially by the host and integrate with other property-based -mechanisms (e.g. messages or plugin state).

+

For example, if a port lv2:isParameter foo:gain, then the value of that port +represents the foo:gain of the plugin instance. Associating a port with a +well-defined parameter gives the port's value meaning, which allows the host +to use the port more intelligently.

For a given parameter, plugins SHOULD have at most one port per direction (lv2:InputPort or lv2:OutputPort).

""" . -- cgit v1.2.1