This extension defines a structure type, LV2_Time_Position, which describes a tempo and position along a timeline. This can be used as an event payload by the host to notify plugins about the current tempo and position.
Type for an LV2_Time_Position struct. This can be mapped to an integer and used as the type field of an event to indicate that the event payload is an LV2_Time_Positon struct. Plugins SHOULD indicate that a port supports time information using the ev:supports predicate, e.g.: <plugin> lv2:port [ a lv2:InputPort , ev:EventPort ; lv2:name "control" ; lv2:index 0 ; ev:supportsEvent time:Position ] .