Ksp reference Manual

8.15. set_event_mark()
set_event_mark(,mark>)
Assign the specified event to a specific event
group

The ID number of the event to be grouped

Here you can enter one of 28 marks from 
$MARK_1
to 
$MARK_28
which
is assigned to the event. You can also assign more than one mark to a
single event, either by typing the command or by using the operator +.
Remarks
When dealing with commands that deal with event IDs, you can group events by using
by_marks()
instead of the individual ID, as the program needs to know that you
want to address marks and not IDs.
Examples
on init
declare $new_id
end on
on note
set_event_mark($EVENT_ID,$MARK_1) 
$new_id := play_note($EVENT_NOTE + 12,120,0,-1) 
set_event_mark($new_id,$MARK_1 + $MARK_2)
change_pan(by_marks($MARK_1),-1000,1) {both notes panned to left}
change_pan(by_marks($MARK_2), 2000,1) {new note panned to right}
end on
The played note belongs to group 1, the harmonized belongs to group 1 and group 2
See Also 
by_marks()
delete_event_mark()
$EVENT_ID
$ALL_EVENTS
$MARK_1 … $MARK_28
Event Commands
65
KSP Reference Manual

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