Apple Logic Pro 8 - Manual (Page 900)

900 Chapter 39 Working in the Environment
3 Cable the output of the transformer object into this newly created instrument (which,
in essence, is simply acting as a MIDI output port.
Configuring a Transformer Object
Double-clicking a transformer icon opens the Transformer window, where you can set
the conditions and operations.
Setting the Operation Mode
Use the pop-up menu at the top of the Transformer window, to define how a
transformer handeles MIDI events. You can choose between the operation modes
outlined below.
Apply operation and let non-matching events pass thru
MIDI events that match the condition are processed. MIDI events that don’t conform to
the condition are passed thru.
Apply operation and filter non-matching events
MIDI events that conform to the condition are processed. MIDI events which do not
conform to the condition are not passed through.
Filter matching events
All MIDI events which match the condition are filtered out. MIDI events that don’t
conform to the condition are passed through.