Apple Logic Pro 9 - Manual (Page 743)

Using the Map
128 vertical bars reflect the full MIDI value range (from 0 to 127), and provide a visual
overview of the transformation.
Essentially, each bar represents a particular MIDI value, which can be mapped to a different
value. The type of event, and operations, are determined in the Selection Conditions and
Operations areas.
For example:
• Each of the bars could represent a MIDI note number (from 0 to 127) value.
• By default, there is a 1:1 relationship for each bar, where value 1 = value 1, value 15 =
value 15, and so on, throughout the 128 bars. Applying this to MIDI note numbers,
bar 60 = C3 (middle C), bar 61 would represent C#3, bar 62 = D3, and so on.
The default and mapped values are shown in the two fields to the lower left of the map
area.
• You can alter these values directly in the fields, or by dragging any of the bars vertically.
As you do so (using either method), the corresponding field or bar is updated.
• If you alter the bar 60 (middle C) value to show 72 in the “mapped to” field, this value
is remapped accordingly when the transform operation is applied.
This results in all MIDI note number 60 messages being transformed into MIDI note
number 72 messages (effectively transposing all C3 notes to C4).
Some Points to Note About the Map
The map is only visible when chosen in one of the Operations pop-up menus. Appropriate
selection conditions must also be set, or the map does not appear.
The map is universal, which means that it remaps one MIDI value to another.
It does not know what type of MIDI data is sent to it. It is only concerned with the value
of the data.
This means that one map can be used to simultaneously alter the pitch, velocity, and
length values of incoming note events, for example.
743 Chapter 26 Editing MIDI Events in the Transform Window