LilyPond Beginnershandleiding

Hoofdstuk 4: Tweaking output 90
\override is the most common command used in tweaking, and most of the rest of this
chapter will be directed to presenting examples of how it is used. Here is a simple example to
change the color of the note head:
c4 d
\override NoteHead.color = #red
e4 f |
\override NoteHead.color = #green
g4 a b c |
The \revert command
Once overridden, the property retains its new value until it is overridden again or a \revert
command is encountered. The \revert command has the following syntax and causes the value
of the property to revert to its original default value; note, not its previous value if several
\override commands have been issued.
\revert Context.LayoutObject.layout-property
Again, just like Context in the \override command, Context is often not needed. It will be
omitted in many of the following examples. Here we revert the color of the note head to the
default value for the final two notes:
c4 d
\override NoteHead.color = #red
e4 f |
\override NoteHead.color = #green
g4 a
\revert NoteHead.color
b4 c |
The \once prefix
Both the \override and the \set commands may be prefixed by \once. This causes the following
\override or \set command to be effective only during the current musical moment before the
property reverts back to its previous value (this can be different from the default if another
\override is still in effect). Using the same example, we can change the color of a single note
like this:
c4 d
\override NoteHead.color = #red
e4 f |
\once \override NoteHead.color = #green
g4 a
\revert NoteHead.color
b c |