lilypond-0.1.62

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+=head1 NAME
+
+Octaves --  how to do pitches
+
+=head1 DESCRIPTION
+
+The LilyPond input language, Mudela (help, silly name), should be easy
+to read and write.  In my experience Mudela is already quite convenient 
+for entering music.  Every time i've entered a substantial piece of music, 
+however, i found that i made quite a few mistakes.  The MIDI output helps 
+a lot with locating and correcting the errors.  There's one type of error 
+that seems to be frequent, stubborn and hard to catch, and that's the
+octavation error.  The relative octave feature is an attempt to make
+Mudela a bit easier to write.  In addition, this featuer makes it harder 
+to make octavation mistakes, yet if you made one, its a lot simpler to find 
+and correct.
+
+Here's how it works.  
+
+=over 5
+
+=item * 
+forget the old "\octave c';" command
+
+=item * 
+forget the old octave boundaries with octaves c .. c'
+
+=back
+
+You start the relative octave mode (for now) with the command
+
+    \octave relative;
+
+From then on, the pitch of a note will be the closest to the last one,
+assuming that large intervals are a lot more rare than small ones. 
+Thus, you can enter a scale without using octavation quotes:
+
+    c d e f g a b c
+
+the last c being an octave higher than the first.  If you have to
+enter an interval that is greater than a quart, you must specify
+whether the pitch goes up, using post-quotes:
+
+    c c' % octave up
+    c g' % quart up 
+
+or down, using pre-quotes:
+
+    c 'c % octave down
+    c 'f % quart down
+
+Although it is not necesary, and thus redundant, information to specify
+the direction of smaller intervals, you are allowed to do so:
+
+    c d  % second up
+    c d' % second up
+
+    c a  % third down
+    c 'a % third down
+
+
+=head1 CONVERTING
+
+To convert a piece of music from the old absolute-octave notation to
+relative octaves, lilypond provides the B<-f, --find-quarters> feature
+to locate all big intervals in your music (sorry, fully automated convert 
+is too complex).
+
+You'll do something like this:
+
+    lilypond -f los-toros-oboe 2>&1 | tee intervals
+    ...
+    los-toros-oboe.ly: 59: warning: Interval greater than quart, relative: d':
+        [)g8  r d
+                 '] r |
+    los-toros-oboe.ly: 100: warning: Interval bigger than quart, relative: d':
+       [d8 d
+             '] [es'8.-> c'16] |
+    ...
+
+Then you load a copy of the original mudela file in your favourite editor, 
+and let it parse the 'error file' F<intervals>.  First you remove all 
+octavation quotes.  Then, jumping from warning to warning, you enter quotes 
+as suggested by LilyPond.
+
+=head1 EXAMPLE
+
+See F<mutopia/ltor.ly>.