On Sunday 03 August 2008, you wrote:
> And yes, now that I look again, LilyPond is clearly showing D major for
> everything after this missing key signature too.
That's where your C-naturals were coming from. LilyPond thought the key was
still D, and it spelled the pitches according to the key.
Rosegarden's internals use a MIDI pitch with key and explicit accidental
properties to decide how to draw a note. This pitch resolved to C in the
then-active key of C major.
LilyPond requires everything be spelled out explicitly. If you're writing in
the key of D, you have to writes your Fs and Cs sharp explicitly every time,
and then LilyPond decides not to draw accidentals for these pitches because
they are in key. These C-in-C-major pitches were exported as "c" instead
of "cis" because that was correct under the circumstances from Rosegarden's
LilyPond had the wrong idea of the active key signature for some reason we
won't even try to assign any blame to at this juncture, and therefore
interpreted the "c" (not "cis") in active key of D major as C-natural.
If nothing else, Chris, you have managed to come up with a good puzzle for me,
and I do appreciate the variety!
Now go put your key signature in the right place, and carry on!
D. Michael McIntyre