[Rosegarden-devel] Extension for SegmentSplitByPitchCommand

[Tom Breton (Tehom) <tehom@pa...>]

I extended SegmentSplitByPitchCommand with 3 other ways of splitting by
pitch:

 * Split off the lowest tone in a chord
 * Split off the highest tone in a chord
 * Split chord at an arbitrary place (eg, always split off the two
   lowest tones).  It uses the user's split pitch and the first chord
   to determine where to split.

It's intended for instruments like guitar that play chords slightly
arpeggiated.  A typical use case would be:

 * Start with a segment of mostly chords
 * Split it segment by chord tone
 * Repeat until each chord tone has its own segment (eg, if it's all
   triads, split by lowest tone twice, giving three segments, one
   having the highest note of every chord, one the middle note, one
   lowest)
 * Delay the segments different amounts. (eg delay the highest line 20
   ms and the middle line 10 ms)

I left the ranging functionality untouched, but rearranged the interface
slightly.  getSplitPitchAt handles all the splitting strategies while
getNewRangingSplitPitch contains essentially the old ranging code.

It adds 4 user-visible texts and changes a checkbox to a combobox.

	Tom Breton (Tehom)

Re: [Rosegarden-devel] Extension for SegmentSplitByPitchCommand

[D. Michael McIntyre <michael.mcintyre@ro...>]

On Monday, June 04, 2012, Tom Breton (Tehom) wrote:

> I extended SegmentSplitByPitchCommand with 3 other ways of splitting by
> pitch:

Interesting...

I don't have time to play with this right now, but that seems like it has a 
lot of potential to be useful.  My first thought is that this is probably the 
ticket needed for getting sensible notation out of an imported MIDI part that 
has guitar parts that feature ringing bass notes.

Another situation along the same lines...  I always meant to get around to 
writing a split command that would break parts up so that each one only had a 
single note at any given time, with no chords.  The idea is to take a part 
written for a single polyphonic instrument, like a piano, and split it out so 
that some collection of individual monophonic instruments could cover all the 
notes in their respective parts.  You had one piano playing major triads, now 
you have three trumpets playing single lines that converge to form major 
triads.  Being able to "reverse engineer" a piano reduction into separate 
individual parts would be wicked useful, but I just never did quite tinker 
with the idea far enough to get anywhere close to implementing it.
-- 
D. Michael McIntyre