Vertical stretching of groups

[Reinhold Kainhofer]

Without much success, I'm currently trying to create a proper vertical page 
layout for one of my full scores with one system per page. I still have some 
very serious issues, some which make the scores unusable for a conductor or 
piano accompaniment:

-) How can I define globally that direct child staves/groups of 
SimulaneousMusic can be spaced any amount, immediate child staves/groups of 
StaffGroup are stretched a little less, the staves of a ChoirStaff are 
stretched only a little, and the staves of a PianoStaff are hardly stretched 
at all? 
The max-stretch seems to do this, but unfortunately it seems to not look at 
staff distances. For example, between two child staves of a choir staff, 
there are already the lyrics, some dynamics etc., so when stretching, there 
should not be any space added until the other staves are spaced as much as 
the child staves of ChoirStaff already are. Currently, the staves of a choir 
staff are spaced a lot more then e.g. the two violins or as the space between 
the brass and the string group (which should be the largest spacing of the 
score!!!!). 
E.g. Gardner Read clearly describes in his book that the instrumental groups 
should have less spacing for their staves than the spacing to between the 
groups. I've not been able to achieve this in lilypond yet.

-) How can I decrease the distance of a FiguredBass to the staff it is 
assigned to (i.e. it's define inside a staff, but appears wayyyy below that 
staff instead of immediately below the staff). I have already the settings 
    \override VerticalAxisGroup #'keep-fixed-while-stretching = ##t
    \override VerticalAxisGroup #'minimum-Y-extent  = #'(0 . 1)
    \override VerticalAxisGroup #'padding = #0
for the FiguredBass context, but there is still some space above the Figured 
basse.

-) If in a full score there is enough space for two systems on a page, the two 
systems are not stretched at all, and instead the remaining empty is simply 
inserted in the middle of the page between the two systems (leaving ~3-5 cm 
of empty space), 
Similarly, on the first page, the system is not stretched at all, but instead 
the space is inserted between the title and the score. If I limit the spacing 
between systems using
   page-limit-inter-system-space = ##t
   page-limit-inter-system-space-factor = 1.1
then the system is still not stretched more, but the space is inserted at the 
bottom, which is even worse. Additionally, in this case, the preface is also 
not stretched, which is fatal for my scores. So, is there a way to enable 
conventional stretching (of markups) for the preface of my score and then 
change the behavior to use page-limit-inter-system-space-factor or something 
similar to force lilypond not to leave too much space between the systems and 
stretch the systems instead? (BTW, stretching IS enabled with a very large 
max-stretch, it only doesn't work in the way that I would need it...)

Thanks a lot for your help,
Reinhold

PS: If you can't imagine what I'm talking about, here are some example 
outputs:

-) A4 score, the first page has large spacing after the title and before the 
score, the other pages have a large irregular space at the bottom, the 
systems are not stretched properly (although stretching is turned on):
http://www.fam.tuwien.ac.at/~reinhold/temp/Pembaur_VierteLateinischeMesse_LongScore_normal.pdf
All systems should end at the very bottom of the page and not leave any empty 
space!
Also note how the vocal staves are spaced way more than any of the other 
staves, which is simply bad layout according to the experts :-(((

-) The same score, paper 10cm higher, to show that stretching is actually 
enabled. The systems are stretched more, but the empty space at the bottom is 
even larger now:
http://www.fam.tuwien.ac.at/~reinhold/temp/Pembaur_VierteLateinischeMesse_LongScore_higher.pdf

-) Figured bass has a lot of space between its staff and the figures:
http://www.fam.tuwien.ac.at/~reinhold/temp/Mozart_BenedictusSitDeus_KV117_BassoContinuo.pdf

-- 
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Reinhold Kainhofer, Vienna University of Technology, Austria
email: address@hidden, http://reinhold.kainhofer.com/
 * Financial and Actuarial Mathematics, TU Wien, http://www.fam.tuwien.ac.at/
 * K Desktop Environment, http://www.kde.org, KOrganizer maintainer
 * Chorvereinigung "Jung-Wien", http://www.jung-wien.at/