\version "2.13.1"
% \paper {
%   ragged-right = ##f
% }


\markup \justify{Here, the hairpin is way too high due to the up-stem of the first note and 
the fact that the bounding box is a rectangle}
\relative c'' { \key g \major \dynamicUp
  \stemUp b2\< \stemNeutral e,4 b | c2 e4 e | e2 d | e2\!\f d
}


\markup \justify{Setting the y-offset of the DynamicLineSpanner moves the hairpin, but
it only works if I set the y-extent to an invalid value, which removes
the hairpin from the skyline and the collision detection, too!!!}
hairpinOffset = #(define-music-function (parser location posY) (number?)
#{
  \once \override DynamicLineSpanner #'Y-offset = $posY
  \once \override DynamicLineSpanner #'Y-extent = #(cons +0 -0.01)
#})
\relative c'' { \key g \major \dynamicUp
  \hairpinOffset #3.5
  \stemUp b2\< \stemNeutral e,4 b | c2 e4 e | e2 d | e2\!\f d
}


\markup\justify{A cross-measure hairpin ends at the measure-end, but it is so long that the
bar number will be moved up very high -> UGLY!!!}
\relative c'' { \dynamicUp \override Score.BarNumber #'break-visibility = #'#(#f #t #t)
  \stemUp b2\< \stemNeutral e,4 b | e2\!\f d
}

\markup\justify{A line-broken hairpin collides with the accidentals of the key signature and
will be shown way too high.}
\relative c'' { \key g \major \dynamicUp
  b2\< \stemNeutral e,4 b | c2 e4 e |\break e2 d | e2\!\f d
}





\markup\justify{The dynamicsAllInside function makes it possible to move dynamic signs inside
the staff, but how can I move a hairpin up/down? I only manage to do it by also setting the Y-extent to an invalid value, which will completely ignore the hairpin for the vertical layout -> possible collisions, since the hairpin will be outside the skyline.}

\relative c'' { \dynamicUp 
  c2\pp\< a4 b | e2\!\f d
}

dynamicsAllInside = #(define-music-function (parser location offsetX posY)
(number? number?)
#{
  \once \override DynamicText #'X-offset = $offsetX
%   \once \override DynamicText #'Y-extent = #(cons 1 -1)
  \once \override DynamicLineSpanner #'Y-extent = #(cons +0 -0.01) %#(cons 1 -1)
  \once \override DynamicText #'Y-offset =
    $(lambda (grob)
       (let* ((head (ly:grob-parent grob Y))
              (offset (ly:grob-property head 'Y-offset)))
         (- posY  offset (- 0.6))))
#})
\relative c'' { \dynamicUp 
  \dynamicsAllInside #-2 #3 \once \override DynamicLineSpanner #'Y-offset = #4.4
  c2\pp\< a4 b-.-> | e2\!\f d
}



\markup\justify{The dynamicsAllInside function completely removes the dynamic sign
from the skyline, so that collisins will occur. I'm now looking for a way to 
move the dynamic sign inside the staff, but let it count towards the skyline and
also use the part above the staff for collision prevention. In particular, the tempo mark is aligned as if the \dynamic ff is not there at all!}

\relative c'' { \dynamicUp \tempo "Langsam" 4=60
  \dynamicsAllInside #-1 #1.5 b2\ff c4 c | e2 d
}