Column line spacing with individual markup-lines, via a scheme function

[Jeff Epstein]

Phil Holmes <mail <at> philholmes.net> writes:
> Is it a known feature that using the font sizing commands \teeny, \huge, 
> etc., leads to inconsistent line spacing when compared with using fontsize?

%{
   As this was posted, I happened to be researching just this topic.

   I'm trying to use the below scheme-markup function, kLineSpacingTest, to
   create individual markup lines that COULD be placed inside a column, or just
   be used by themselves. The musical notes a1 and aes1, below, are the
   potential usages I'm looking for.

   Unfortunately, the line spacing when placed in a column (as in a1) is as if
   the font is--I believe--the default size. This is despite every line having a
   "#:fontsize -3". Hence, way too much space.

   Here's an image of the rendered sheet:

   http://jeffyepstein.com/posts/line_spacing_question.JPG

   The spacing for both a1 and d1 are exactly the same--too far apart. The
   others (aes1, b1, and c1) all have different spacing, which surprises me, as
   the font-sizes are all -3. I like b1 best, but any of these three are better
   than a1 and d1.

   So the question is: If every line in a column has the same spacing, why
   should the column itself impose a larger-than-necessary line-height? Is there
   a way to override this behavior WITHOUT needing the redundant fontsize
   setting between \markup and \column? Can you absolutely define markup line-
   height regardless of fontsize, and potential collisions?

   Thank you for any advice.
%}

#(define-markup-command  (kLineSpacingTest layout props s_comment)
                                                (string?)
      "Print the comment. Example usage: c4.^\\markup \\kLineSpacingTest \"a\""

   (interpret-markup layout props
      (markup (#:fontsize -3 s_comment))
   )
)

   \relative c'' {

      a1^\markup {  \column  {
         \kLineSpacingTest #"a1 1"
         \kLineSpacingTest #"a1 2"
         \kLineSpacingTest #"a1 3"}}

      r1 r1

      aes1
         ^\markup {  \kLineSpacingTest #"aes1 1"  }
         ^\markup {  \kLineSpacingTest #"aes1 2"  }
         ^\markup {  \kLineSpacingTest #"aes1 3"  }

      r1 r1

      b1^\markup { \fontsize #-3 \column  {
         \kLineSpacingTest #"b1 1"
         \kLineSpacingTest #"b1 2"
         \kLineSpacingTest #"b1 3"}}

      r1 r1

      c1^\markup  { \fontsize #-3 \column {
         "c1 1"
         "c1 2"
         "c1 3"}}

      r1 r1

      d1^\markup  {   \column {
         \fontsize #-3 "d1 1"
         \fontsize #-3 "d1 2"
         \fontsize #-3 "d1 3"}}
   }