Re: Scaling global staff size without scaling Lyrics in LilyPond version 2.18.2.

[Alexander Kobel]

Hi Miroslaw.

On 2016-12-20 21:11, Mirosław Doroszewski wrote:
> \version "2.18.2"
> \include "deutsch.ly"
>
> %{
> Scaling global staff size without scaling Lyrics in LilyPond version 2.18.2.
>
> 1. It can be happen: when font size is set for lyrics, that titles are
> smaller then lyrics.
> a) I do not know how increase font size for titles. I tried some ways
> according to manuals but they did not help.

You can use
  title = \markup { \abs-fontsize #16 "Text" }
See Notation Reference (NR), section A.11.1.

> b) Changing staff size with setting font families for entire document
> (non 20pt) implies ugly effect.

Depends; ugliness is in the eye of the beholder.

> 2. When customer wants to set variable staff size and get the same
> size of lyrics for each staff size, he need to set font size of
> lyrics' context for each staff size separately.

Correct. That's by design.
To follow up on on Simon's comment about appropriate behavior on the 
list, though: we prefer the term "user" over "customer", because 
"customers" tend to pay for what they get.

> 3. For instance to get real font size for lyrics 10pt for paper size A6:
> a) when staff size = 12pt, font size overriding of lyrics = 3.7;
> b) when staff size = 16pt, font size overriding of lyrics = 1.3.

Indeed, this is non-obvious. You can use the following approach:

\version "2.18.2"
globalStaffSize = #12
#(set-global-staff-size globalStaffSize)
\layout {
  \context {
    \Lyrics
    \override LyricText.font-size =
    #(- (magnification->font-size (/ 72 11))
       (magnification->font-size (/ globalStaffSize 20)))
  }
}
{ c'4 c' c' c'}
\addlyrics { a \markup \abs-fontsize #72 a b b }

Where you replace the 12 in line 2 by your desired staff size in pt, and 
the 72 in line 8 by the desired font size in pt.

> 4. So, please, make solution and describe it in manual.

Note that I'm around for a while, but I did not bathe in the source code 
on that topic to find the solution. True: I had the ingredients in my 
mind. Not out of nowhere, but from reading the fine manuals: Everything 
used above /is/ documented in the NR, you just have to search - in 
particular, in NR 1.7.1, 1.8.3, and 4.2.2.
(Okay, except magnification->font-size; but this could be replaced by a 
few more computations. No magic in there.)

Yes, this is not the most intuitive way to achieve a fixed pt font size, 
but there are reasons.
Yes, it takes a bit of math and quite some knowledge about Lilypond's 
internals and Scheme to get there. That's the price to pay for not 
having to try different values again.
Yes, there might be other (easier) solutions that I don't know.

To repeat what Simon mentioned: this is not an appropriate tone for this 
mailing list - neither on the bug list nor here.
I reply with a solution because the answer might be helpful for other 
readers, and I hope it will be found in the archives. (Although I'm 
quite sure a similar question was there already; I did not search.) 
Everybody here is a volunteer, and you will face a lot of silence if you 
sound too demanding and use imperatives, even if prefixed by a "please".

Certainly, English is not your mother tongue, but this is no excuse. 
Most people here - like myself - are no native speakers, yet we (mostly) 
manage to be polite and humble.


Cheers,
Alexander