How to select condensed style from font family?

[Alexander Kobel]

Dear all,

I often use a condensed font for lyrics, for obvious reasons. It's "ITC 
Garamond by Bitstream" in its condensed variant (for those who have it: 
it's in the CorelDRAW font collection).

The issue of global font change aside, that's how I can use the TrueType 
version of the font:

#(define fonts (make-pango-font-tree
                "GarmdITC BkCn BT"
                "sans-serif" "monospace" 20)

Now, I (more or less accidentally) installed the Type1 version of the 
same font on another machine, but I'm not able to find out how to select 
the condensed variant.

After some guessing, I found out the following: The TTF claims to come 
in two font families, "GarmdITC Bk BT" and "GarmdITC BkCn BT", for 
normal and condensed. The Type1 advertises itself (somewhat more 
precisely) as just the "ITC Garamond" family, with the distinction of 
condensed as a style.

So `lilypond -dshow-available-fonts x` (and, for what it's woth, 
`fc-list`) show the TTF as

  family GarmdITC Bk BT
    GarmdITC Bk BT:style=Book
  family GarmdITC Bk BT
    GarmdITC Bk BT:style=Bold
  ...
  family GarmdITC BkCn BT
    GarmdITC BkCn BT:style=Book
  family GarmdITC BkCn BT
    GarmdITC BkCn BT:style=Bold
  ...

while the Type1 is announced as

  family ITC Garamond
    ITC Garamond:style=Book
  family ITC Garamond
    ITC Garamond:style=Bold
  ...
  family ITC Garamond
    ITC Garamond:style=Book Condensed
  family ITC Garamond
    ITC Garamond:style=Bold Condensed
  ...

`fc-match 'ITC Garamond:Book:Condensed'` or `fc-match 'ITC 
Garamond:style=Book Condensed'` return (as I expected)
  Garamdnc.pfb: "ITC Garamond" "Book Condensed"
However, the same strings as arguments of (make-pango-font-tree) don't 
work. I can select "ITC Garamond", but every "add-on" does not change 
the style.
The obvious workaround is to use the TTFs, but somehow I feel that the 
naming scheme used in the Type1s is more elegant. Maybe the clumsy 
declaration in the TTFs is a technical restriction?

Long story short: Does anybody know a way to convince 
(make-pango-font-tree) to select a certain font variant or style from 
the family, or to find out how the string is interpreted? And, in 
particular: why doesn't it match fc-match's match?


Thanks in advance,
Alexander