[pdftex] Virtual fonts, truetype and tfm

[The Thanh Han]

On Wed, Nov 13, 2002 at 08:19:48PM +0100, Jean-Christophe Dubacq wrote:
> Hi! Does pdftex need the .tfm for the raw font when composing with
> virtual fonts?
> My ttfonts.map contains:
> ma1mn16t < ma1mn.ttf < T1-WGL4.enc
> 
> My t1ma1.fd contains:
> \DeclareFontShape{T1}{ma1}{m}{n}{<-> ma1mn8t}{}
> 
> My .vf is generated with the following line:
> ttf2tfm ma1mn.ttf -q -O -N -T T1-WGL4.enc -v ma1mn8t.vpl ma1mn16t.tfm
> (and then vptovf is run on the resulting .vpl)
> 
> According to the definition of virtual fonts and my understanding,
> pdftex should never use the information contained in the .tfm of
> the raw font (TeX composes everything with the virtual font glyphs
> and sizes, and then uses the mapping T1-WGL4.enc and the instructions
> in the .vf to find the right glyphs in the TTF file).
> 
> However, some of my friends (using pdftex-13d) claim if they suppress
> the *16t.tfm, pdftex tries to recreate them...
> 
> Any thoughts about that? Am I wrong in my understanding of the .vf
> files?

pdftex still needs the info from the raw tfm to typeset the characters in
that font. Virtual fonts don't contain metric info of characters from the
raw fonts. 

Thanh