How do I make expanded fonts and install them?

Question

I am running pdfTeX with dvi output. If font expansion is enabled, then I need the extra fonts, such as cmr10+20. When I try to view the dvi, xdvi tries to make various fonts and fails; the file missfont.log gets appended various commands, such as mktexpk --mfmode / --bdpi 600 --mag 1+0/600 --dpi 600 cmr10+20. If I try that command, I get an error, with mktexpk: perhaps cmr10+20 is missing from the map file. It seems first I have to modify the map file. I don't know whether that is all I have to do or not, but I don't know how to do that for a font that does not exist yet. I realize that if I used pdf output, this would not be needed. I am running Ubuntu 14.04.

Edit: In response to a request, here is a sample file. The problem will occur with any file that needs font expansion, however.

\pdfoutput=0
\pdffontexpand\tenrm 20 20 10 autoexpand
\pdfadjustspacing=2
\hsize=3in
There is a striking, but easily established, correspondence between
electrical networks and
random walks on graphs (or on networks). 

\bye

Edit 2: The fonts I am actually using most and thus would like to enable expansion for are ntx-Regular-tlf-ot1 and ntx-Italic-tlf-ot1. I would also like to enable expansion for ntxmi.

Answer 1

The autoexpand option only works for PDF output, whereas for DVI output you have to create the expanded font instances in advance. Assuming you want to use the original Computer Modern Roman MetaFont, you would have to:

• create a copy of the font source (let's say cmr10.mf),
• add a line after the place where the unit width is defined:

   u#:=20/36pt#;      % unit width
   u#:=u#+20/1000u#;  % <-- scale by 20

• rename the amended file to cmr10+20.mf.

• Repeat the above steps for as many instances as you like (e.g., -20, -15, -10, -5, +5, +10, +15).

• Repeat the above steps for all fonts that you want to have expanded (e.g., cmr12.mf, cmti10.mf ...).

When running pdftex the corresponding tfm and pk files will then be created. (BTW: You should remove the autoexpand keyword for \pdffontexpand, so as not to confuse pdftex.)

For Type1 fonts and Multiple Master fonts, the procedures are different. You can find all the details in Hàn Thé Thành's thesis, p. 370.

---

EDIT Since you are actually not using CMR, but a Type1 font, you'd have to create the expanded tfm files in advance:

• grep ntx-Regular-tlf-ot1 `kpsewhich newtx.map` tells us that the font is a reencoded Type1 font:

  ntx-Regular-tlf-ot1 TeXGyreTermes-Regular " encntx-ot1-tlf ReEncodeFont " <[ntx-ot1-tlf.enc <qtmr.pfb
  

• the base afm file is ntxtmr.afm (in fonts/afm/public/newtx/). (The base file for italics would be ntxtmri.afm, for bold ntxtmb.afm, and for bold italics ntxtmbi.afm.)

• you can create the expanded tfms with afm2tfm:

  afm2tfm ntxtmr.afm -e 1.020 -T ntx-ot1-tlf.enc ntx-Regular-tlf-ot1+20.tfm
  afm2tfm ntxtmr.afm -e 0.980 -T ntx-ot1-tlf.enc ntx-Regular-tlf-ot1-20.tfm
  

  and so on for all required steps.

• finally, you have to add the new map entries, based on the original one in newtx.map, adding the ExtendFont part (let's write them into a new file newtx-ext.map):

  ntx-Regular-tlf-ot1+20 TeXGyreTermes-Regular " 1.020 ExtendFont encntx-ot1-tlf ReEncodeFont " <[ntx-ot1-tlf.enc <qtmr.pfb
  ntx-Regular-tlf-ot1-20 TeXGyreTermes-Regular " 0.980 ExtendFont encntx-ot1-tlf ReEncodeFont " <[ntx-ot1-tlf.enc <qtmr.pfb
  

  You can then enable this map file with:

  updmap-sys --enable Map=newtx-ext.map
  

• Repeat for all steps, and for all fonts.