[tex-k] tfmload.c in dvips and xdvi

janl@linpro.no janl@linpro.no
Mon, 14 May 2001 23:46:06 +0200


Hi,

The t1 font code in xdvi needed to load tfm files to aquire precise
charater widht information.  I had a look around and found tfmload.c
in dvips.  Based on that and my reading of various Knuthian writings
I wrote this snipped in tfmload.c in xdvik:

    for (i = bc; i <= ec; i++)
	if (chardat[i] != 256)
	    widths[i] = wtab[chardat[i]];

chardat is unsigned char.  As a SunOS 4 cc pointed out this (the middle
line) makes no sense, it is always true (thanks to Stefan Ulrich for
noticing).  In dvips analogous code is found (tfmload.c also):

   for (i=0; i<256; i++)
      if (chardat[i]!= 256) {
         li = scaled[chardat[i]] ;

Persuing dvicopy.web I've been unable to find the documentation for
this.  Is there a better place? Does anyone have a ready answer?

Nicolai