[comp.text] Slitex colour layers wrong

richard@aiai.ed.ac.uk (Richard Tobin) (08/09/89)

I've just installed slitex, and it seems to work for black and white,
but when I try to produce colour layers the layers don't match.  The
gaps are much too small for the text from the other layers.  In fact,
it looks as if the invisible characters have zero width, and only the
interword spacing is there.

Is this a known problem?  Am I doing something stupid?  Send me mail,
and I'll summarise.

Relevant facts:

  TeX, C Version 2.9
  SliTeX Version 2.09 - Release 10 November 86
  dvi2ps VERSION "2.10gf"
  Apple laserwriter

And here's the code:

/tmp/root.tex:

\documentstyle{slides}
\begin{document}
\colors{red,black}
\colorslides{slide}
\end{document}

/tmp/slide.tex:

\black
\begin{slide}{red,black}
Here is {\red some red text,} some black text,
{\red some more red text,} and another bit of
black text.
\end{slide}

Thanks in advance,
  Richard

-- 
Richard Tobin,                       JANET: R.Tobin@uk.ac.ed             
AI Applications Institute,           ARPA:  R.Tobin%uk.ac.ed@nsfnet-relay.ac.uk
Edinburgh University.                UUCP:  ...!ukc!ed.ac.uk!R.Tobin

richard@aiai.ed.ac.uk (Richard Tobin) (08/23/89)

In article <707@skye.ed.ac.uk> I asked about non-matching colour layers
in Slitex.  As promised, here are the responses:

Chris Torek <chris@edu.umd.mimsy> :

  Chances are that your invisible characters *do* have zero width,
  possibly due to a bug in dvi2ps.  Very old (pxl file) invisible
  fonts had zero width metrics due to a bug in Metafont78, but as
  far as I know those have all been squashed.  More likely the dvi2ps
  that you have avoids sending empty glyphs to the printer, but forgets
  that having done so, the printer has not advanced; or else the printer
  itself avoids executing empty glyphs, but having done so, has not
  advanced, and dvi2ps thinks it has.
  
  All of this should work in my version of dvi-to-postscript, whihc
  should be available `soon' (I am still editing documentation and
  occasionally making small changes).
  
  
rusty@edu.berkeley.garnet :

  Try using a different version of dvi2ps.  Your problem sounds like the
  spacing problems I was having with dvi2ps.  I use dvips (no 2 in the
  name) available via anonymous ftp here in the states from
  labrea.stanford.edu.

"fw.clarke" <mafred@swan.pyr> :

     I read your news item about a problem with SliTeX a few days
  ago.  Now I seem to have the same problem myself.
  
  Reading  ../tex82/LaTeX/LaTeXslitex/README  it seems to me that
  the problem is with the driver not recognising invisible fonts:
  
   > Make sure your output driver is capable of handling files
   > with all zero rasters before you use the invisible fonts.
   > A good test is to try out cmtex10 or cmsa10 and ask for
   > \char32.  This is a zero raster character, and if
   > your driver can handle that it can handle invisible fonts.
  
Since I'm in no hurry for a solution, I'll wait for Chris's 
dvi-to-postscript (which he will presumably be working on when he gets
back from the dentist :-).

Thanks to all who responded.

-- Richard
-- 
Richard Tobin,                       JANET: R.Tobin@uk.ac.ed             
AI Applications Institute,           ARPA:  R.Tobin%uk.ac.ed@nsfnet-relay.ac.uk
Edinburgh University.                UUCP:  ...!ukc!ed.ac.uk!R.Tobin