🚀 go-pugleaf

In article <PCG.90Dec12193003@odin.cs.aber.ac.uk> pcg@cs.aber.ac.uk (Piercarlo Grandi) writes:
>On 7 Dec 90 11:53:15 GMT, jeffrey@cs.chalmers.se (Alan Jeffrey) said:
>
>jeffrey> No thanks!  TeX has got to be device-independent, if you're planning
>jeffrey> to use if for serious 2000dpi typesetting, with proofs at 300dpi and
>jeffrey> previews as low as 72dpi.  TeX does a pretty decent job of placing
>jeffrey> text where you want it, it's the device drivers that often can't cope.
>
>No, this is unfortunately wrong. Currently TeX assumes an output device
>of nearly infinite precision, and with all the CM fonts and symbols. The
>problem is that no such device exists; for high resolution devices where
>CM can be downloaded the mapping from the ideal device to the actual
>device can be done in some haphazard way in the DVI driver.

Well, this is true at the moment, but `haphazard' should gradually be
replaced by `standard' as the device driver standard sets in.  And TeX
makes no assumptions (well, almost none) about the fonts you're using,
it's the plain format that does.

[...]

>In order to have the best results for type of printer one must produce
>different DVI files; it is no good to have a DVI file that was built
>assuming the printer had CM fonts with their widths and trying to
>print in Apalatino (TM) on a PostScript device. You *can* do it in the
>DVU postprocessor, but the output will be ugly, as it will have to print
>Palatino characters at positions determined by CM widths.

Certainly, in order to produce perfect output you'd have to produce a
device-dependent .dvi file, but at high resolutions you can't spot the
difference anyway (assuming you got the right .tfm file for your fonts
etc.) and you can't get perfect output out of a laser printer anyway.
Why anyone would want to print a .dvi file with font substitutions is
beyond me, except as a proofing mechanism, and it's not exactly TeX's
fault if the result of such a massacre looks rather grotty.

The problem is that TeX is designed for producing books on 1270dpi and
up printers, and it's output is rather compromised for anything else.
TeX views laser printers as proofing devices, and doesn't take much
effort about precise spacing at low resolutions.  

If you want device dependent .dvi files though, it's not that hard to
get them by a metafont hack that produces letter-widths and kerns at
multiples of the device pixel width (see how the gray font works for
details).  Inter-word spacing would still be at arbitrary precision,
but inter-word jumps aren't nearly as noticable as inter-letter jumps,
as long as you're printing on a variable-pitch printer.  If you're
living with fixed-pitch, give up and use something else.  TeX is
designed for producing beautiful books, so it's not a question of how
well the bear dances at 120dpi, but that it dances at all.

>Piercarlo Grandi 

God Jul,

Alan
-- 
Alan Jeffrey         Tel: +46 31 72 10 98         jeffrey@cs.chalmers.se
Department of Computer Sciences, Chalmers University, Gothenburg, Sweden