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From: mcdonald@uxe.cso.uiuc.edu
Newsgroups: comp.sys.ibm.pc
Subject: Re: DOSTEX HELP! Please
Message-ID: <45900250@uxe.cso.uiuc.edu>
Date: 15 Jul 89 16:41:00 GMT
References: <7685@cs.Buffalo.EDU>
Lines: 27
Nf-ID: #R:cs.Buffalo.EDU:7685:uxe.cso.uiuc.edu:45900250:000:1381
Nf-From: uxe.cso.uiuc.edu!mcdonald    Jul 15 11:41:00 1989



>DVIVGA is the only PD previewer I have found that will let you preview
>LaTeX files, but to use it you need EGA or VGA graphics, a fast
>computer (286 or 386 unless you're very patient), and a fast hard with
>about 5 megs free for fonts.  DVIVGA is available on SIMTEL20 in 9 big
>archives.

I am the author of DVIVGA. Yes, it is slow. There are two reasons for this:
It needs to do a lot of disk accesses until it gets all the
characters it needs cached. This can be speeded up a LOT if you install
a good disk cache program. I use the relatively poor one that comes
with Microsoft Windows and it helps a lot (on my 386).

The second reason is that it stores bitmaps in longs instead of 
ints. This is probably a bad idea for ordinary PC's, but would be
a holy terror to change. The most recent executable has special code
for 386's that completely eliminate this as a problem by using
32 bit instructions. (It tests for 386 or 486 (I hope this is correct)
processors and does this only if it finds them.) This latter slowness
only effects displaying a given page the first time, not when using the
up and down arrow keys. (I am not going to distribute the 386 special source 
code as it requires hacking the .asm files produced by Microsoft C and uses
(bletch!!!!!) some MACHINE LANGUAGE (NOT assembler) instructions
not supported by the microsoft assembler.) 

Doug McDonald