Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!think.com!mintaka!bloom-beacon!eru!hagbard!sunic!news.funet.fi!hydra!cc.helsinki.fi!osmoviita
From: osmoviita@cc.helsinki.fi
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: video graphics cards
Message-ID: <1991Apr20.213019.6065@cc.helsinki.fi>
Date: 20 Apr 91 21:30:19 GMT
References: <1991Apr16.201903.27388@inel.gov>
Organization: University of Helsinki
Lines: 26

In article <1991Apr16.201903.27388@inel.gov>, sxb@gibbon.inel.gov (Steve Bryan) writes:
> Dear Gurus,
> 
> I am working on a (real-time) application that has fairly stringent 
> requirements for graphics throughput...

> a real-time spectrogram-type display that can transfer 25 or 30 narrow 
> (2 pixel wide by 10 pixel high) rectangles in different colors (preferably
> 256, but can live with 16) to the video card every 10ms in 640x480 mode.  I 
> _know_ that the display will not update that fast, these time slices can be 
> transferred in a batch every 30ms, if that makes it easier to conceive.  
..
> Also, if you know of any easy-to-implement VGA programming tricks that
> could be employed to speed things up, I would like to hear from you.
> I have seen some graphics done on my current board that looks fairly 
> zippy, so I suspect that more can be done with software tricks.
> 
> Thanks.                                                          

Perhaps Your card has hardware zoom. Tseng chip has it. with it you could
define for example 2x zoom horizontally and 5x zoom vertically and reduce
the amount of transferred data. I suppose you can define a part of the
screen to be zoomed and the rest to stay standard size with Tseng based
cards.

Kari Osmoviita			osmoviita@cc.helsinki.fi