riscy
[Top] [All Lists]

Re: video (and more)

To: riscy@pyramid.com
Subject: Re: video (and more)
From: caret@pyramid.com (Neil Russell)
Date: Thu, 1 Jul 93 13:27:13 PDT
In-reply-to: <9307012021.AA13601@gossip.pyramid.com>; from "Mark Hahn" at Jul 1, 93 3:46 pm
> Wim van den Berge said:
> > Personaly I think you're wrong, I think there is plenty to be gained from
> > a graphics solution which contains a hardware BITBLT and LINE DRAW engine.
> > If I remember correctly these two functions comprise between 50 and 85 
> > percent
> > of the overhead in a non accelerated windows environment. That a lot, even 
> > for the fast MIPS CPU.
> 
> Nope.  Read the papers; the critical path is ALWAYS memory bandwidth,
> and the r3k solution will, if anything, have a better memory interface.
> 
> regards, Mark Hahn.

Also, there are algorithms that when combined with an instruction cache
(which our r3k's have) that will bitblt at 100% of the memory bandwidth
once the code is in the I-cache.  That is, we can easily equal the performance
of a hardware blt'er.

-- 
Neil Russell            (The wizard from OZ)
Pyramid Technology                      Email:  caret@pyramid.com
3860 N. First Street                    Voice:  (408) 428-7302
San Jose, CA 95134-1702                   FAX:  (408) 428-8845

 

<Prev in Thread] Current Thread [Next in Thread>