From: aa399@cleveland.Freenet.Edu (Len Stys)
Newsgroups: comp.sys.atari.st
Subject: Re: Blitter - what does it do besides bitcopy?
Date: 24 Dec 1992 03:40:27 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: aa399@cleveland.Freenet.Edu (Len Stys)
NNTP-Posting-Host: thor.ins.cwru.edu


In a previous article, hyc@hanauma.jpl.nasa.gov (Howard Chu) says:

>In article <1gvg4tINNqmm@usenet.INS.CWRU.Edu> aa399@cleveland.Freenet.Edu (Len Stys) writes:
>>
>>Which chip is responsible for the STe's hardware scrolling?
>
>The video shifter chip. All of the STe shifter's capabilities are also
>present in the Falcon's video chip.

There wouldn't be anything else included in the Falcon's video chip
such as scaling or rotation?

>>
>>Most other game systems use a very fast graphics chip to take care of
>>the sprites, scaling, scrolling, etc.
>
>The blitter does fine for sprite manipulation. I think it also serves for
>scaling (but not certain there). Scrolling is already handled by the video
>chip.

I realize that scrolling is, but how can we find out if scaling, rotation,
and other things have been added to the video chip?

Maybe I'm concerned about something that the Falcon might already have.

>>
>>My question is:  If ATARI is interested in making this system a competitor
>>in the computer entertainment market, why didn't Atari include one?
>
>The Falcon is a home computer that also can play games, not a game system
>that happens to contain a computer. Different emphasis, I'd say.

Hmm, but HOME computers are regulary used to play games.
And it would definitely be a bonus if it could really play some kick-butt
games...

Dad does work at home (types up letters, does his income tax, accounting, etc.),
Mom keeps a phone list and does other things similar to dad.

And what do kids do?  Which usually out number the parents?

They MIGHT type up their papers, but I bet that they play games more
than anything.

And is there any chance that Dad or Mom will play any games?  Certainly.

Entertainment should be a major issue for HOME computers.

>>
>>The SNES has a CPU speed of 3.58 MHz!  Everyone looked at this speed
>>and laughed, but the graphics chip showed that the speed of the processor
>>did not matter too much at all.
>
>Well, a 6502 (er, 65816) is a pretty efficient chip, as microprocessors go.
>Almost all its instructions execute in a single clock cycle. In contrast,
>the fastest 68000 instructions all take 4 clock cycles, and the average
>cycle time is out around 6 cycles. Given this disparity, it's plain to see
>that clock speed alone isn't enough to judge anything, and anyone who looks
>solely at speeds to judge systems is an outright fool.



Tell me that a CPU running at 3.58 MHz could be fast enough without
any help from that graphics coprocessor inside...

I don't think so Tim! :)

>
>>The Sega Genesis is based on a 68000 CPU at the speed of 7.6 MHz.
>>This system pretty much relies on the programmer for rotation, etc.
>>BUT I'm pretty sure it still has a graphics chip.  And I'm POSITIVE
>>that the Sega CD-ROM player has an especially designed graphics chip
>>for rotation.
>>
>>Recently, Nintendo announced to the world that it has developed a graphics
>>chip that will be powerful enough for 3-D imaging.
>>
>>If the Falcon030 does NOT have a graphics chip that is responsible for
>>these features, won't the video game systems pass this system by?
>
>Neither the PCs nor the Macs have any hardware-assisted graphics to speak of.
>I.e., no blitter, no sprite generator, no fine scrolling either vertically or
>horizontally, very limited video memory constraints. Games are written for
>these systems all the time. It seems to me that you're being a bit over
>concerned about one minor detail (especially when there are so many other
>major details to be concerned about, like, when will the Falcons actually
>be for sale in the US?)

First of all, the only reason games are written for the PC is because
there are millions and millions of the out there.

Atari won't have that advantage.

Another thing, Mac games aren't exactly fantastic...

But the Amiga500 (though people will disagree with me) actually put
Commodore on the map due to everyone buying it for games.

I know three people that bought it mainly for the purpose of
entertainment even though they also use it for word processing, etc.

I'd say that a home computer's abilities where games are concerned
is very important.

Though, I can't agree with you more about the shipments of the Falcon030...

WHEN???



>
>As a final note, there are already a huge number of arcade shoot-em-up
>games on the plain ol' ST, which doesn't even have a blitter. Most of them
>look pretty good. What's the problem?

The problem is that most of them won't work on the STe because they
"broke the rules"... :)

>>
>-- 
>  -- Howard Chu @ Jet Propulsion Laboratory, Pasadena, CA
>
>There's a narrow border between genius and insanity, but I'm a dual citizen.

By the way, you said what good would a 64-bit RISC graphics coprocessor
do anyways?

I'm not sure.  I don't think I could imagine what that thing could
possibly do for the purpose of entertainment, video production, CAD, etc.

But I bet if Atari ever managed to connect a Virtual Reality helmet
to a system with it, there would be some great times.

>

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