Path: utzoo!utgpu!water!watmath!clyde!att!pacbell!ames!umd5!eneevax!lbruck
From: lbruck@eneevax.UUCP (Lewis S.Bruck)
Newsgroups: comp.arch
Subject: Re: Bitblt chips and things (was Re: Self-modifying code
Message-ID: <1627@eneevax.UUCP>
Date: 15 Jul 88 01:56:41 GMT
References: <5254@june.cs.washington.edu> <76700032@p.cs.uiuc.edu> <1090@ficc.UUCP> <1110@flatline.UUCP>
Reply-To: lbruck@eneevax.umd.edu.UUCP (Lewis S.Bruck)
Organization: Elec. Eng. Dept., U of Maryland, College Park, MD 20742
Lines: 36

In article <1110@flatline.UUCP> erict@flatline.UUCP (j eric townsend) writes:
>In article <1090@ficc.UUCP>, peter@ficc.UUCP (Peter da Silva) writes:
>> hardware. This is what the Commodore Amiga does, using a chip called
>> the Biltter. I'm pretty surprised that a chipset this good that's cheap
>
>Isn't this in essence what CBM did with the "sprite"s on the Commodore
>64?  (Can I mention that machine in this group?  I didn't think so. :-)
>
>For those that never toyed with the 64, it has a graphics chip that
>handles from 0-8(? I think 8) MOB's called "sprites" (stupid name).
>You tell it what the MOB looks like, then just tell it to move the
>MOB.  It handles multi-color (out of 16), foreground/background, and
>automatic collision detection.  I was amazed to find that IBM PC's,
>Apple II's, and the other early C64 competition didn't have this capability.
>
>Anybody know what home/micro computer did it first?  I'm pretty
>sure the Vic-20 could do this, but I'm not sure about the PET.
>

I believe tha the first (or at least one of the earliest) was the old 
ATARI 400/800, which had a system called player/missile graphics which had
quick movement independent of actually manipulating display memory and
collision detection.  The chipset was designed by Jay Miner, who also designed
the Amiga's chipset.

Sprite (or PM or MOB) graphics are different from the blitting that is done
on the Amiga.  The sprites are independent of the display memory, acting as
an overlay, while the blitter actually manipulates display memory (and any
other memory in it's address space).  While the sprites are faster, they are
limited in terms of colors and width of image, while the blitter is a more
general purpose device.

------------------------------------------------------------------
Lewis Bruck
lbruck@eneevax.umd.edu
Not officially representing anybody, anywhere, for any reason