Path: utzoo!utgpu!water!watmath!clyde!att!ucbvax!CORY.BERKELEY.EDU!dillon
From: dillon@CORY.BERKELEY.EDU (Matt Dillon)
Newsgroups: comp.sys.amiga
Subject: Re: Next Amiga system
Message-ID: <8810030229.AA19219@cory.Berkeley.EDU>
Date: 3 Oct 88 02:29:51 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 36

Peter da Silva  peter@sugar.uu.net Writes:
:too many problems for the software. Either 8-bit DACs or 6+2 HAM. Can people
:really distinguish more than 6-bit DACs can provide? I don't believe they
:can handle more than 6-bit greyscale (based on an old Ciarcia article).
:-- 

	Many people get confused between a lack of DAC resolution and a 
lack of color registers.  As we have seen comparing HAM images to standard
color-register-based images, it is the lack of color registers that makes
granularity the most obvious.  HAM images almost eliminate the color-register
problem so one essentially sees only the DAC resolution problem.

	6 would be an improvment, but not a great enough leap to be meaningful.
8 is the bare competitive minimum for today's market (8 bits per gun that is).
I.E. the 24 bit plane Mac II cards usually do it this way, getting rid of 
color registers entirely.

	Also, the way things are moving, having screen memory part of the
computer's main memory will no longer work.  Sure we should map it in, but 
to get the bandwidth required it must be more dedicated (on the video board
itself).  For the next class of machine, we want to remove the video DMA
completely out of the computer's motherboard.  I would still like to keep
CHIP memory, but use it instead for a multi-channel general DMA chip...
Maybe 4 highspeed channels and a dozen low speed channels.

	The need for one or more blitters is quite obvious.  The Mac II
suffers in a big way due to the lack of blitters on both Apple's and 3rd
Party video cards.  3rd Party cards will probably have blitters on them
in quantity by early next year.  The blitter should be part of the video 
card and not the motherboard (these last two paragraphs I've been talking
about my envisionment of some future Amiga machine).  Somebody suggested
some specialized hardware to do 4x4 matrices, I agree!  Interface it in
with one of the Math libraries as a standard function so there's no 
hardware dependence!

					-Matt