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Re: Let's pay a developer to make a VGA output card

heuser.marcus@freenet.de wrote:


But do those options mimic a real display?
In most cases they don't come close, imho. If I compare a composite
picture with an emulated one there are miles between.
They simply look too perfect, too smooth and too "VGA-like".


I've suggested a possible solution, pretty easy to try in software:
use a longer shift register window.

What is missing is something closer to video DSP processing that
would mimic what an anllog composite monitor does to the video
signal.  Using a "sliding window" algorithm with a wider window
(say, 8-10bits) and a lookup table to translate colors could do
a pretty good job of emulating the low-bandwidth chroma processing
of analog monitors.  (In fact, if an 8-bit window were used, it
could map directly in the video card by using a 256-color pallette.)


On the other hand there are some very good looking video options
in emulators for other systems: VICE for the Commodore family
or Atari800Win, for example.
They have a really nice emulation of scan lines, VICE even reduces
(if wanted) the color quality to more closely resemble a tv set.
There are ZX81 emulators that even create artifacts or noise to
closely resemble what the experience is on a real machine.

Maybe its time for a differerent approach for Apple emulators.

Maybe I'm the exception from the rule but I would like to have a
highly realistic video emulation with the same quality as the CPU
emulation.


Agreed.  This is a direction that is apparently being taken by some
MAME developers, who are putting in an NTSC display emulation layer
for multiple platforms.

As PC performance rises, using more explicit DSP technology makes
perfect sense, and is capable of emulating even *specific* monitors,
like the AppleColor Composite--the "king" of analog composite monitors.


Give me a graphics option that looks like the output of an old 14''
color monitor of yore.
Give me pixels that aren't square or blocky but smear into their
neighbours.
Give me pixels that get "thicker" in height and width the more
contrast the picture has.

You get the idea.

Draw a picture in several passes if necessary, use pixel shaders
if the target platform has such advanced options. Use the power
of the modern machines - don't stay with the possibilities of the
early 90s.


Absolutely right--and exactly what DSP can deliver.

-michael

Parallel computing for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it is seriously underused."