Re: Thoughts about Second Sight

[philip@labtam.labtam.oz.au (Philip Stephens)]

Christopher writes:

>There seems to be plenty of enthusiasm out there concerning the
>Second Sight board from Sequential Systems. However, I tend to
>ask the question: Is it really worth it?

  I think you're being too pessimistic, but let's take your points one at a
time:

>First, the promised JPEG display software that was said to ship with the
>board is not available in the final version.

  So???  It won't take that long for a complete JPEG and GIF viewer to be
released.

>The board is too slow to manipulate pictures in modes beyond 320x200x256.

  Let's get some facts noted down here.  Let's assume we want to update a
full screen in each of the video modes.  Here's the maximum frame rates we
would be talking about assuming we're pushing 3Mb per second:

  320x200x256:	50 fps
  640x200x256:	25 fps
  640x400x256:	12 fps 

  So obviously if you were trying to write a game that had to update the whole
screen, then resolutions above 640x400x256 would start to show jerkiness.  But
how many PC games do you know of that use resolutions higher than this, hmmm?
Not that many, I bet!

>But what about the 320x200x256 mode?  Even in this mode, you won't be able
>to do a smoothly scrolling (60 Hz) full screen action game.

  Now this is plain wrong.  See above: 50 fps should be possible, maybe even
higher if you use the SVGA controller to do the read-modifify-write operations
for you.  Remember that the GS can be doing the rest of the game processing
(which is typically not much) while the Z180 is pushing pixels around for the
current frame.

>A game like Doom also won't be possible on a Second Sight GS.

  Agreed, the 65816 isn't up to the task of doing Doom full screen at 12 fps.
But then why expect the impossible?  

>...but is all this worth spending $180 for the card PLUS several hundreds of
>dollars for a new monitor?

  Look, there is a really simple answer to your question: if you don't think
the Second Sight will be worth it, don't buy the thing.  It's as simple as
that.  But frankly, I just don't agree with your pessimistic outlook.  You're
judging the card before anyone has even had the chance to program for it.
Do you think we can write games and applications for it overnight?  Hmmm?
Wait a year, then tell me whether you think it was worth it.  You might be
pleasantly surprised what you find.

>What about this 15 FPS limitation?

  Oh-oh.  Know I see where your misconceptions come from.
  
  Christopher, you are quoting the frame rate of the SHADOWED VIDEO MODES.
That's the modes the GS already has.  Any GS programmer worth his salt will be
able to achieve much higher frame rates for games and applications by making
use of the Second Sight directly.  There is sufficient video RAM on the card
when using the lower resolutions to stash pixmaps and sprites for fast
transfers.  Don't underestimate what will be possible.

  Frankly, people who can only be negative about the GS ought to consider
selling theirs and buying the latest PC.  The GS is for enthusiasts, those who
aren't slaves to the notion that they must have the fastest and greatest
computer on the earth.  I love my GS, I think it's a great little computer, and
a lot of fun to use.  The Second Sight board will just make it more fun to
use, and that's all I can ask for.
-- 
=========== Philip Stephens, Systems Programmer, Labtam Australia ============
====== Owned by Motor (Mo for short), the power-purrer from Down Under =======
== DS (B+S+O+W)t Y 2.5 X  L W C+++ I T++ A+ E H++ S+ V+ F Q++ P B PA+ PL+++ ==
"Many views yield the truth.  Therefore, be not alone." -- Viggies' Prime Song