Re: "Star Wars" demo?

[sirius@spirit.com.au (Michael Hickey)]

In article <31AECD9C.41C67EA6@sci.kun.nl>, Doede Boomsma
<dboomsma@sci.kun.nl> wrote:

> Michael Hickey wrote:
> 
> > It occupied all of a Apple 40SC Hard Drive, and used a patched ProDOS to
> > get over the 32mb partition limit.  As mentioned by Leif, it was put
> > together to demo the new Apple High Speed SCSI Card's  DMA ability and 
> 
> Okay, here we see it again.. Prodos patch for the 32kb limit! I'd like
> to obtain that prodos patch (if possible). It would be great to have
> larger partitions for my BBS...
> 
> 2nd: would it also work on a Ramfast THAT fast?
> 

Hmm this appears to need some extra attention.

The "Star Wars" demo was just that, a demo.  It was specifically written
to do one job, and one job only.  To achieve the 30fps rate for the demo,
Apple wrote a custom program to read in each frame and dump it via DMA
straight into the display area.  You could probably do the same sort of
thing with a RamFAST - but the demo's been done... why bother?

I was told that the patched ProDOS was a one-off hack, designed only to
support the demo (OR it was a "lie" concocted by the Tech I spoke to, just
to keep me from pestering him about getting a copy of the demo).

A quote from Volume 6 No 8, Sep 1990 of A2-Central...

" SHOW THE WORLD THE POWER OF APPLE PERIPHERALS.  Matt Gulick, Apple
Computer's "Apple II SCSI Guy," showed the now-fabled demo where several
hundred frames from The Empire Strikes Back are displayed on a IIgs from
their digitized form on a SCSI hard disk.  Using the new Apple II
High-Speed SCSI Card and a command available through the GS/OS driver for
the card, the interface is instructed to loop through a file containing
the sequential frames from the movie, loading each successive frame into
the display buffer of the IIgs using direct memory access.  The card
achieves this at its full 1 megabyte per second rated throughput, giving a
display rate slightly faster than 30 frames per second.  The display is
quite remarkable; one tip-off is that the sequence is not shown in color
(the color palettes would be loaded "out of step" with the images, so a
static gray scale palette is used.)"

MH

-- 
                 Michael Hickey, Canberra, Australia
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