Re: Playing Vector Games on the Big Screen

From: Robert Mudryk <rob_at_lasers.org>
Date: Thu May 30 2002 - 11:32:41 EDT

Aaron Howald wrote:

> ----- Original Message -----
> From: "Robert Mudryk" <rob@lasers.org>
> To: <vectorlist@synthcom.com>
> Sent: Wednesday, May 29, 2002 7:31 AM
> Subject: Re: VECTOR: Playing Vector Games on the Big Screen
>
> >
> >
> > Aaron Howald wrote:
> >
> > > ----- Original Message -----
> > > From: "Robert Mudryk" <rob@lasers.org>
> > > To: <vectorlist@synthcom.com>
> > > Sent: Wednesday, May 29, 2002 12:10 AM
> > > Subject: VECTOR: Playing Vector Games on the Big Screen
> > >
> > > > Last Weekend, we got permission to do a LaserMAME demo at 6 Flags Darien
> > > > Lake, Buffalo NY... We havn't got the Video cut to images or mpeg's
> > > > yet... but here is a daylight pic of the Screen we used... approx
> > > > size of the screen is 40' x 60' (12m x 16m) in size and 20 feet off
> > > > the ground. As for Audio, there is enough Bass Bins to feel the
> > > > explosions from Asteroids at 300' away
> > > >
> > > Just too cool for words...
> > >
> > > Vector Viper
> > > ahowald@w-link.net
> > > BTW:The vector board I am building (driven with a PC) SHOULD be able to drive your laser system
> > > (the line timing can be slowed as nessary) I'd love to see the 2 projects work together
> sometime!
> > > My board puts out all analog voltages, but digital is possible. X,Y is up to +-10 volts,10
> bit;RGB=0
> > > to 10V, 8 bit each.
> > > It's totally homebrew....
> >
> > for Laser we are +/- 2.5V balanced (aka inverted signal for -) x/y/r/g/b so it should work...
> If
> > your board is a straight DAC's board, sending one point at a time... it won't work, at least with
> a
> > PC... every mouse movement or disk read/write you will get gitter in the image... I'd be glad to
> test
> > your board, for Laser or Vector Monitor, and write the MAME driver for it...
>
> My board reads (will read :*) pixels drawn to the screen as data, with each pixel being 8 bits sent.
> It is NOT a PC plug in card-you also need an older, special graphics card, I'm not sure why...(I
> have 5 stockpiled!)
> Each set of 9 pixels (1 marker, 8 data) is 1 draw command, with R,G,B,X,Y,? sent each time.
> Each of these outputs drives 1 DAC,almost all can set each cycle. Max throughput possible is 2Mhz!

very interesting approach, it may just work... 8-bit is actually plenty for most vector games, and
2Mhz, is more than enough... you just need to be able to output the frames at a fixed rate, 60fps
(200-600 Vector Points) for Asteroids and I think 20fps (1000+ vector points) for Star Wars

>
> (I am not using DAC's anywhere near that fast...)
> Line timing is set by intelligently spacing the pixel sets.
> Refresh is automatic, at the screen refresh rate or lower multiples.
> The PC sofware does do a lot of calculations for timing...
> This board is real "dumb" all control is done by the PC.

If you are relying on the PC for Timing, and you don't have a large buffer... like a entire frame or
more... the image will jitter.. with any interaction with the PC

>
>
> I can't use H or V-blank time of course! It's on odd system, but I think it has great potential; for
> vector artwork or games.
> I will post first working pics as they happen.

H/V Sync isn't necessary as you are sending the XY signal... thing you need to sync is points per
second rate, and frame rate

>
> I need to say-
> my board needs a lot of work-it may be months before completion.
> Finding time to work on it is the problem.

We have a test ISA board done, and it works well... but are working on replacing 15 components with
FPGA's right now... and then writing the PCI chipset into a FPGA is the next trick, and putting a DSP on
it for advanced Laser output, where it's going to do alot of real time rendering rather than just a
Frame Dumper.... but it defiently falls under the lines of Video Card Like, the PC is not going to be
doing any timing, only calculations post-production is maybe setting scale and generating velocity and
anchor points

>
>
> Robert, how much time have you spent on your laser system?
> I'm at 100 hours easy...Designing the hardware AND the software to drive it...nice thing is, it's
> all my own!

God.. Hours... hmmm... I've been in the Laser Show Business for about 6 Years... so probably 5-6k
hours... I've got 3 different vector output boards here, and have tried a few others... from
Parallel Port, ISA point dumpers, ISA Frame Dumpers, Amiga 2000 with modified sound board to project
laser, and Intelligent PCI Frame Dumper... about $10k in vector Output boards for the PC sitting
here... I also have contact with the majority of laser show companies, and point and frame rate
measuring is something constantly talked about... and workstations for designing shows... it cost
about $50/hour to run a Laser if not more, so working with Vector Monitors was heavily tested 10-15
years ago... due to poor quality monitor survival and lack of availability it was kinda dropped... but
I've talked to the engineers that did it, and what works and what doesn't and where we are going to find
problems...

---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.
Received on Thu May 30 08:43:50 2002

This archive was generated by hypermail 2.1.8 : Fri Aug 01 2003 - 00:34:02 EDT