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- From: langston@memstvx1.memst.edu (Mark C. Langston)
- Newsgroups: alt.cyberpunk.tech
- Subject: Re: TV glasses and VR
- Message-ID: <1992Nov11.003531.4032@memstvx1.memst.edu>
- Date: 11 Nov 92 00:35:31 -0600
- References: <m3uVTB3w165w@freeside.com> <qqeXTB2w165w@freeside.com>
- Distribution: world
- Organization: Memphis State University
- Lines: 57
-
- In article <qqeXTB2w165w@freeside.com>, popec@freeside.com (PopeC) writes:
- > Depends on the interfaces. For VR you need a left and a right channel to
- > really work right as each may be a little different. If these glasses
- > have only one interface feeding two screens, this may be a problem.
- > Converting a VGA display to NTSC isn't a real big trick. There are
- > boards of the shwlf now that do that.
- > Once again, you need two boards, one left, one right to give you true
- > stereoscopic viewing.
- > Hacking these things to work for true stereoscopic VR may be a bitch.
- > Maybe they'll be smart on the Glasses and make a VR ready pair for VR
- > hackers.
-
- Well, I don't see it as being all that hard (or expensive). It'll just
- require a little imagination.
-
- To begin: I haven't seen the article, but I'll assume for sanity's sake the
- tuner is not an integral part of the frame (read: it's a belt-pack, pocket-
- stored walkman-type thingie, or similar). Well. We don't need a tuner, so
- bye-bye unnecessary hardware. This leaves us with two very small, very
- useable video displays with appropriate inputs (throw a few things here and
- there if you want to get nice and have modular input jacks, either digital or
- RGB for each vidmon.
-
- Okay. We've got the raw device now: a cheap hmd without directional feedback
- ...so what next? No need to get fancy. Just hack some code into whatever
- image driver you're using for the VR, so it alternately renders a full view,
- first right eye, then left, with appropriate perspective (not much, if the
- mon's are sitting 1" or so from your face...a little goes a long way...in
- fact, a general algorithm could probably be developed here).
- Now then. What do we have now? A computer generating scenes very quickly
- at alternative perspectives. Result? A mess of jittery images on your
- monitor. Now what? Simple. Throw the output to _both_ mon inputs, and wire
- up a simple circuit that's gonna alternately pass the vid signal to one eye
- at a time. Get fancy: Use the digital output of your computer, sync the
- switching to the comp's refresh rate (sync line avail on digital signal out
- of computer). What do you have now? Homebrew VR.
-
- A problem with images too flickery to be of any use? Not. I am assuming
- a) that the displays are LCD, so the decay rate of the display is going to
- be longer than the refresh rate of your comp vid out signal (although
- hopefully not so much longer that you lose updates), and b) your comp refresh
- rate is high enough to be of practical use anyway.
-
- Hook up a Powerglove (get creative...use two!), and you're off (or in?).
-
- Get even more creative: Add analog joystick mechanisms as directional feedback
- for the almost-full HMD. I'll leave this as an exercise for the reader.
-
- Have fun. Get lost.
-
-
- --
- +--------8<------Cut Here------8<------Cut Here------8<------Cut Here---------+
- Mark C. Langston | "Secrecy is the beginning of tyranny."
- Psychology Dept. | "Always listen to experts. They'll tell you what can't
- Memphis State U. | be done, and why. Then do it."
- "Pftph!" | -From the notebooks of Lazarus Long
-