[simpits-tech] Visual system questions (Gene) and an idea

[dabigboy at cox.net]

---- Roy Coates <roy at flightlab.liv.ac.uk> wrote: 
> On 3 February 2012 03:05, <dabigboy at cox.net> wrote:
> 
> >
> > D'oh, I meant to say "cylindrical lens". Ergo, something that would
> > distort the image evenly in only one plane, so that it could be properly
> > front-projected onto a cylindrical screen. But you are talking about
> > bouncing the projected image off a curved mirror which then projects onto
> > the screen, no? Now I have to go google "fold mirrors"! :)
> >
> 
> You've got me thinking now. I'm sure the projectors in our main sim have
> lenses mounted in front of them.  Three projectors that display onto the
> inside of a spherical chamber.
> 
> Will take camera ...
> 
> Roy.

Hehe! I would love to see the results of your experiments!

Ran across a goldmine of info on this subject:
http://paulbourke.net/miscellaneous/

One of the ideas offered here (and in fact, something the author has done many times, it appears) is using a spherical "safety mirror" (the ones typically mounted on ceilings and such, so that you can see around the corners or behind you, for instance) to bounce the projected image onto a spherical screen. The author indicates that warping software is still required, though........which leaves me to believe the only real advantage of the mirror is that it expands the FOV of the projector without losing so much focus and brightness (since the projector can be much closer to the screen, essentially). It may also reduce the amount of correction needed, but the author doesn't mention this. I wonder if a fisheye lens would be the same story. or would it work without warping software?

At any rate, I just found out that the Fly Elise people have some cheap warping software:
http://fly.elise-ng.net/

One product is even X-Plane-centric....it's a display designer which comes with an X-Plane plugin. You "design" your display in the software, and it spits out a config file for the X-Plane plugin which properly warps the graphics via an OpenGL matrix that is injected into the sim via the plugin SDK. Using an XP plugin actually occurred to me the other day, but I'm afraid my math skills are not up to the task.

One thing that particularly excited me was the screenshot of the cylindrical screen with a spherical mirror......while I'm dubious about my ability to make a good spherical screen, I think I could handle a nice cylindrical one, and the safety mirrors are cheap and plentiful. Then all I would need is three good projectors (ok, there goes the budget), and $65 for the screen designer app......hmmmm! :)

Matt