In case you’re interested in the more technical side of things

In creating the wraparound screen experience, I’m utilizing a 2.2 meter tall, 3 meter wide curved screen. Now, to create such a large projected screen, a few hurdles have to be overcome:

1) Using one projector on the entire screen is simply too low resolution – too few pixels stretched over too large of a surface. So I’m going to need to use multiple projectors to create the large scale screen with the fidelity that I’m looking for.

2) The problem with projectors is that, under normal circumstances, they have to be quite a distance away from the screen in order to create a sizable image area. This is particularly difficult for the H:R project because I want people close to the screen, so that it occupies as much of their field of vision as possible. But that means normal projectors would be behind the viewer, and that means they’re casting shadows on the screen. The solution: Ultra short throw projectors. These things are amazing – they make an enormous picture while only being a few inches from the screen.

3) Adding more than one projector as a display adapter is no problem. However, it’s necessary to overlap each projected image a little bit, and “blend’ the seams so that there isn’t a “bright” area. Additionally, since projectors are designed to be displayed on a flat surface, the images become warped and distorted when they’re projected on to a curved surface. Special software is required to correct these distortions.

4) However, in order to utilize the de-warping software AND to get 3D games to utilize the entire desktop image area (as opposed to using only the full screen constraints of the primary display, which is normally the case) Each “expanded” desktop needs to be merged in to one unified desktop – and here’s where it gets tricky.

5) In order to create one big desktop area (instead of multiple side-by-side desktops) one must utilize special hardware and software. I’m going with Nvidia’s “3D Vision” solution for a variety of reasons, but ATI offers similar products. Creating a seamless desktop in this manner is something nVidia calls “3D Vision Surround Technology.”

6) In order to utilize 3D vision surround, you’ve got to have a compatible video card and the latest drivers, but that’s not all… driving one huge desktop while processing 3D images at ENORMOUS resolutions takes a whole lot of computing power. The solution: nVidia’s “SLI” technology, which allows you to link up to 3 video cards and use them in tandem with one another in order to do the heavy lifting. But there’s a catch…

7) In order to utilize SLI, several requirements must be met. You have to have an SLI compliant motherboard…. the video cards in question must be capable of utilizing SLI technology… the video cards must be linked appropriately with an SLI cable…. and my personal favorite: the video cards have to be identical in every way. I learned this the hard way, when I tried to use an GFX 570 and a GFX 570Ti together. Close enough, right? NOPE. I’m in the process of returning the 570 and replacing it with an absolutely identical GFX 570ti.

8 ) Here’s the next little caveat: Assuming you get the right hardware, get SLI working, AND get 3D Vision Surround installed and ready to go, it only works under extremely controlled conditions. Namely, you must have NO LESS THAN three displays connected. (I was originally planning on using 2, but having learned this fact I’ve upgraded to three). Additionally, all three displays must be identical – even down to the manufacturer. And last, but not least, all three projectors have to be connected in a very specific way – both in terms of the cables used and which ports on each video card they are plugged in to.

So, now I’m waiting on my matching second video card to arrive in the mail so that I can hopefully get SLI working, enable 3D Vision Surround, and configure my three ultra-short-throw projectors to create one, seamless, ultra-high resolution image that gracefully wraps around the curves of the 120 degree screen. Once I have that going, you can bet I’ll be posting some pictures. :-)


4 Responses to “In case you’re interested in the more technical side of things”

  1. In a word…..

    …..damn……..

    - StickyGum32

  2. Very interesting, and very impressive. Looking forward to seeing the full setup when you’re all finished!

  3. …SLI sounds like a terrible technology. Is there any reason at all it has to be THAT specific?

  4. Willing to bet even you won’t understand what you just said in five years.

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