Scenery display has a profound impact on how immersive the flight simulator experience is. In fact, we can say that for just about any game application; motor sport games are better with better graphic display, so are first person shooters, and so on. Having a great display system supports a great gaming experience.
We're seeing more and more neat technology: better projectors, better big screen monitors, stereoscopic displays, butt kicking video cards,... What seems to be missing is a guide to help choose, set up, and optimize.
Specifically, what's needed is a guide that has maximizing the game experience as the central goal.
Specifically, that's what Building Immersive Display Systems is about.
This is a work in progress. I have about 195 pages so far and haven't settled on a final page count. I haven't developed any projects yet though I probably will do so. I also don't have a price or a completion date set.
The writing is still fluid and I expect that much will change. Still, the material I've developed so far does have some structure, and it looks like this:
Immersion Factors & Display Options
When the thought of scenery display comes up, often there's a nearly immediate leap to a solution. It might be to a video projector, because projectors are cool, or maybe to a big screen plasma display, because HD looks great, or maybe...
What happens less frequently is planning. Yes, buying a shiny new display can have a nice impact, but getting the most from a visual display system requires understanding what leads to a sense of immersion, the feeling that you're part of a virtual world. Ultimately, immersion is what a visual display system should deliver.
This chapter details the factors which are key to promoting immersion, and overviews the major technology choices you have for developing an uber-class visual display system.
When planning a display system it's remarkably helpful to have performance specifications for the projectors, projection screens, LCD or plasma displays, etc. that you're considering. Usually, the marketing literature provides piles of performance numbers. It's even more helpful to understand which of those number have a real impact and which are marketing fluff. This chapter provides the information necessary to cut through the marketing crap.
The first half of this chapter covers the real ANSI definitions of topics like brightness and contrast. The latter half covers what the human eye is actually capable of. The ideas here are to understand what a product actually does, and to know what performance factors will have a worthwhile impact on the final image quality of the completed display system.
We're all familiar with projection systems if only from going to a movie theater. It all looks deceptively simple. Projector goes at one end of the room. The screen goes at the other. If there's no screen, a light color wall will do in a pinch. Things get a little tricky when we want a video surround or if we want to get the most out of the system, but even so, it's not rocket science.
At least, it's not rocket science if you know what a projector is capable of, what impact projector location has on the image, what the screen is actually doing, and how screen shape affects image quality. When you know these things you can configure a projection system that truly enhances the game experience.
Presenting that knowledge is the goal of this chapter. It covers the common projector designs, along with their respective strengths and weaknesses. It covers screen technology, including screen paint, and describes the key performance factors and their impact on image quality. It also covers the impact of different throw distances and throw angles.
Direct View Displays
Direct View Monitors covers computer monitors and, well, actually these days every monitor is a computer monitor. Some have a computer connected to them, some have computer controlled television receivers connected to them, and some have computer controlled recording and playback devices connected to them. Anyway, a multiplicity of monitors can produce an impressive display. There are still issues such as delivered contrast versus spec'd contrast, so it's not a totally trivial undertaking.
Head and Helmet Mounted Displays
HMDs are good choices when you want to emulate the experiences of real-world pilots, war fighters, and search and rescue crews. They are also good alternatives to consider with space constraints make larger displays system unworkable.
The HMD experience is more than just looking at a small display disguised as a heavy pair of glasses. HMDs in military applications are generally coupled with a system that tracks the position and orientation of the viewer's helmet. Data from this tracking system is used by the image generating system to control the virtual view point, and by the weapons systems for aiming.
This chapter overviews real-world military HMDs and describes pertinent performance factors to look at when considering the purchase of the recreational variety. It describes the basic principles of tracking systems, and maybe, just maybe will have a tracking project.
Three-D has made a big push into movies over the past few years. It's also beginning to drift into home entertainment systems. Done well, it adds to the reality of the experience. Done poorly, or used in the wrong situation, it's a distraction and waste of money.
The key is making an informed choice. This chapter explains how several stereoscopic display technologies work, what each does well and not so well.
Collimated displays are the mainstay visual display systems of commercial flight simulators because they provide the same perspective view regardless of viewing position within the simulator cabin.
Applied to a game situation, a collimated display creates a greater sense of distance. You're not looking at a monitor two feet away or even a projection screen several feet away. You're looking at an image way, way out there. A collimated display allows you to squeeze a very real looking horizon-to-horizon view into a medium size room.
This chapter digs into the technical details because if you want a collimated display you'll have to build it yourself, unless you've got a lot of money and a very understanding spouse.
Just because the chapter gets technical does not mean you need an engineering degree to read it or understand it. The optical design of a current day collimated display is really quite simple because these systems have been refined and simplified over the years. You can rough out a design for a collimated display using a pencil, a straightedge, and a compass. (Personally, however, I prefer using an inexpensive CAD system like TurboCAD.)
The chapter describes what a collimated display does, as well as, how it does it. It provides the necessary optics background, using a graphical rather than mathematical approach, and shows how to do ray tracing with basic CAD software. It includes a design study of a panoramic collimated display scaled for recreational use.
Head Up Displays
Head up displays paint a virtual image of navigation and targeting information on top of the real-world outside view. Originally used in war planes, HUDs are now found in commercial airliners and some cars.
In a game application the HUD data could simply be added to the video for the outside view, but that would be short on realism. Move your head sideways enough while using a real HUD and the image disappears. If you're aiming for the ultimate visual experience, you'll want the real HUD experience. This chapter shows you how to get it.
Back in the first chapter overview I mentioned that "The idea is to take total control of the visual field and promote total immersion". It's unlikely you'll have a display system large enough to fill your complete field of view. What happens outside the boundaries of the display system can be as important as what happens inside.
Small happenings outside the display system boundaries can be massive distractions that become the limiting factor in the overall game experience. To support suspension of disbelief, block out those small happenings.
This is a rare situation where it's a good idea to think inside the box. More specifically, think about using an enclosure.
Detailed coverage of enclosures is outside the scope of this book, but the topic is an important one. So, what we've got here is a short chapter introducing an important subject.
Video Sources presents general approaches to supplying the video needed to run an immersive display system.
Taken together these topics provide fair coverage of the issues that computer game players face when striving to get the most out of their applications. I plan on developing more material to cover these topics in depth.