24-02-2011, 02:19 PM
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3D PC GLASSES
1. INTRODUCTION
Only a few years ago, seeing in 3-D meant peering through a pair of red-and-blue glasses, or trying not to go cross-eyed in front of a page of fuzzy dots. It was great at the time, but 3-D technology has moved on. Scientists know more about how our vision works than ever before, and our computers are more powerful than ever before -- most of us have sophisticated components in our computer that are dedicated to producing realistic graphics. Put those two things together, and you'll see how 3-D graphics have really begun to take off.
Most computer users are familiar with 3-D games. Back in the '90s, computer enthusiasts were stunned by the game Castle Wolfe stein 3D, which took place in a maze-like castle. It may have been constructed from blocky tiles, but the castle existed in three dimensions -- you could move forward and backward, or hold down the appropriate key and see your viewpoint spin through 360 degrees. Back then, it was revolutionary and quite amazing. Nowadays, gamers enjoy ever more complicated graphics -- smooth, three-dimensional environments complete with realistic lighting and complex simulations of real-life physics grace our screens. But that's the problem -- the screen. The game itself may be in three dimensions, and the player may be able to look wherever he wants with complete freedom, but at the end of the day the picture is displayed on a computer monitor...and that's a flat surface.
3-D PC glasses are designed to convince your brain that you are seeing a real, three-dimensional object.
1.1 Seeing in Three Dimensions
Human beings, like most other creatures, are equipped with two eyes, situated close together and side by side. This positioning means that each eye has a view of the same area from a slightly different angle. You can check this out by focusing on a distant object and viewing through each eye alternately -- see how some things seem to change position slightly?
The brain takes the information from each eye and unites them into one picture, interpreting the slight differences between each view as depth. This produces a three-dimensional picture: one with height, width and depth.
It is the added perception of depth that makes 3-D, or stereoscopic, vision so important. With stereoscopic vision, we see exactly where our surroundings are in relation to our own bodies, usually with considerable precision. We are particularly good at spotting objects that are moving toward or away from us, and the positioning of our eyes means we can see partially around solid objects without needing to move our heads. It's easy to see why some people believe stereoscopic vision evolved as a means of survival.
Certainly, stereoscopic vision is vital for seemingly simple actions such as throwing, catching or hitting a ball, driving or parking a car, or even just threading a needle. That's not to say such tasks can't be managed without 3-D vision, but a lack of depth perception can make these everyday tasks much more complex.
2.A Different Point Of View
The key to stereoscopic vision is depth, and our brain will happily take care of that for us, providing our eyes are given the right information in the first place. This is exactly how those red-and-blue glasses work -- each color filters out part of the image, giving each eye a slightly different view. The brain puts the two different images together, and those blue-and-red blurry images turned into a fantastic 3-D comic, or movie, or TV show.
Stereograms, also known as Magic Eye pictures, use seemingly-random patterns of dots but rely on the viewer to cross his eyes in just the right way, or to look through the image until the eyes see just the right part and allow the brain to decode the hidden depth information.
Both methods have their disadvantages, of course -- the red-and-blue glasses make it difficult to show color in the 3-D image, and viewing stereograms is an art in itself. Neither method is entirely suitable for playing games.
Nevertheless, the underlying principle is exactly the same: creating and controlling those two different points of view. But just how easy is it to create these two separate images, one for each eye?
The answer is all about how games are created. Not so long ago, the graphics we saw on our computer screens were carefully drawn into the computer -- every single frame of animation, every different view of a character. If you wanted a dinosaur in your game, you sat down and drew the different views of a dinosaur into the computer.