With the steady increase in the number of consoles being connecting to 3D televisions it was only a matter of time before we would implement support for them in our games. For the purposes of this blog I’m not going to talk about the actual implementation of Anaglyph / Stereoscopic, there are plenty of other resources available that can describe its technical aspects better than I ( www.andrewwoods3d.com I found as a good technology resource ). What I thought would be of interest to others would be my recent experiences at balancing and configuring the depth settings.

The extremes

When you first start playing around with the 3D effect, it’s so tempting (and you will do it just because you can) to push the 3D to its extremes and I promise you it will look awesome and fantastic! The bad news is that the more you push those extremes the more work your brain is doing to resolve the images and this will lead to some lovely headaches and eye strain very quickly!

The Point of Convergence

The Point of convergence is the point where the left and right eye focus and for a very good reason you will want that to be the same point as what the player is looking at. Obviously easier said than done, the technology doesn’t track the players eyeballs to work out what part of the world they are looking at so generally it comes down to best guess. Depending upon your game you can make some generalizations, i.e. a first person shooter game the player is more likely to be focusing in the distance, not on what is directly in front of them.

The solution I ended up implementing was a dynamic system that calculated the best convergence point based upon where the player is, how far he is from the camera and what at that moment in time was of most interest.

Push the depth, don’t pop it!

The truth is that the image is for all intents and purposes still 2D, the whole 3D depth effect is created because of some tricks that we play on the eyes. When you make the 3D pop out of the screen it creates an effect that causes the brain to question what it is seeing and so breaks the illusion. To solve this always push the depth into the screen, don’t try and pop it out of the screen.

Change slowly

What I personally found was that it took my eyes 1-2 seconds to adjust to large changes in depth, longer in some cases where the changes where extreme. Avoid making large changes quickly, slowly blend between values to smooth out the changes and give plenty of time for the player’s eyes and brain to catch up with you.

Equipment

Use the best equipment you can lay your grubby hands on, I started off experimenting with Anaglyph red and green glasses looking at a 24” monitor, by the end I was using  a 40” 3D television with stereoscopic polarized glasses. The difference between the two was the first one gave me headaches after an hour with the later it took much longer.

The larger the screen the more gentle it is on your eyes and certainly wearing colored glasses all day will affect your color palette when you take them off!

A Second Pair of eyes

What we discovered very early on was that a setting I loved because it looks great someone else would look at and hate. Like with art it would appear that 3D depth perspective is in the eye of the beholder, so get as many other people to look at the effect as possible if you are to find that sweet spot where it looks fantastic for everyone.

An important point to make as well is that the distance you sit from the screen has a bearing upon how the image is viewed. Make sure that anyone you ask to give you feedback sit at the same distance from the screen.

Health and Safety

Common sense really, don’t spend 8 hours of the day with the glasses on staring into the screen, take regular breaks and make sure you have some painkillers to hand.

Well that’s my lot for now.

Michael