3D computer games

I have already mentioned a bit about 3D TV, and especially Sky 3D which sort of cheats by sending a normal HD picture which happens to be two side by side squashed images. The TV separates them, stretches them and presents one to each eye. It is a cunning way to use older technology to send something new. The storage, transmission, Sky box, recordings and everything sees it as just a normal HD image until your TV does the magic. In my case the TV is a large Sony which alternates the left/right image and uses active shutter glasses controlled by infra-red to block one eye at a time. Some TVs are now working in different ways and ultimately I hope they will use the cheap passive glasses like at the cinema (I think LG have one that does now).

My 3D TV has down sides - the glasses are expensive, big and uncomfortable and the batteries go flat. There is ghosting of one image on to the other. You also lose resolution by the side-by-side transmission used by Sky. That said, you can, with enough glasses, have the whole family sit and watch a 3D film and enjoy i. It works!

3D computer games are a tad different. I have a nice nvidia card with DVI and HDMI outputs (even comes with an HDMI cable). I have an Acer 24" monitor with 3D glasses. The monitor takes HDMI, DVI or VGA and actually comes with all of the cables (impressed!). The glasses are nicer, lighter, and recharge from a USB lead which you can have plugged in whilst using them. The monitor switches at 120Hz and has no bleed through between eyes at all. The glasses presumably have longer blackout periods including both eyes during the switch between images making everything else in the room rather dark - this is probably only possibly because you sit so much closer to a computer monitor, but the end result is excellent.

It is worth understanding a bit about how these games work though. Once upon a time a computer game designer worried about the pixels they produced on the screen. These days the graphics cards do all the work and the game is in fact creating animated 3 dimensional objects from triangles in space. Games like Wow are a lot more about story and artwork than graphics. Some games have a lot of back end physics engines, such as car games, but in WoW characters can just walk through each other. The graphics card does the projection in to a 2D image, and even does lighting, shadows, smoke, dust, flame, and all sorts of effects to make the image look real.

What this means is that to make a game 3D you just need the graphics drivers to plot from a slightly different viewpoint that the game says, one to the left and one to the right, and present the two views, one to each eye. The card sends full resolution 3D to the monitor, either via HDMI or DVI. The HMDI has some restrictions on frame rate and/or resolution which means it may even work with my Sony TV (to be tested later). But the Acer using DVI will do 1920x1080 60Hz and display in 3D.

Update: Tested with Sony 3D TV. Works for setup and tests, but seems to need a £25 download from nvidia to actually use it - what a con!

The game does not even know you have 3D.

In fact the game does not really care what frame rate, resolution, or capability your graphics card has. It is a smart way to do things and allows people to have cheap cards that provide a lower quality or expensive cards and large monitors for higher quality yet the underlying game stays the same. 3D just adds to this like any other clever thing the card with do. The Nvidia card has a control panel which even allows per game settings that override the defaults (such as turning on anti-aliasing - useful).

Whilst this is a really good idea - that any game using the graphics card for 3D rendering can be played in proper 3D using the glasses, there is a down side. It means the game designers do not think about 3D, or don't have to. But should this matter? Surely they are just making a 3D scene which must work else it won't look right with one eye (the normal 2D projection). Not quite.

I have played Star Wars - The Old Republic and World of Warcraft. SWTOR was clearly not designed for 3D and EA have not bothered to sit one of their designers in front a 3D screen with it. A simple and inexpensive move which would result in a handful of minor tweaks at almost no cost, but sadly not. WoW on the other hand clearly have.

So what are the issues?

The first issue is where you put the view point. When rendering in 2D it does not matter how far back you are or how close you are - that just changes sizes of things and some of the viewing angles. However, SWTOR places a lot of things in front of the monitor (close to you) - so much so that the default settings are unusable. Setting minimum depth on the nvidia controls you can finally play it, but your avatar and anything else close is in front of the monitor. That alone is not a big issue - it works, if a tad odd. Things at the edge of the screen are a tad odd if too close, but workable.

As you may expect, all of the the on-screen controls appear flat at the monitor - as a sort of heads up display - like a sheet of glass in front of you and you are looking at the scene through it with text and graphics on it. In WoW the scene is all behind the monitor so the on-screen graphics are fine as they are in front of everything. In SWTOR the on-screen graphics are visible in front of things but behind them in perspective so it breaks the 3D effect. Even the mouse pointer in front of your avatar is horrid, and I kept moving it out of the way during many of the graphics sequences as it appears in a sort of double vision effect and is just wrong. In WoW using the mouse to click on things in the distance takes getting used to as the mouse pointer is on the screen, but that is usable, and does not look wrong.

Update: top tip for WoW - turn off hardware mouse cursor. WoW will then place the pointer in 3D space and move depth depending on what is there. This allows you to more naturally point at things in the distance. Very cool.

SWTOR has a few other quirks - like the name banner over a character. It is in the 3D space, but is quite a way behind the player. It is like they wanted it a bit smaller and instead of making the font smaller they put them in the distance a bit. That is fine in 2D, but in 3D it makes it hard to work out who has what label!

So, last night, I sat next to my son playing SWTOR. It was funny as he has no idea how to play and I was telling him what to do an what keys did what even though I have never played (yes, it is just WoW with light sabres). I just got so used to the 3D, and it was excellent. Looking to one side and seeing his screen was just weird as it was, well, flat! It looked boring and strange compared to my 3D screen.

Overall - well impressed!