The T-Buffer

Top enchilada

Scott Sellers, one of the founders of 3dfx and a current co-chief technical officer of the company, took over the presentation from Michael to personally explain the T-buffer. The T-buffer's primary task is to solve the aliasing problem in 3d graphics. In a nutshell, aliasing is under-sampling of an image, which causes graphical artifacts on screen. Examples of aliasing artifacts include jagged edges on polygons, and pixel popping or "sparkling" while approaching complex or finely detailed objects. The T-buffer will allow for full screen antialiasing in real time. So what you say? Other cards have bragged about antialiasing for a while now, but 3dfx dismisses those implementations are hacks which are not practical for use in games. 3dfx's implementation will work without compatibility problems or speed hit.

Antialiasing comparison

Works everywhere

The best part about "full scene spatial antialiasing" is that 3dfx's implementation will be able to work with any 3d game, past, present, and future. It's fully done in hardware, so there's no need to wait for special drivers or patches to get it to work on your games. In essence, the feature upgrades the image quality of all the games you own. That fact is a very compelling argument because normally, new features require specific implementation by software developers and we don't see how they affect games until 6-9 months down the road.

NFS3

We got to see how full scene antialiasing improved the movement and animation in Need For Speed 3. The game came straight out of the box and was run at the same resolution on a plain Voodoo 3 and on that jury-rigged system with antialiasing enabled. The results were quite noticeable and convincing on the anti aliased screen. Thin powerlines and trees in the distance were no longer jagged, broken lines of pixels as they appeared to be on the Voodoo 3. Stair stepping effects on the power poles were completely eliminated and smoothed in the anti-aliased version. The painted lines on the road were also smoothed out, enabling you to see them farther ahead on the road. Most impressive was the elimination of the "sparkly" or "popping" effect as objects in the distance get redrawn. Anyone would immediately notice the difference in how smooth games appear to play.

What else does it do

The T-buffer does a lot more than full scene antialiasing, but the other features are ones that have to be specifically implemented by game developers. Keeping in tune with the goal of "Hollywood on a desktop," the four other features were: real time motion blur, depth of field blur, soft shadows, and soft reflections. These tools will enable game developers to create the same kinds of effects that Hollywood directors use all the time when making films.