Truform - One of the biggest beefed up features of the Radeon 8500 is Truform. I personally find this new technology one of the most interesting of this videocard release. It's a new technology that brings realism one step closer to the virtual 3D world. The following information was build for the bigger part based on authentic ATI documents. A problem with most 3D games is that objects and persons can look 'blocky' .. Basically these are geometric blocks with textures painted on them. This blocky computer generated world is generally a result of limited bus and memory bandwidth. Truform is the hardware implementation of the high order surface technology developed by ATI known as N-Patches (DirectX 8/8.1) or PN Triangles (OpenGL). This technology enables game developers to create a virtual world which is more lifelike by smoothing out the silhouette of characters and enhancing the lighting effects. This creates a environment that looks more natural and photo realistic.

This Technology is very flexible in that it can support current shipping games as well as future games. For current game, the game developers only need to create a patch which enables the feature to be turned on if the game detects a Radeon 8500. This benefit is clearly shown with the bundled games with the Radeon 8500. The Valve Software games bundled with the Radeon 8500 all have Truform enabled and Valve will also release a patch to the existing install base of their games to enable Truform on Radeon 8500 graphics cards.

The way that Truform works is by taking the present model that developers create for games such as these dolphins in the image below. The content that developers create for today's game would consist of about 40 polygons, just like this particular dolphin.

As you can tell the light reflecting off the dolphin does not look very realistic and the edges of the dolphin look very blocky. With the help of Truform , once the model is processed through the Radeon 8500, the chip takes this model and tessellates the polygons to give it a smoother surface. Tessellation creates more polygons as seen in the illustration below, and thus creates more vertices. The increased numbers of vertices enable more accurate vertex lighting effects. This creates more realistic lighting effects that bring out the 3D nature of objects and characters.

Truform provides developers with the capability to generate smooth and realistically lit surfaces with a minimal cost in model preparation, code modification and rendering performance.