Tessellation Unit Evolved
The hardware tessellation unit was one of the most questionable parts of ATI Radeon HD 2000 and HD 3000 graphics processing units. The tessellator consumed a part of transistor budget, but did not provide any benefits at that time, moreover, at the same time ATI/AMD made a rather controversial decision to rely on software multi-sample antialiasing (MSAA) resolve, which many considered as one of the main performance handicaps of the two families. A year has passed and the tessellation unit got evolved.
Back in May, 2007, it was a big surprise for us that the developer decided to program the tesselator using vertex shaders, not using DirectX 10 geometry shaders. At that time ATI explained that the ATI R600’s tessellation processor was taken from Microsoft Xbox 360 game console, which features DX9-class graphics chip developed by ATI Technologies. The tessellation unit of the ATI RV770 graphics processing unit can be programmed by both geometry and vertex shaders, hence, it is completely backwards compatible.
According to officials from AMD’s graphics product group, there is a number of games that take advantage of ATI’s programmable tesslation unit incoming and all of them were developed on ATI Radeon HD 2000 and HD 3000 hardware, which means that quite a number of end-users will be able to enjoy improved image quality and, perhaps, even feel themselves happy for choosing ATI Radeon over Nvidia GeForce.
But while the actual video games are enroute, those who have ATI Radeon HD 3000 or 4000 may enjoy The Froblins demo, which uses DX10.1’s global illumination technique, HDR, lighting and post-processing along with tessellation for frogs-goblins and terrain. Moreover, in the demo ATI Radeon HD hardware can even compute artificial intelligence, something new for graphics processors, isn’t it?