Physics in gaming has always been a word that nVidia has been trying to push ever since ATi brought it up and failed to act on it. After the nVidia’s purchase of AGEIA and the incorporation of the PhysX libraries into the nVidia Drivers, Graphzilla pushed its highly proprietary PhysX code onto just about every platform.

Bear in mind that PhysX is the default shipping physics code with Unreal Engine 3 and recently, Electronic Arts and Ubisoft both signed contracts about implementing PhysX in just about every major game they make. This plays into the hands of game developers that are looking for new ways to get the gamers interested in gaming again. After all – how many times can you just add eye candy to a game and get people to buy it?

Strangely, after introducing the idea of Physics on a GPU ATi [AMD] let the ball drop. In fact, Richard Huddy, the head of ATI Developer Relations even said that Physics on GPUs are dead. While this was a knee-jerk reaction to nVidia’s purchase of AGEIA, the company reacted just in the same way as when SLI appeared on the market. Now, ATi is trying to get back into the game and this mountain is going to be a difficult one to climb. PhysX has become synonymous with Physics in gaming and nVidia has done a very good job of pushing this code onto the public.

But ATi is not sitting down anymore; they have chosen a very AMD like approach, they are not going to fight nVidia and PhysX head to head. They are going to offer a viable alternative in the form of an Open platform for development – OpenCL. Again, truth to be told, nVidia had a lot to do with the initial development of OpenCL, and if there wasn’t for the impressive demonstration of CUDA running on MacOS X, Apple would never greenlight nVidia’s effort in OpenCL. In any case, there is just about enough material to make a 550-page book out of this one. To demonstrate this new non-ATi attack on nVidia’s stronghold, they chose none other than Intel owned Havok.

During this week’s Gaming Developer’s Conference in San Francisco, AMD and Havok are demonstrating Havok Cloth, a real time cloth simulation running on ATi GPUs using OpenCL. In very simple terms, this means that Havok software can now be applied to both the CPU and the GPU, making it much more flexible than nVidia’s PhysX until recently, which had to run on nVidia GPUs. nVidia had capital advantage in Ageia’s agnostic approach and started to turn it into a marketing, thus a selling point for its GPUs, which was a major mistake.

Recently, nVidia began to open up and as a result, GDC was used to announce the certification of PhysX SDK for Sony PlayStation 3 and Nintendo Wii. By leveraging OpenCL ATi and Havok shown that you do not need a single manufacturer to get your in-game Physics. This will appeal to game developers as they can code for a broader base and with standard tools. To the consumer it means games without brand limits, and to the OEMs it means freedom of choice in building AIBs and systems. In the coming days nVidia will respond; the question is what will that response be, spin or substance? My hope is for an opening up of the PhysX libraries as this will be the best situation for consumers.