Software Acceleration Stripped Down Effects Physics
However, this is only one part of the story. We sent the findings to Ageia, and the company came back with some interesting comments. Apparently, it did not anticipate that the hardcore early adopters would try to figure out a way to enable gameplay without the PhysX PPU. Artificial Studios only had about four months to work with Ageia before releasing the first demos. There were certain things it did not incorporate in the software-only effects physics (non-hardware accelerated) in the game. The first is the cloth and cloth tearing simulations. In the previous versions of the demo these calculations were disabled when the game was launched with PhysX disabled. This can be noticed in the pictures below.
The second item that was disabled in the demo was the fluid calculations; for example, when you shoot a toxic/radioactive waste barrel, the fluid will ooze out and form a puddle. If a second shot is fired, the fluid will explode. While the previous results show very little in the amount of frame savings in an average setting, the PPU does boost the performance when there are many objects flying around during the initial explosion. Below is a chart showing the minimum frame rates at the point of explosion. Clearly, there is an advantage to having the hardware, but we decided to rerun all of the tests from before and even add more to see how badly the lack of a PPU hurt, once the cloth and fluid simulations were added back into the demo. To note, Ageia stated that there were some optimizations added to the new demo as Artificial Studios has had more time figuring out how to offload portions of the game to the PPU.