Forums / Other Stuff / - Battlefield 1942 [ISR] INTERSTATE RACING - IS82 FOR BF1942

Cochrane

[ 01:04 ] [ 25 Nov 2005 ]

Registered Member #727
Joined: [ 05:25 ] [ 12 Nov 2004 ]

I'm afraid it wouldn't be a solution. The problem is always that the CPU calculates data at a different speed than the PhysX processor, and the GPU has it's own speed as well (thought that isn't as difficult, as data only flows into the GPU and hardly ever out of it again). So, say, the AI inside the CPU does calculations and the PhysX processor does so at the same time. This is not good, as the data the AI has been working with will be out of date. Another, more difficult situation is when the CPU wants to read the current physics state, again, for example, for AI or network or whatever, and the PhysX processor is computing a new one right then and there. One of them has to pause until the other is finished, otherwise everything will screw up.

None of this is new to programming in general and there are solutions (basically software versions of the regulators you proposed), but the majority of games out there is written with the idea that the programmer controls the order in which the various stages (physics, AI, networking, drawing and so on) take place. A development to do everything at the same time in various processors instead will require the game studios to invest much more money in research and it will be difficult to adapt older engines to this.

That being said, the processors of the two new consoles both encourage and require programmers to write such parallel code anyway, the X360 with its triple-core HT technology and the PS3 with its interesting/odd combination of one boring processor and eight shader-like processors per core. But that is a different topic of it's own.

About the specialized data: A second CPU will have the same syncing problems as the first one, too. However, I'm certain they have a good idea how to solve this, otherwise they wouldn't announce it as the next big thing. Maybe an approach similar to shaders (the CPU-specific parts run as special programs inside the PhysX processor) or a streaming thing, like graphics usually is, though I have no real idea what either of these would actually look like.

Teabag: No problem, it's not that I took your criticism seriously, it's just that I like to give long and boring speeches on topics like this.

Güter auf die Bahn!