Introduction

Earlier this week NVIDIA made quite a splash with their announcement that they were partnering with Havok to bring physics acceleration to their latest GeForce 6/7 GPUs. According to the PR, through Havok’s GPU-accelerated “effects physics” SDK dubbed Havok FX, Havok plans to use Shader Model 3.0 GPUs to simulate “the interactions of thousands of colliding rigid bodies, a fundamental technique of physics computation seen in today's latest games. It's now possible to compute the components of friction, collisions, gravity, mass, and velocity, that form the basis of rigid body physics.” NVIDIA made it pretty clear that Havok FX won’t affect gameplay objects, rather objects in the environment that don’t affect gameplay.

Say for instance, you toss a grenade into a room and it explodes. With Havok FX, the GPU will simulate the collisions of thousands of objects within the room once the grenade explodes (shards of glass, boxes, papers, etc).

What wasn’t as clear was ATI’s position on the technology. With this in mind, we inquired to the powers that be at ATI earlier this week for their thoughts on GPU-accelerated physics. If you recall, ATI first demonstrated physics acceleration during the R520 (Radeon X1800) launch last year. ATI’s Will Willis gladly agreed to answer our questions. The following is the complete text of our email exchange, which has taken place over the course of the past few days with Will at GDC:

FiringSquad: In light of NVIDIA’s announcement with Havok today on using HavokFX with GeForce cards, we were wondering if you guys had a response to NVIDIA? Is ATI working with Havok on getting Havok FX working with ATI’s shader model 3.0 Radeon X1K line? Have you looked into running this with CrossFire? Will you be working with Havok on getting Radeon support integrated into Havok FX, or do you plan on going your own way?

Will Willis: Regarding Havok, while we’re not making any announcements at the show, I can tell you that ATI will support all major physics engines. The beauty of ATI’s X1K architecture is that it gives game developers unmatched processing power for physics – it’s got everything you need to push parallel processing hard: powerful MIMD multithreaded engine, strong performance in dynamic branching, and low latency. All that gives developers the creative freedom to push the limits of realistic physics in their games. So we’re supporting the big players, and we’re delivering superior performance. As for specific cards and CrossFire, you can bet that we’re exploring all the options when it comes to physics on the GPU.

Havok itself has said that they’re a cross-platform software provider and that they don’t want to lock developers into any one specific hardware choice. They also recognize the strength in using the GPU to handle game physics. So all that said, you can probably see where this is going, but right now ATI isn’t announcing anything specific.

We will be talking about physics on the GPU behind closed doors at GDC, and if you’d like I can send that presentation to you later this week. It goes into more detail on the differences hardware can make in driving physics performance, and where ATI is aiming to take this market going forward. I’ll also make sure to get in touch as we get ready to make some announcements on this stuff down the road.