Nanotech - The Circuits Blog

Nvidia's PhysX engine is intended to bring more realistic motion to games such as Backbreaker.

(Credit: GameSpot)

Electronic Arts and Take-Two Interactive Software are adopting Nvidia's PhysX technology, bringing more realistic gaming to the PC.

The largest graphics chip supplier is announcing on Monday that Electronic Arts and Take-Two have licensed its PhysX technology as a development platform.

"PhysX is a great physics solution for the most popular platforms, and we're happy to make it available for EA's development teams worldwide," Tim Wilson, chief technology officer of EA's Redwood Shores Studio, said in a statement.

"We are very impressed with the quality of the PhysX engine, and we licensed it so our studios can use this solution early in development," Jacob Hawley, technology director of 2K, a publishing label of Take-Two, also said in a statement.

Nvidia got its physics technology when it acquired Ageia in February. PhysX runs on the graphics processing unit, or GPU. Intel and Advanced Micro Devices, on the other hand, have been promoting technology that is executed on the central processing unit, or CPU. Intel's approach uses technology from Havok, a developer of a physics engine that Intel bought in September of 2007.

Adhering to the laws of physics
The goal of Nvidia's technology -- based on the laws of physics -- is to make game objects respond in a realistic way to physical events. More conventional technology uses a canned response, in which the same response is repeated over and over. For example, a window breaks, or a person falls the same way every time. In a PhysX-enabled football sports game, however, the angle and velocity of the impact is calculated by the GPU to generate a real-time response that is different every time.

The technology was meant to run on the GPU, according to Jon Peddie, whose firm tracks developments in the graphics chip industry. "It's a GPU thing, and the fact that EA and Take-Two are coming out (with support) gives you a clue why," Peddie said. "This really is a significant event," he said, "enabling the GPU to do physics."

Ujesh Desai, VP of product marketing at Nvidia, discusses physics strategy

(Credit: Brooke Crothers)

Ageia's secret sauce is its physics libraries, which are supported on Microsoft's Xbox, Sony's PlayStation 3, Nintendo's Wii, as well as on the CPU and Ageia's own PPU (physics processing unit), Ujesh Desai, vice president of product marketing at Nvidia, said in an interview last week. "It's a very open platform. Something game developers really liked, which is why a lot of game developers adopted it," he said.

The launch pad for Ageia on the PC is Nvidia's CUDA, or Compute Unified Device Architecture. CUDA already has a large installed base of GPUs that can run a C program, "which is what PhysX is," Desai said. "We bought Ageia, (and) they ported their PhysX API to our GPU, using our C compiler on top of CUDA. So now there are 100 million GeForce (chips) out there that can do PhysX processing."

And PhysX-enabled games will offer much greater realism. "Today, the way they do sports games is motion capture. They capture the different animation--running, falling," Desai said. "What you realize is that for the first 5 to 10 minutes of the game (or movie), it looks believable, but after you play for a while, you realize, wait a minute, every time he falls, he falls the same way. Every time I make that tackle, it looks the same."

The game Backbreaker uses PhysX. "They're calculating those tackles in real time, based on how the body interacts and the body mechanics interact. So no two tackles are the same," according to Desai. Another game, Mirror's Edge, is coming out in January from a company called Dice. The PC version will have PhysX in it, according to Desai.

"Ageia changed the rules on this," Peddie said. "It's much, much more realistic."

Ageia's physics was originally done on an Ageia Physics Processing Unit, Peddie said. "This was the only way to make it work. But now this capability (software) has been ported to Nvidia GPUs, and this can be done on Nvidia silicon," he said.

Physics can also be used to make things look more photo-realistic. "In today's games, cloth and hair look very fake because you don't have the right physical properties," Desai said. But with PhysX, "all these things can be physically simulated."

Unreal Tournament 3, a la PhysX.

(Credit: Nvidia)

Havok--the company Intel acquired--was the first to introduce physics into games and bring out a physics library. Havok's physics has been run on the CPU in a time-scheduled way, Peddie said. "Because of that, there weren't many CPU resources to really do a great job on the physics," he said. "Nothing would really happen. What happened, at most, is that you would hit this thing (a window or a wall, for example), and it would apply a decal to indicate that there was some change in it. It's not very realistic."

AMD, for its part, will pursue a balanced platform. "The GPU is a great place to do processing. We'll do the offloading (to the GPU), where it makes sense," said Korhan Erenben, product marketing manager at AMD Graphics Products Group. "(But) we are aligned with Havok, in terms of working on a future direction of physics. Right now, it is on the CPU, and we think that serves the broad installed base. Taking it to the next step would be to have a capability on the GPU--where and when it makes sense."

Physics is better on GPUs
Peddie explained why physics is more suited for the GPU than the CPU. GPUs today typically have hundreds of processors that are good at doing many things in parallel. "If you have threads or processes that can be run simultaneously, (and) if you have processors available to deal with each one of those threads, then you can get your results a lot sooner," he said.

He described a technique called Same Instruction Multiple Data (SIMD). "The same instruction is the physics equation. Things fall toward Earth all the time. And the multiple data will be what the things are. It might be a rock, might be a person, might be the wheel of a car. You have to be able to process this stuff and have it behave in a realistic fashion. To do that, you have to process it very quickly," Peddie said. "The advantage that GPUs bring is that they have this humongous number of processors. Certainly as good as the (Intel) 486 ever was. So they're really good processors, and you've got hundreds of them literally inside the GPU."

There will be challenges for users, however. "The tricky part is, why would I want to take one graphics card and spend $500 on it, and then not use it for graphics but rather use it for physics?" he said. "The answer is, of course, I wouldn't."

Peddie suggested that a gamer might use the really good card for physics and employ the old card "that you got last year" for graphics, assuming that there are enough slots in the PC.

AMD will work with game giant Havok to tailor Havok's game technology to AMD processors, the companies said Thursday.

The plans call for optimizing game-physics effects utilizing AMD's multicore processors and graphics processing units, or GPUs.

Game physics brings the laws of physics--or physical-world simulation--to a game. For example, explosions may be modeled differently depending on the terrain.

Havok, which Intel acquired in September of last year, provides development tools and services used by digital-media creators. Havok's technology has been used in game titles such as BioShock, Stranglehold, Halo 2, Half Life 2, and has been used to create special effects in movies such as The Matrix and Charlie and the Chocolate Factory.

Physics code has traditionally run on a CPU such as an AMD Phenom X4 quad-core processor. As part of the collaboration, Havok and AMD plan to further optimize Havok physics on AMD CPUs. Right now about 300 titles are optimized for Havok physics on the CPU, said Matt Skynner, vice president of marketing at AMD's Graphics Products Group.

AMD wants to take this CPU-centric approach a step further, however, and optimize certain components on the GPU, as well. "The plan is to work with them to leverage the right pieces of the physics (technology) that can be accelerated on the GPU," Skynner said.

"The feedback that we consistently receive from leading game developers is that core game play simulation should be performed on CPU cores," said David O'Meara, managing director of Havok in a statement. "Beyond core simulation, however, the capabilities of massively parallel (GPU) products offer technical possibilities for computing certain types of simulation," he said.

AMD is chasing Nvidia, which acquired Ageia Technologies in February. Ageia's PhysX software is widely used, with more than 140 PhysX-based games shipping or in development on Sony Playstation3, Microsoft XBOX 360, Nintendo Wii and gaming PCs, according to Nvidia.

And Nvidia has said that the conversion of Ageia's physics application interface to Nvidia's CUDA C language environment is under way. This means users will be able to get the benefits of a physics accelerator via a software download, Nvidia said.

The graphics processing unit (GPU) is in, the central processing unit (CPU) is out. That was one of the main themes running through the Nvidia fourth-quarter conference call earlier this week. Nvidia is the largest graphics chip supplier.

Gateway P series FX PC with Geforce 8800 GPU

(Credit: Nvidia, Gateway Computer)

During the call on Wednesday, Jen-Hsun Huang, President and CEO of Nvidia, repeated one thing often: GPUs are playing more of a central role in PCs, CPUs less so. "The CPU has become fast enough for the vast majority of (PC) users," he said. "PC enthusiasts, gamers, and design professionals have know this for some time." The GPU offers more horsepower for parallel processing, essential for today's visually rich environments, he said.

Huang cited the Gateway P series notebooks as an example. One model has an Intel 1.6 GHz processor and a GeForce 8800 GPU. He said systems like this with a "higher-end GPU" and "lower-end CPU" are better optimized for today's users. "Relative to a notebook with a higher-end CPU and lower-end GPU, the Gateway FX is twice the performance and yet $200 lower cost." In short, Huang was saying that users can save $200 by buying a system with a low-performance CPU and high-performance GPU--and get better performance to boot than the other way around.

Intel, of course, has other ideas. "We feel that the CPU is absolutely vital and you need a fast CPU and a fast GPU for the best experience. Take game AI (artificial intelligence) and physics for example, something that is consuming more and more CPU cycles," an Intel spokesperson said. "Also, the CPU is essential for intensive stuff like hi def video encode, 3D rendering," the spokesperson said.

Huang had a lot to say about physics too in the wake of Nvidia's purchase of Ageia Technologies this week (first announced on February 4th). Ageia's PhysX software is used with more than 140 PhysX-based games on the Sony Playstation 3, Microsoft XBOX 360, Nintendo Wii, and gaming PCs. (Game physics simulate the laws of physics in games.) "We're going to port the Ageia PhysX engine onto CUDA."

CUDA, a programming interface, has now shipped into 50 million GeForce 8 series processors and over the next several years will ship into a few hundred million more, Huang said. "Our expectation is that this will encourage users to buy a second GPU...and for the highest-end gamers, will encourage them to buy three GPUs." One GPU would be used for physics, while two for graphics (or vice-versa), Huang said. "Every single GPU that is CUDA enabled will be able to run the PhysX engine when it comes. In the end, it's just going to be a software download," Huang added.

But Nvidia's CEO returned to his overarching theme again and again. More Nvidia and less Intel. "Rebalance the system so that more GPU horsepower can be dedicated to the (user) experience." Nvidia even has a name for this strategy. The "optimized PC design approach." And Nvidia believes that more and more consumers are coming to know this, resulting in high growth. "The consumption of GPUs is increasing," Huang said, citing 80 percent year-to-year growth in Nvidia's discrete GPU business in the fourth quarter.

"I think I would say that [Huang's argument] has qualified merit. It's completely true that in some applications graphics, rather than CPU, is the limiting factor, and naturally Nvidia would be concerned with those applications most often," said Dean McCarron, founder and Principal of Mercury Research. But Intel and AMD are not standing still. "As far as rebalancing, it's pretty clear the CPU suppliers are actively re-partitioning their products, and graphics capabilities are perhaps the highest priority here. If you look at AMD and Fusion, or Intel and its Nehalem CPUs, both suppliers clearly see advantages to repartioning the PC around graphics -- in this case, moving graphics onto the CPU."

Nvidia's execution is not flawless. It is not competitive in the business segment and at the lower end of desktop and notebook lineups. Large computer segments unto themselves. Here both AMD-ATI graphics and Intel integrated graphics dominate. AMD-ATI is also competitive in the mid-range to high-end.

In related news, Nvidia's shares fell Thursday due to lower gross margins. On Wednesday, the company said that for the first time in 13 quarters non-GAAP gross margins did not increase quarter to quarter. Gross margin shrank to 45.9 percent in the fourth quarter from 46.4 percent in the previous period. In the fourth quarter, the company posted a 58 percent jump in fiscal fourth-quarter net income.

On another front, Nvidia CFO, Marvin D. Burkett, said no new process technology will be needed for the 8800 processors and they will continue to be made on a 90-nanometer process.