Such games used to be a simple matter of steering downhill and performing tricks as a wintry, 3D world of virtual pine trees and moguls inconsequentially whirred by.
Those games looked realistic, but the objects in them did not behave realistically. Because of the computing muscle needed to calculate all those snowflakes and their interactions, avalanches were pretty much out of the question.
"Stoked Rider," though merely a demonstration, is one of the first examples of how video games can benefit from a new breed of computer chips dedicated to calculating the physics of a game's virtual world.
Leading the effort is Mountain View, Calif.-based Ageia Technologies Inc. The company is the first to offer a specialized computer chip — called "PhysX" — designed to give video games a better sense of reality, as dictated by Newtonian physics.
"I've always been bugged that, with all the high-power technology, that the games aren't more realistic," said Manju Hedge, Ageia's co-founder, chairman and CEO. "Computers are very underpowered for a lot of things."
That's certainly true in video games, which tend to be one of the most demanding tasks for computers.
The idea behind PhysX is to take the strain of physics calculations away from the central microprocessor, freeing up all sorts of possibilities in video games.
The processor comes on a card that installs into a free slot inside a desktop computer running Windows. It's able to process hundreds of thousands of moving objects at the same time, its creators claim.
So what does this mean?
Imagine you're in an industrial warehouse packed with wood boxes, piles of lumber and oil drums. And you just so happen to have a grenade launcher at the ready.
In the real world, blasting these objects would have obvious, chaotic results: The boxes would splinter and burn, smoking logs might roll across the floor, and the spilled oil would roil and slosh around the ensuing mess.
Take this situation into the traditional video-game realm, and everything becomes static. The virtual boxes may burn and move around, but they would never break into splinters like they would in the real world. Same goes for the logs and the oil.
The reason? Limited computing resources.
Between the computer's main processor figuring out the artificial intelligence of the game and the video card displaying the graphics, there isn't enough leftover power to bother with the enormous amount of data crunching needed for more realism.
"It would always come at such a high performance cost, there was always a trade-off," said Jeremy Stieglitz, president of Artificial Studios in Gainesville, Fla., which is developing a game that takes advantage of the PhysX chip. "What PhysX does is really eliminate that trade-off."
The advent of such specialized chips mirrors the rise of dedicated 3D video cards in the mid-1990s.
Before PCs had 3D abilities, video games relied on software tricks to fool players into seeing a game with depth and perspective when it was actually two-dimensional. There wasn't enough processing power for real 3D.
That all changed when companies like the now-defunct 3dfx Interactive debuted specialized chips to quickly process 3D graphics.
When coupled with special software, popular PC games at the time such as the first-person shooter "Quake" were transformed into fluid, 3D worlds.
The industry never looked back. Today, 3D graphic chips are standard issue on PCs, laptops, even cell phones.
It remains unclear how many will buy into a product like PhysX.
PhysX does not work in laptops, nor is it compatible with game consoles such as Microsoft Corp.'s Xbox 360 and Sony Corp.'s upcoming PlayStation 3, which pack speedy multicore processors but lack physics acceleration at the hardware level.
Ageia's chips, which became available last month, come preinstalled on certain pricey, ultrapowerful PCs from Dell Inc., its wholly owned subsidiary Alienware Inc., and Falcon Northwest.
But these systems cater to a select group of hardcore gamers who are willing to spend $5,000 or more for a PC.
Two electronics manufacturers also sell standalone add-on cards for about $300.
Only the highest-end PCs need apply. PhysX requires a system with a speedy processor and graphics card — after all, all those extra bits of flying metal and glass still have to be drawn on the screen by the graphics card.
In fact, lower end systems may see a performance hit with PhysX.
Jupiter Research Vice President Michael Gartenberg said hardcore gamers who are already spending such large sums will be the first to snap up PhysX. Convincing other PC users could pose a challenge, however.
"Video games look pretty darn good as it is right now," he said.
So far, the chip is limited to mostly game demonstrations, with only two full-blown games available: the PC version of "Tom Clancy's Ghost Recon Advanced Warfighter" and "City of Villains."
An early version of the action shooter "CellFactor" is available to download as a demonstration but the final game isn't scheduled to be released commercially until sometime next year.
Hedge expects there to be 20 games using the chip by the end of the year.
At Cryptic Studios in Los Gatos, Calif., producer Serdar Copur said it took about four months to add the Ageia physics support to the multiplayer online role-playing game "City of Villains."
The result is a new level of villainy for players: newspaper racks can not only be tossed around, but when they smash into something, the contents fall out and swirl around. The wake left behind as you fly around at high speed actually pulls around bits of debris just like it would for real, assuming you could fly.
"Physics provides the ability for players to feel like they're seeing something new, they're doing something different," Copur said. "I can certainly see there being a huge market for this."