The Case for PC 3D Gaming

If this week's press launch for the Nintendo 3DS didn't demonstrate it spectacularly enough, the future of gaming has three dimensions. But while the Mario-makers' handheld is a great example of a gaming experience built for 3D from the ground up, elsewhere console 3D remains a compromised experience: few titles support the format, and resolution, frame-rate or both can be impacted in the transition from 2D to 3D.

So how about a gaming format that supports over 500 games in 3D for an alternative? A system that can run, say, Call of Duty: Black Ops in full 1080p with graphics settings that outstrip the PS3 and Xbox 360 versions, at the full 60 frames per second, and in 3D? Welcome to the world of NVIDIA 3D Vision.

Released in 2008, 3D Vision uses active shutter glasses in combination with a high-frequency CRT monitorm projector or, more popularly, a 120Hz LCD display. AMD - NVIDIA's GPU competitor - has its own 3D implementation, but it is fair to say that 3D Vision has much of a grip on the PC market.

"3D glasses and technologies have come and gone in our industry many times, but they never succeeded because companies were not heavily investing in all aspects of the business," NVIDIA product manager Andrew Fear tells Digital Foundry. "Our goal with 3D Vision was to transition the 3D industry to use LCD desktop monitors and create flicker-free, full-resolution 3D in a product that out of the box worked flawlessly. We also work closely with game developers and other content providers to help ensure that new titles are optimised to give consumers the best possible 3D gaming experience."

Monitors, just like other forms of technology, are always getting better as their manufacturers improve their methods, and transitioning from the traditional 60Hz to 120Hz and beyond is one way in which display tech is evolving. NVIDIA was proactive in promoting these displays, and saw the potential in them for full frame-rate stereoscopic 3D.

"Monitor manufacturers are always interested in increasing the LCD response time and grey-to-grey response time," Fear explains. "However, for a lot of users the benefits of 120Hz refresh rate are immediately noticeable in their gaming and so they may not value the [3D] feature as much. By combining it with 3D though, you can create an instantaneous experience which is like nothing you've ever had before."

Many games support the faster refresh rate, but 3D Vision opens up a way to stereoscopically exploit the new tech too, so 120Hz is a bit of a win-win for NVIDIA, because to get the most out of both, a graphics card upgrade is the way forward.

In putting together this feature, we've played many key games traditionally associated with PS3 and Xbox 360 on our 3D Vision setup, based around a 23-inch ASUS VG236H 120Hz display. We've enjoyed Battlefield: Bad Company 2 at close to maximum settings at 120FPS and we've played Call of Duty: Black Ops at 1080p60 with 16x MSAA (!) and barely a hiccup in performance using our monstrously powerful GTX 480/Core i7 setup. These are console games radically transformed: they look better, they feel better to play, and they're getting us involved in the action in a way the console versions just can't match. This feels like the future of 3D. It feels like the way it's supposed to be.

In this "compromise-free" 3D environment, the PC version of Black Ops knocks the spots off the disappointing experience we had with the console versions running in stereoscopic mode - as you might expect, bearing in mind the almost brutal levels of power our PC gaming rig brings to the table. The good news is that with the way things are going you will not need to spend a colossal amount of money to produce a first-class experience: consumer-level 3DTVs mean you won't require a 3D Vision-specific monitor, and the graphics card requirement for a top-end experience on this tech is much lower too, as we'll discuss later.

PC graphics tech inherently has the raw power to blitz 2005-vintage console performance, but is the quality of the 3D itself comparable? When we first looked at Sony's stereoscopic solution, the engineering team was at pains to point out that its solution gave full control of the 3D experience to the developers, for example in the crucial positioning of the two cameras. It's well known that NVIDIA 3D Vision operates at the driver level, so is the 3D experience constrained by "one size fits all" limitations, or can game-makers bring their own creativity into the mix?

The answer appears to be that both implementations are supported by NVIDIA, but the theory that the driver is patching vertices to produce the 3D effect is apparently unfounded, or is at least just part of the story.

"3D is a combination of GPU hardware and software. Native inside our driver we have a system that creates two virtual cameras from any DirectX-based application. We analyse every frame and create a distinct left eye and right eye view," explains Andrew Fear.

"Our GPU then renders each scene twice and creates the 3D world. We are not trying to patch vertices or do edge-detection for 3D, which results in sub-optimal 3D quality, usually causing the world to look flat. On a high level, we can automatically convert any application into 3D. Beyond that, we offer game developer access to APIs which let them control convergence, depth, camera position, and more, and it works very much like the PS3 system."