3D games will no doubt accelerate the adoption of 3DTVs, provided it’s financially viable for 3D TV manufacturers to incorporate the extra dimension on their mid-range sets. But for 3D gaming to become prevalent, Microsoft and Sony need to launch their respective next-generation game consoles as soon as possible, even though both the Microsoft Xbox 360 and the Sony Playstation 3 (PS3) can currently render games in Single-Frame stereoscopic 3D (SS3D).
In the coming days, Sony will release a firmware update which will equip the PS3’s HDMI port with a selection of protocols native to the v1.4 specifications, allowing the PS3 to fully support up to 120p (60p per eye) Frame-Sequential SS3D. However, the majority of 3D games will initially be restricted to simple arcade games due to present-day limitations in hardware resources. For games such as KillZone to be rendered in 3D, in-game graphics or resolution must be sacrificed to maintain 30 fps per eye (total of 60 fps). Here’s why.
The majority of games on the Sony PS3 are rendered in 720p30, which translates into 27,648,000 (1280 x 720 x 30) pixels per second (on average). Forcing the Sony PS3 to deliver double the frame rate (for both eyes) for 720p Frame-Sequential SS3D is not possible without reducing graphics quality/ resolution. In addition, the Sony PS3 lacks true hardware-accelerated vertical scaling, so rendering 3D games in frame-sequential 540p (960 x 540) could pose a problem, unless 3D game developers resort to utilising the Sony PS3’s Cell microprocessor for vertical scaling, which may in turn impair the game’s performance.
Even for Single-Frame SS3D, the required pixel output remains stupendously high (62,208,000 PPS for 1080p30). And because the game has to natively support 720p in both 3D and 2D, the longer development time adds significantly to the cost.
Despite Sony’s marketing claims, the PS3 is not an all-conquering hardware powerhouse, and its internal architecture offers limited flexibility for 3D game developers. To increase pixel rate, the PS3’s GPU (Graphics Processing Unit) has to be freed by reallocating a number of processing tasks to the Cell, which is not easy to accomplish. And although the Cell is quite capable of rendering vector graphics, it is not a replacement for the RSX GPU.
In theory, what game developers can do is to cut the horizontal resolution of 720p (1280) to 640 (640 x 720 x 30p x 2 = 27,648,000). Since the image is horizontally compressed (anamorphic), developers can use the horizontal hardware scaler to scale 640 to 1280 (via an integer) without round-off errors. The image may contain artefacts, but it ultimately benefits both players and developers.
In any case, it will be interesting to see how 3D game developers can maximise performance while maintaining certain visual quality/standard.
As for the Microsoft Xbox 360, it is not possible to update its HDMI controller to enable Frame-Sequential SS3D. However, Microsoft has hinted at the possibility of Xbox 3 (X3) with native 3D support, which is not surprising considering that Project Natal and 3D go hand in hand.
On the computer front, PC gamers will benefit from 3D TVs as both ATI and NVIDIA support Frame-Sequential SS3D, but the halving of frame rate per eye can pose a problem if the hardware cannot maintain an average of 60 fps. There is also the issue of headache and nausea caused by 3D due to active viewing (as opposed to passive viewing).
3D gaming is touted as the main driver for 3D TV take-up, and rightly so since 3D games bring us one step closer to interactive virtual reality. But for the benefits of 3D gaming to be fully realised, a breakthrough in hardware limitation is needed, which is why Microsoft’s and Sony’s next-gen game consoles can’t come soon enough.
