Hidden feature turns iPhone into TV gaming device

By Katie Marsal

With a little work and the help of an undocumented feature in Apple's iPhone Software Developers Kit, one iPhone developer was able to turn its game into a version suited for playback on big-screen TVs.

After discovering the hidden MPTVOutWindow class in the iPhone SDK last month, ArsTechnica's Erica Sadun got in touch with Freeverse, makers of Moto Chaser, and encouraged them to experiment with the APIs. A few hours later, the TV version of the iPhone game was born (video below).

Though largely demonstrative, the game uses the iPhone's accelerometer for input and steering while routing the game's video through a video-out cable to the TV. Freeverse noted that the program ran best on the second-generation iPod touch, which includes a 532MHz processor compared to the iPhone and iPhone 3G's 412MHz chip.

Even so, Moto Chaser maxed out at around 20 frames per second, making it "nearly playable," according Freeverse, whose producer Bruce Morrison noted that the "norm for commercial games is 30fps, a point at which motion becomes as smooth and watchable as normal TV video." Sound quality, however, was said to be greatly improved when pumped through a respectable sound system.

"When Morrison approached senior programmer Mark Levin, he had basically one set of instructions. 'Make it work before lunch.'," Ars reported. "Freeverse had very little time to allocate to putting together the demo. In the end, the entire development effort took about three hours."

Obviously one could imagine the possibilities of faster iPhones paired wirelessly with Apple TV to serve as a video game controller. In the meantime, you can read more about Apple's plan to muscle advanced gaming graphics into iPhones.

Original here