Back in November, I wrote about the discovery that while Multi-touch wasn’t available on the HTC Dream (aka the T-Mobile G1), the Synaptics screen had the capabilities for two-fingered gestures. This was discovered by developer Ryan Gardner, who found that the kernal driver had lines commented out that watched for the second input. His methods were simple, though it required a recompile, and a flurry of rumors started as to why multi-touch was disabled if the G1 had screens to support it. HTC and Google stayed out of it, with only HTC stepping up once to say that the G1 was only ever meant to be a single touch device.
However, the Android community wouldn’t take no for an answer, and today we have working evidence that should bring more light into what the G1 can do in terms of Multi-touch, and why it will never be supported, on the G1 at least.

Android Developer Luke Hutch has managed to activate multi-touch without having to recompile the kernal, and only rewriting one classfile. He has a video demonstrating his application, and explains the current limitations of mulititouch.
Luke says that the Synaptics screen is not a true 2D touchscreen, but rather a 2×1D, which basically means that it’s hella responsive for single input, but would cause overlapping touchvalues when fingers cross the x or y axis. He does show that gestures like swipe and pinch would work, but rotation and other complex gestures would not be possible on the current hardware.
What does this mean?
Nothing. Unless the Android Source team decides to support this (read: NO), it will never make it on the G1. It would also be foolish for developers to write gesture only applications at this time, seeing that the only people to benefit are developers themselves. This is not an end-user solution, and though the community is still looking for official multi-touch on the G1, the answer today is still “well, yes.. but no.”
You can check out his very detailed explaination, as well as download the sourcecode for free at his site: http://lukehutch.wordpress.com/android-stuff/
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