Tim Dobson wrote: > I recently came across this blog post which, interesting explains that the > Android G1 is *capable* of multitouch but chose not to use it for some > reason - some suggest, for fear of litigation from Apple. > > http://osswatch.jiscinvolve.org/2009/01/30/what-does-that-two-finger-gesture-mean/ > > I don't live in the USA so it may not be such an issue for me but it could > still cause problems for Openmoko... > > What are your thoughts?
I don't think this will cause trouble for openmoko - for the neo phone screen doesn't support multitouch. It doesn't matter what the software might be able to do with a multitouch-screen, when it isn't available. To get in patent trouble, you actually have to infringe on the patent in question. Most touchscreens can't do multitouch, and new screens likely won't have it either because manufacturers will worry about that patent. Some screens, such as the neo, can do "fake multitouch": If you touch with two fingers, the screen first notices the location of the first finger. When the second finger lands, the screen notices a new location, somewhere between the two fingers. The location of the second finger is never seen, unless the first finger is released. So when two touches happens with no release inbetween, it could be a drag. If the jump distance is too long for a regular drag, then assume a second finger landed somewhere further out along the line between first and second touch. The location of the second finger will not be very precise, for the screen doesn't necessarily register the exact midpoint between the fingers. The midpoint will be closer to the bigger finger or the finger that is pressing hardest. This is a problem, for the second finger will necessarily touch lightly with a small area in the beginning. So the movement of the "weighted average" position may resemble a drag. Perhaps some careful study of such drags and two-finger touchdowns will reveal systematic differences so the software can be written that usually gets this right. Some averaging and a screen with good bandwith *may* be able to get a reasonable position for the second finger in reasonable time. But then apple might get irritated. Also, it might be hard to see the difference between a two-finger touch and tapping two places in rapid succession - unless you can be sure you always get a release event. Helge Hafting _______________________________________________ Openmoko community mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/community
