Dianne, I'm unclear about just one thing here -- which "special code" -- you mean the code in the sample apps?
Relative to the conversation since -- I don't disagree; this isn't an Android "bug" and it theoretically should be in the device driver. It does raise a question, though, about the API design. If handset makers are delivering data that doesn't work the way developers expect, and the hardware itself can't be "fixed" (which it most definitely can't), then the question is, how do you bridge the gap between what the API appears to provide and what's actually there? On the other sensors, we have the ability to set sensitivity and make appropriate resource consumption tradeoffs, as with the timing resolution of the accelerometer, for instance. Why not provide something in the API that allows corrected data - with the tradeoff in interpolation -- in case raw data is not accurate enough? For that matter, given the wild variability here, maybe there needs to be some sort of additional information provided about the device beyond just whether it provides for these second+ touch points. Peter On Feb 12, 2:42 pm, Dianne Hackborn <hack...@android.com> wrote: > Sorry I meant exactly what I said: this is how the touch screen hardware on > the Nexus One works (which is essentially the same screen as on the G1 and > myTouch). The Droid has a sensor from a different manufacturer, with > different behavior. Other phones will likewise have different sensors. > > This has nothing to do with the Android platform. Please do not file bugs > about it. Android is just reporting what the hardware is capable of > reporting. There is no "normalization" for games or such, there is just the > data the screen provides. (Though there is some special code in the current > framework for cleaning up the data from the Droid screen; arguably this > should be in the driver or firmware for it, since this is really screen and > hardware specific kind of stuff. At any rate, it is not applicable to basic > screen capabilities like here.) > > There is a good analysis of the G1 class touch screen here: > > http://lukehutch.wordpress.com/2009/01/10/full-working-multitouch-on-... > > On Fri, Feb 12, 2010 at 4:39 AM, Sean Hodges > <seanhodge...@googlemail.com>wrote: > > > > > > > I think what Dianne is saying is that the values you are seeing are > > what is raw data returned from the sensor, it's not normalised for > > multi-touch games, or for any particular purpose. > > > My understanding is that the values returned have different coordinate > > spaces, and have a tendency to "jump" about when used directly (I > > suspect this second issue is more an artefact of the device-specific > > screen sensitivity, dents, scratches and the impact of screen > > protectors). > > > Take a look at Luke Hutchison's multi-touch controller, it might > > provide a suitable wrapper for your requirements: > > >http://lukehutch.wordpress.com/2010/01/06/my-multi-touch-code-ported-... > > > On Fri, Feb 12, 2010 at 8:39 AM, Kevin Duffey <andjar...@gmail.com> wrote: > > > Ugh..sorry.. I hate using my moto droid to reply.. fat fingers and a > > > horrible physical keyboard don't go together. > > > Dianne, I don't understand your response.. it's quite clear from several > > > developers that the multi-touch has problems severe enough that > > > it's deterring game developers and others that would use it. You're > > saying > > > that it's normal behavior for the multi-touch to change the location of 2 > > > touches such that one of them is completely not in the location of where > > you > > > touched it? Is this an Android platform issue with how it handles sensor > > > data.. or are you saying that the G1, myTouch, Nexus One and Moto Droid > > (not > > > sure about others) ALL have built their touch sensors to purposely report > > > this sort of behavior when you touch, then release, then touch again as > > > Robert and several other posters have state is happening? > > > > On Thu, Feb 11, 2010 at 7:46 PM, Dianne Hackborn <hack...@android.com> > > > wrote: > > > >> On Thu, Feb 11, 2010 at 6:10 PM, Kevin Duffey <andjar...@gmail.com> > > wrote: > > > >>> So what I want to know is what is being done about this? Is there a > > bug > > >>> file and if so is it > > > >> This is how the sensor hardware works. It is essentially the same > > sensor > > >> as the G1 and myTouch. Please don't file a bug about it. > > >> -- > > >> Dianne Hackborn > > >> Android framework engineer > > >> hack...@android.com > > > >> Note: please don't send private questions to me, as I don't have time to > > >> provide private support, and so won't reply to such e-mails. All such > > >> questions should be posted on public forums, where I and others can see > > and > > >> answer them. > > > >> -- > > >> You received this message because you are subscribed to the Google > > >> Groups "Android Developers" group. > > >> To post to this group, send email to > > android-developers@googlegroups.com > > >> To unsubscribe from this group, send email to > > >> android-developers+unsubscr...@googlegroups.com<android-developers%2Bunsubs > > >> cr...@googlegroups.com> > > >> For more options, visit this group at > > >>http://groups.google.com/group/android-developers?hl=en > > > > -- > > > You received this message because you are subscribed to the Google > > > Groups "Android Developers" group. > > > To post to this group, send email to android-developers@googlegroups.com > > > To unsubscribe from this group, send email to > > > android-developers+unsubscr...@googlegroups.com<android-developers%2Bunsubs > > > cr...@googlegroups.com> > > > For more options, visit this group at > > >http://groups.google.com/group/android-developers?hl=en > > > -- > > You received this message because you are subscribed to the Google > > Groups "Android Developers" group. > > To post to this group, send email to android-developers@googlegroups.com > > To unsubscribe from this group, send email to > > android-developers+unsubscr...@googlegroups.com<android-developers%2Bunsubs > > cr...@googlegroups.com> > > For more options, visit this group at > >http://groups.google.com/group/android-developers?hl=en > > -- > Dianne Hackborn > Android framework engineer > hack...@android.com > > Note: please don't send private questions to me, as I don't have time to > provide private support, and so won't reply to such e-mails. All such > questions should be posted on public forums, where I and others can see and > answer them. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
