N810 Multitouch F-F-F-Fun

I'm back from vacation, summer went fast as always! Tried to stay away from computers, spending the time with family & friends and enjoying the weather while it lasts... But I did have little coding fun also, testing how well "multitouch" would work in N810 ;-)

Here comes video:



Update: Like all respected magicians, I'll show how this trick works for the ones who didn't already know the behavior of (resistive, single-touch) touchscreens under multiple touches. As thp first commented, it is "using the 'merged' blob position that you get with the single touch screen and interpreting it as the middle of two or more equal-pressure points".

Now here is a video showing the same demo in PC, with "cheat mode" turned on:


So it's mostly useless... but somewhat f-f-f-fun :)

Comments

thp said…
I suppose this is just using the "merged" blob position that you get with the single touch screen and interpreting it as the middle of two or more equal-pressure points, or is there more to this?
July 27, 2009 at 4:00 PM
Kaitsu @ QUIt Coding said…
thp: Yes, only tricky part is building "touch grid" so that it actually feels like working all the time, here with 3 touch points. Usable enough for some specific games etc. but waiting for real multitouch devices(s) and support in Qt!

http://labs.trolltech.com/blogs/2009/04/20/multi-touch-support-in-qt/
July 27, 2009 at 5:44 PM
Martin Grimme said…
Multitouch "simulation" on a resistive touch screen is not very precise as the amount of pressure on each pressure point has an impact on the reported position.

But watching your video gives me the idea that this technique would still be useful for bringing joypad controls on screen. Great work!
July 27, 2009 at 7:21 PM
turn.self.off said…
hmm, joypad controls.

if that really worked, those emulators would be a whole lot more interesting.
July 27, 2009 at 10:48 PM
Anonymous said…
that looks really good.
there has already been multitouch available on n810 for a long time.
http://www.youtube.com/watch?v=dJWvvn_cePM
July 27, 2009 at 11:35 PM
Kaitsu @ QUIt Coding said…
These joypad discussions remind me about "analogpad" http://kgronholm.blogspot.com/2008/12/happy-new-year.html

Not sure how usable that would be with real (action) games, but should be doable anyways =)
July 27, 2009 at 11:47 PM
Kaitsu @ QUIt Coding said…
Anonymous: Ah I have missed that, thanks for the link! Damn liquid/lcuk, he makes us average hackers look so... average ;-)
July 27, 2009 at 11:57 PM
lcuk said…
Kaitsu, you are anything but average, i like seeing the stuff you are playing with in qt :)

I'm guessing for now if you press in the centre of all the dots they light up

your analogpad is already multitouch friendly isnt it? i mean, it can do diagonal presses like a real gamepad and pressing left+right together would cancel themselves out.

btw anonymous, that video does not do justice with what i want multitouch for ;)

happy hacking!

gary
July 28, 2009 at 12:56 AM
Anonymous said…
This looks pretty neat, but I imagine (as lcuk pointed out) that this demo worked as well as it did due to the geometry of the touch-points? Even so, pretty cool.
@liquid/lcuk "that video does not do justice with what i want multitouch for ;)":
Are you teasing us, or did you mention something about that elsewhere already? Your liqbase demos are enough to make me drool, but concrete information is lacking...
July 28, 2009 at 7:37 AM
Kaitsu @ QUIt Coding said…
liquid & ffejery: Thanks! Yes, that's the way demo works, updated post now to show video with "cheat mode" on. So liquid, what's the status with liqbase, haven't seen you blogging about it lately...? =)
July 28, 2009 at 9:28 AM
Tim Samoff said…
Far from average (as Gary says)... This is so cool to see. The possibilities are endless -- even with the input being less than accurate. Exciting! :)
July 28, 2009 at 2:47 PM
lcuk said…
Heh,
I've been busy with a few little things.
you just haven't been looking in the right places :P


couple of snapshots, not ready just yet and there is much more besides.

quite happy with my coding, making use of things I have developed.

http://liqbase.net/liqbase_net_preview.png
http://liqbase.net/liq.20090728_013953.liqbase_net.scr.png

the graffiti wall is now completely merged and has the ability to view sketches/photos/calendar entries (and other things) in the nice wall.

the database I created (over 100mb on device) contains every single sketch/photo/screenshot ever taken and includes full tagging and grouping capabilities. its being hammered into proper shape atm and proper sync is coming (its one way at the moment)

all in all its goin well :)
July 28, 2009 at 7:12 PM
Kaitsu @ QUIt Coding said…
Tim Samoff: Thanks! I'll wait for real multitouch support into Qt and suitable device(s), then provide r-e-a-l-l-y cool UI's utilizing them. Promise ;-)

liquid: Sounds (and looks) nice! Didn't know you have browser backend in there also, cool! =)
July 28, 2009 at 8:48 PM
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