Touch Overlays

I've used the next window overlays before and am about to buy another 40 inch this week for another project. There expensive but look great and work well.

i have been building touch screens in various capacities for a couple years now. honestly i have never worked with an overlay. some companies fly by night meaning they are here one day and gone the next so you need to make sure your ordering from reputable company that can deliver. the first thing i would do is check tuio.org and make sure there is some kind of tuio bridge existing for the technology you want to use. more than likely if there isn't a tuio bridge / client etc.. then no one is using the tech.

@jrs mentioned "nextWindow" which is a an overlay company that i have looked at in the past but have never gone with. particularly because they are a windows based api. there is a tuio bridge http://gkaindl.com/software/touchsmart-tuio which is based on a osx lib touche´ but the nextWindow its self needs a pc. seeing your asking about this on a quartz composer forum that you might want something more mac friendly ? just remember nextWindow does do multi-touch but the HP overlays are two touches only. to me multi-touch or the word multi requires at least three touches and not two. don't get me wrong people still use single touch screens.

ok so you have a few sources. the first is nuigroup the second being tuio.org. as far as overlays there are only a few people making them. nextWindow mentioned. then there is PQ labs. http://multi-touch-screen.com/ which are getting better and a bit pricy.

the only experience i have with overlays is from touch co. http://www.touchco.com/ this was a promising technology that came out of NYU. a printable conductive ink method for making touch capacitor systems. like i mentioned above some companies are fly by night. touch co no longer in business.

so your best bet would be to get a digitizer that fits your screen from http://www.stantum.com/en/. or make your own.

it is totally possible with just the TV to make your own system. i have built laser sytems, ftir, and di systems with televisions, and projectors etc... put it to you this way if you can get past taking your tv apart then you can build a touch system for under 100 dollars. you might even have a playstation camera already which is half the cost. most recently i have been going back to ftir systems which are a bit more expensive and or time consuming unless you get ribbon led tape which makes things very fast. either way you should be able to turn the tv's into a touch system for a couple hundred dollars rather than spend a few k on an overlay ?

The nextwindow systems work on osx fine - they just emulate a usb mouse so may even work on linux although I haven't tested this.

All of them do semi multi touch but this is unusable unless you really design your interface around the limitations. These are based on the way the system works - two cameras in the top corners of the screen - if one of your touches obscures the other from either of these cameras you have issues.

That being said they are the best looking overlay you will get as that size as they don't need to overlay anything over the screen (except glass). This makes the touch feel really nice unlike capacitive or other touch screen tech.

So in summery if you need multi touch look for a tuio system but if you just need single and/or need to use a screen then I'd go with next window