Playing with multitouch (includes source code)

[Mizonnz]

I've always found one of the most interesting and underused features of the iphone is it's multitouch screen. As multitouch is still fairly new most people are still coming to grips with what can be done with it. Pinch to zoom is being used more now, as is two finger rotate, but what more can we do with this new medium?

I was watching a video of Jeff Han from 2006 YouTube - Multi-touch screen by Jefferson Y.Han for some inspiration and there is an interesting game being played there for a few seconds (at about 2:46) using multitouch to make a slingshot, so figured I could make something similar on the iphone (although using more of a bow and arrow). A few hours of mucking about and I had something kinda cool but maybe a little useless as the iphone screen is really a bit small, so I decided to comment the code more and post it here for everyone to look at and use bits or get inspiration from it.

RapidShare: 1-CLICK Web hosting - Easy Filehosting

This demo requires touching the screen in 3 places. The first 2 touches define a bow while the third provides the arrow. Letting go of the arrow will fire it. There's code in there for tracking individual touches (using previousLocationInView) and some quartz drawing routines (probably not the best way to draw this stuff but interesting to look at anyway). Hopefully some of you guys can learn more from looking through the code, I'd be interested to see what you can do with multitouch.

Perhaps a game could be made from this but really the iphone screen gets too full once 3 fingers are on there. Maybe it would work better on the iPad's larger screen, but I don't intend on getting one of those just yet.

[BillyGiggles]

when i downloaded the source code all it was was a black screen on the simulator

[Mizonnz]

Originally Posted by BillyGiggles

when i downloaded the source code all it was was a black screen on the simulator

The simulator isn't multitouch - you need to touch in at least 2 (better yet 3) places at once for something to happen. Try it on an actual device (iphone, ipad, ipod touch).

On second thoughts maybe it'll work in the simulator with the touchpad on a macbook, but I'm using an imac so I dunno.

[BillyGiggles]

oh k so what does it do?

[Mizonnz]

It makes a bow and arrow, you can even fire the arrow. The bow runs between two of your fingers, and a third finger draws back the arrow. Makes more sense you you see it running.

The idea of the program is to get developers thinking about what they can do with multitouch, most apps don't use it or maybe use pinch zoom, but there's alot more that can be done if we have the imagination to create it.