Who would have thought that something as ordinary as the surface of some water being used as more than a poor substitute for a mirror? Just take a look at this Water Touch Screen video and you'll know what we're talking about. It relies on a webcam as well as a cleverly written piece of software to turn the water's surface into an unorthodox way of playing out a touchscreen interface. It does so using some pixie dust and plenty of magic - we jest, the webcam will snap a photo of the surface of the water from the lower side, and only when the finger has invaded the water. Following that, a color tracking system on Max/MSP+Jitter finds coordinates where the finger appears while producing a cursor move and click in return. Any image distortion will be adjusted by affine transformation. Pretty neat, eh?
