DeskSaver is an application for the fluid desk. Like a traditional screensaver, the program gets started upon an idle-timeout, running until any kind of user input event occurs. Once activated, it simulates raindrops falling on a water surface, where waves caused by the raindrops seem to reflect off real objects lying on the table.
This is achieved by taking a picture of the whole table, using the digital camera mounted on the ceiling, and then performing edge detection to find contours of objects. Filling out detected contours, the Desksaver can determine exactly which pixels on the projected image are covered by objects, and make water waves reflect from them.