Wacom light graffiti
posted Sep 20th 2009 2:14pm by Mike Szczysfiled under: laser hacks, misc hacks
[Jon] wanted to have some fun with the Graffiti Research Lab’s LASER Tag. Unfortunately his computer wasn’t quite up for the challenge of detecting the laser pointer with a webcam. Not to be discouraged by this hardware limitation, he purchased a used Wacom tablet and threw together some code to make it work with the GRL display software. Now designs can be scrawled on the pad and the projector displays them with the familiar dripping paint effect.
Hey there! Just to avoid some confusion — I’m not actually using the GRL software at all in this project. I believe GRL’s program uses Quicktime, which crawled on my machine.
My software (which is a really small program) simply reads input from the Wacom via a serial port, and uses libSDL to draw on the screen. The dripping effect is done by randomly selecting some points in the user’s stylus stroke to “drip.” The “drips” are kept track of and are updated (i.e. redrawn a few pixels down) after some amount of time.