Laser Graffiti
Point a projector and a webcam at a wall, draw with a laser pointer, and the projector paints your strokes. Open source, runs in the browser.
In plain words
Laser Graffiti is an open-source browser-based application that lets users draw on walls using a laser pointer and projector. A webcam detects the laser movements, and the projector displays the strokes with visual effects like glowing neon or dripping ink. It works without a projector too, using a mouse or finger instead. The tool is designed for creative projection mapping and interactive art installations.
written from the facts on this page · September 2026
From the sources
Point a projector and a webcam at any wall. Draw with a laser pointer. The projector paints your strokes — glowing neon, dripping ink, spinning in 3D. Inspired by this video — laser tagging buildings with a projector, done years ago and still magical. Read the backstory ↓ No projector needed for this one — your mouse (or finger) is the laser. Pick a brush, flip on a mode, or play tic-tac-toe against the computer by drawing an X in a cell. Connect a projector as a second screen and point a webcam at the projected area. Open the control window and the projector window (press F for fullscreen). One click flashes markers into the corners of the projection; the camera finds them and computes the…from laser.consti.de
Pricing, as stated on its site
Free — Laser Graffiti is a free, open-source browser-based application. No pricing information is mentioned on the website.
checked September 2026 · prices change
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