Personal R&D · Generative AI · Vibe coding

I wanted to wield a lightsaber in real life.

So I vibe-coded one.

A laser pointer becomes the blade in a multiplication game projected onto a wall. Aim with your whole arm, hit the answer, and make learning feel like play.

Watch the demo View the project on GitHub

Laser build Point. Aim. Solve.

The idea

The wall becomes the playground

Use an ordinary laser pointer to play a game on the wall.

The projector mirrors the game from the laptop. A phone or webcam watches the wall and finds the red dot. The laptop turns that position into an on-screen cursor, many times a second.

01LaptopRuns the game

02ProjectorThrows it onto the wall

03Laser + wallCreates the input

04CameraFinds the dot

Dot position becomes the cursor and feeds straight back into the game.

The setup

Four things I already owned.

The physical setup stayed deliberately simple. The interesting work happened in the connection between each device.

Phone and projector used in the Padawan Academy setup — The phone watches the projection while the projector displays the game.

Laptop running Padawan Academy beside a person holding the laser pointer — The laptop runs the game. The laser pointer becomes the blade.

Displays

Projector

Mirrors the laptop’s game onto the wall as the play surface.

Watches

Phone or webcam

Tracks exactly where the red dot lands.

Runs it

Laptop

Runs the game, camera tracking and calibration math.

The blade

Laser pointer

Its red dot becomes the tip of the lightsaber.

Calibration

The hard part

The game was easy. Calibration was the puzzle.

The camera sees much more than the projected game. It sees the whole wall and everything around it. I first had to teach the system where the projection starts and ends, then make the physical laser dot and digital cursor agree.

REC

1234 laser → cursor

1
Mark the four corners
I tap each corner of the projected image in the camera view. That boundary tells the system which part of the wall is the game screen.
2
Line up the dot and cursor
I map camera space to game space so the cursor appears in the same place where the laser lands. Getting that alignment right was ridiculously satisfying.

Why build it this way?

Make learning feel like play.

I work in learning design, and I wanted to make practice more immersive and playful for kids. Instead of sitting and tapping on a screen, they can stand up, move, aim and interact with the lesson.

The usual

Sit. Tap. Repeat.

The body stays still while the lesson happens on a small screen.

This experiment

Stand. Aim. Move.

The wall becomes the play space and multiplication happens in motion.

Bonus build The hand-tracking version.

No laser? Use your hands.

Pinch a number. Drag it into another. Release.

A second version uses MediaPipe to track one hand. The game asks, “What makes 24?” You pinch 4, drag it into 6, and watch 4 × 6 = 24 resolve.

4×6=24

You’re physically manipulating multiplication, not only looking at it.

What I love about this

An idea starts with “Wouldn’t it be cool if…?”

A few experiments later, you’re standing in front of a wall, playing with it. That is what I love about vibe coding: the distance between a daydream and a working thing keeps shrinking.

Explore Padawan Academy on GitHub