First things first: I put the blog back up. Whoopee! Whether I’ll do much with it remains to be seen but it’s useful for sharing things that don’t fit nicely into Facebook’s content model.
So a couple weeks ago I ran across a video from Matt Parker that I had seen before:
Actually the video I ran across was a follow up to this one, but this one gives you the context better. Reader’s Digest version: Matt hooked 500 addressable LEDs to a Raspberry Pi and wrapped them around his Christmas tree. Given that set up he could set the color of an LED based on its linear address (e.g. “Make the 337th LED in the strand bright pink”) but not by its location in 3D space. But by lighting up the LEDs one by one, taking a picture from multiple angles, and doing some image processing, he could create a map of where all 500 LEDs were in 3D space. Using that he could then create special effects like lighting up a plane of color as it sweeps across the tree.
I wanted to do the same thing, except I didn’t want to buy 500 LEDs and a Christmas tree without knowing if the project was within my technical skills and would sustain my attention span. So I bought a strand of 50 LEDs and wrapped them around an Easter basket.
What you’re looking at is red, green, and blue bands sweeping across the basket, first in the X direction (left to right), then in the Y (back to front), then in the Z(top to bottom). It’s far from perfect; the way I did the scanning certainly introduced some error and even at this scale 50 pixels is hella lo-res. But it’s a start.
Now I just need to figure up how to scale it up without burning down my house.
