The software requirements for the visual system at Halcyon in San Francisco were straightforward. It needed to control nine HD projectors as well as the club lighting system. More interesting was the process of pixel mapping the 20 universes of individually addressable LEDs.
Mapping LEDs is a common task. Typically people create a structure, cover it with individually addressable LEDs and then want to be able to apply a video or image to that structure.
The mapping approach used at Halcyon was very similar to how texture mapping works in 3D animation and is depicted in the first featured image. It went like this:
- - Create a 3D model of the LED structure where every vertex represents an LED
- - Unwrap the model and UV map it
- - Apply a texture to the UV mapped model
- - Sample the color at each vertex and set each LED to the sampled value
In this way anyone can pre-visualize how content is going to appear on the structure in real time.
The featured video shows the final installation before the nightclub opened. There are more examples online.
The code for a somewhat simplified version of this project is available here.