NeoPixel Stick Diffuser

This thing was inspired by user Protowerkstatt, thing 2783648, NeoPixel Bargraph. I redrew the design from scratch and added cylinders to shape the light emitted from each LED.

This is for NeoPixel sticks (8 pixels/LEDs per stick) from Adafruit. It has a raised, hollow cylinder that can diffuse light in two ways, altering the shape and appearance of the light:

* Mounted with the NeoPixel elements directly over the cylinders, the shape is round
* With the stick mounted in the other direction (LEDs not directly over the cylinders), the shape is more oblong and fuzzy, giving a kind of bubble effect

To test, use the Arduino Adafruit NeoPixel library example, strandtest:
* set number of LEDs to 8
* comment out the function calls except for TheaterChase
* blue seemed to be the nicest effect to resemble bubbles
* change time in the function call (main loop) to 110 from 50

There are cut-outs at each end of the diffuser for wires, so it's easily chain-able, to add more unit