So far in the project this has just been circle-lamp for lack of better name. However disk lamp is more appropriate really.

### Layout

This started with me seeing a big disc somewhere and thinking it would be cool to build a lamp that is a disc with a matrix of RGB-LEDs stuck on.

So I still had not one but TWO 5m WS2812b (neopixel) in store, that’s 300 LEDs. Their pitch is around 28mm so step one was to calculate how big a circular lamp I can make with that. The idea was to save a lot of soldering by just sticking the LED strips in parrallel. If the distance between strips is the same as the pitch between LEDs it will make a perfect matrix.

I recently realised that Processing is actually a great tool for doing graphical calculations and arrangements like this. I did the calculation first but I really wanted to see in each case which LEDs will be in and out of the circle and what the final outline would be, and to compare the difference of one LED in the center to half an offset, i.e. odd and even number of LEDs.

While working on the animations however I found I much prefered a triangular grid with every second row offset a little. Here as equilateral triangle grid :

And this offers more options since different distances will produce equilateral and other triangles.

So this would let me make the final lamp smaller and denser.