A friend of mine was attending a ball hosted by her university. The theme of the ball was stars and constellations and so she wanted to attend the dance in a dress that was lit up with LEDs acting as twinkling stars. Seven of the 28 stars are aligned to resemble the Big Dipper constellation and twinkle differently than all of the rest, which each twinkle in a random pattern.
The LEDs came from a NeoPixel strip that we then cut up and soldered into a string. The LEDs were then sewn into specific places on the dress. Each LED can be controlled individually to set it to one of 16 million different colors. The whole string was controlled by an Arduino microcontroller running this code. The Arduino was powered by a rechargeable battery and a voltage converter. This is all taped together into a small bundle that fits into the back of the dress.
21 of the stars are lightly magenta in color and twinkle randomly in a ‘random walk’ with a bias towards the current direction. The seven stars that form the Big Dipper scroll through a gradient of three colors continuously. Rather than calculate the values of each step in the gradient as the program runs, a lookup table is used instead.