What she didn’t tell us is that this is just one set of primaries, and that term “primary colors” simply refers to any collection of three or more colors that can be combined to form a gamut of other colors. Subtractive and additive primary colors (Click image to see a larger version - Image source: Max Maxfield) When I was a kid, my teacher told us that the primary colors were red, yellow, and blue, and that we could make other colors by mixing these primaries (red + yellow = orange, blue + yellow = green, and red + blue = purple). This leads us to the topic of primary colors. In practice, however, we want to use a small subset of colors that are as bright and vibrant as possible. Next, I decided to light the drips up with random colors, but which colors should we use? Theoretically, since each pixel has red, green, and blue color channels, each of which can have 2^8 = 256 values numbered from 0 to 255, we can achieve 2^24 = 256 x 256 x 256 = 16,777,216 different hues, shades, tints, and tones. The duration of each drip is random, as is the inter-drip delay (i.e., the delay between adjacent drips).Īs an aside, while I’m thinking about it, I should perhaps mention that you can see videos of all of this in action on the Cool Beans YouTube Channel (make sure to tell your friends LOL). The way we implement this algorithm, each drip appears in a random location, turns hard on, and then turns hard off again. We start with individual drips lighting their associated pixels (ping pong balls) with white light one at a time. In the September 2020 issue of PE, which - due to the vagaries of print publishing - will hit the streets in the first week of August, we visualize the array as laying flat on the floor with drips of virtual water falling on it from above. As I also mentioned, I’ve been documenting the ongoing development of this project in in my monthly Cool Beans and Programming Tips and Tricks columns in Practical Electronics (PE), which is the UK’s premier electronics, computing, hobbyist, and maker magazine ( PE is available around the world in both print and digital formats). As I mentioned in an earlier column, I’m currently having a lot of fun with my Awesome 12 x 12 Ping Pong Ball Array.

Color drips