The Artist's Husband: HSLA
· the artists husband generative art rust nannou color hsl hsla rgb 
You may have noticed that, in my Nannou apps, I tend to use hsla colors. hsla is hsl plus an alpha channel, a, to control transparency. The hsl part defines the color. hsla stands for hue, saturation and lightness. In this color model, hue is the color itself. You can think if it as being chosen from a color wheel. In many implementations, this number is a number of degrees (0 to 360) or radians (0 to 2pi). In Nannou, it is a number from 0.0 to 1.0. Note that, because of the circular nature of the hue, 0.0 and 1.0 are the same color! Look at the image at the top of this post. It displays hues from 0.0 (along the bottom) to 1.0 (along the top). 0.0 is red. increasing it cycles through all the colors of the rainbow, and back to red at 1.0. If you were to keep going past 1.0, the colors would all repeat. For example, you would find that 1.1 is the same color as 0.1.