This is a companion discussion topic for the original entry at https://happycoding.io/examples/p5js/creating-classes/loopers
Tangled color fun. What makes the tail fade away?
Thanks! And good question. All of the magic happens in this line of code at the top of the
draw() function is called 60 times per second, and this line of code draws a dark gray (32 on a scale of 0-255) background on top of the previous frame. The trick is that the 3 is the opacity, so the background is mostly transparent. That means the previous frames show through the background, and only after a few frames does the gray add up enough to actually hide what was drawn in the previous frames.
I’m not explaining that very well, but to see what I mean, try removing that line altogether, or changing the 3 to a different number.
I use a line like that pretty often, because it’s one of the easiest ways to take a program like this to the next level. It looks really cool and like you’re doing complicated things, when in reality all you’re doing is slapping on a thin layer of paint.
Oooh, love it! Thanks for explaining the magic.