This week on MacBreak Studio, I show Steve Martin from Ripple Training how to build a virtual Etch-a-Sketch© in Motion.
Following up from our Spirograph© episode based on a viewer request, I use Motion to recreate a toy that was popular in my childhood that let you draw on a screen by turning two knobs: one to draw vertically, and the other to draw horizontally.
I used a particle emitter to make the line and linked its X and Y position values to the rotational values of the knobs so that as you turn each knob, the emitter moves, leaving behind a trail of particles much like a pen or pencil would do.
Once everything is hooked up, the real fun begins: animating the knobs to turn using a variety of parameter behaviors to create different patterns. It's a great learning tool for understanding how parameter behaviors can be applied. Try it yourself to see what you can come up with.