The upper sliders control the shape of the ellipse. The bottom left slider changes the y position of the ground. The bottom right slider changes the rolling speed and direction.
I was inspired me to make this by @s_federici's wonderful studio "Simplest ellipse drawing algorithm": https://scratch.mit.edu/studios/29609673/ I had to do a lot of experimenting to figure this out, and it was VERY rewarding when I finally came up with the solution :D Feedback is very welcome - maybe I made a mistake with the math, or maybe there is a more convenient/interesting/funny/... way of doing it. If so, I'd love to know. Read more about the concepts used in this project: https://en.wikipedia.org/wiki/Ellipse https://en.wikipedia.org/wiki/Trigonometry https://en.wikipedia.org/wiki/Pythagorean_theorem
