Hypotrochoid Drawer

Point at distance d from center of a circle radius r rolling inside a fixed circle radius R.

Fixed circle R 5

Rolling circle r 3

Pen distance d 5

Speed 1.0×

Curve color

Rainbow (color shifts as it draws)

Show rolling circle

Presets

Period repeats every 3 full turns (R/gcd(R,r) revolutions of the base circle).

x = (R−r)cos t + d·cos((R−r)/r·t)
y = (R−r)sin t − d·sin((R−r)/r·t)