Tic-tac-toe illusion
Equations :
The basic shape is produced by these two equations, one for each ellipse.
- Curve((cos(a π) cos(t) - sin(a π) sin(t), cos(t)) / 2, t, 0, 2π)
- Curve((-cos(a π) cos(t) + sin(a π) sin(t), cos(t)) / 2, t, 0, 2π)
- Flatten(Sequence(Sequence(Curve((cos(a π + j π / 3 + i π / 4) cos(t) - sin(a π + j π / 3 + i π / 4) sin(t) + 3i, cos(t) + 3j) / 3, t, 0, 2π), i, 1, 3), j, 1, 3))
- Flatten(Sequence(Sequence(Curve((-cos(a π + j π / 3 + i π / 4) cos(t) + sin(a π + j π / 3 + i π / 4) sin(t) + 3i, cos(t) + 3j) / 3, t, 0, 2π), i, 1, 3), j, 1, 3))