I always interested in parametric design. I'm very curiosity on grasshopper for Rhino, and processing.The spirograph is a geometric drawing toy that produces mathematical curves of the variety technically known as hypotrochoids and epitrochoids( from Wiki). Spirograph is beautiful and fabulous. However, people usually draw 2D spirograph. I want to transform 2D spirograph to 3D. By rotating X, Y, Z-axis to make it 3D, we could draw variable complex spirograph. You can control parameters such as twist, curve strength and curvature etc.