My undergraduate math professor, Tom Banchoff, always loved using Dupin’s cyclides as geometric examples. When I was a student, we used a software package called Fnord to visualize the cyclides, amongst many other complex curves and surfaces.

Tom is retiring this year, so I thought it would be fun to revisit one of the “classic” Fnord demos. Below, you’ll see a simple striped cyclide rendered in much the same fashion as the original cyclide.fnorse. Like that demo, there’s a slider to manage rotation in the fourth dimension, around the XW-plane.

I’m always amazed by the march of technology. Work on Fnord began in 1990, before the web even existed. If Fnord were rebuilt today, the web would certainly be a natural (even phenomenal) fit.

XW: 0 π/2
Divisions: 21 61
view x: -π/2 π/2
view y: -π/2 π/2
view z: -π/2 π/2