Topological subtleties for molecular movies

Synchronous movies permit visual analysis of shape perturbation during molecular simulations. The molecule is conceptualized as a knot and modeled as a spline curve. As the molecule writhes, the graphics approximation in each frame should display an ambient isotopic image of the perturbing spline. These graphics approximations raise subtleties for correctly rendering the embedding. A cautionary example was discovered through visualization experiments and the relevant characteristics are formally proved.