In this paper we consider the novel idea of closest feature maps (CFMs) applied to refinable collision response in order to address the potential issues and problems associated with over approximation of contact information for time-critical collision detection schemes that utilise sphere-tree bounding volume hierarchies. Existing solutions to time-critical collision handling can at times suffer from overapproximation of required contacting data, which may lead to undesirable or implausible physical response. Our CFM solution essentially utilises information for contact data approximation based on the underlying geometry of the colliding objects rather than potentially problematic properties of the contacting bounding volumes. The merits of the scheme lie in its simplicity and effectiveness to handle refinable collision data in an efficient manner and could quite easily be extended to incorporate other types of bounding volume hierarchies for interruptible collision handling. r 2006 E...