Distance computation for canal surfaces using cone-sphere bounding volumes

A canal surface is the envelope of a one-parameter set of moving spheres. We present an accurate and efficient method for computing the distance between two canal surfaces using a set of cone-spheres as bounding volumes. For two canal surfaces, we use the distances between their bounding cone-spheres to approximate their distance; the accuracy of this approximation is improved progressively by subdividing the canal surfaces into more segments and using more cone-spheres to bound the segments, until a pre-specified threshold is reached. Experimental comparisons show that our method is more efficient than Lee et al.'s method (Lee et al., 2007). 2012 Elsevier B.V. All rights reserved.