Summary: Model validity, especially of manifold boundary representation (B-rep) models, has long been recognized as an important problem. This paper reviews issues on model validity of existing models. In particular, we present a set of sufficient conditions for representational validity of a typical B-rep data structure; we propose a rectify-by-reconstruction approach to the B-rep model rectification problem, and present results on the inherent complexity of the corresponding boundary reconstruction problem. Further, we develop the concept of an interval solid model, associated with a solid, for achieving numerical robustness. Finally, we present a set of sufficient conditions so that an interval solid model is “approximately equal” to its associated solid.
For the entire collection see [Zbl 0946.00021].