Generating Topological Information from a "Bucket of Facets"

The STL de facto data exchange standard for Solid Freefonn F*brication represents CAD models as a collection of unordered triangular planar facels. No topological connectivity information is provided; hence the term "bucket of facet." Such topological information can, however, be quite useful for performing model validity checking and speeding subsequent processing operations such as model slicing. lfhis paper discusses model topology and how to derive it given a collection of unordered tri,ngular facets which represent a valid model.