source files: [cx]lsp.[ch]
(x <vector> <vector>)
This operator returns the cross-product of the given pair of vectors. The crossproduct is a vector perpendicular to both input vectors, with magnitude equal to the area of the parallelogram defined by the two input vectors, hence the crossproduct is useful for constructing surface normals, computing areas of triangular facets (take half the area of the parallelogram) and testing the vertex order of triangles (see if the vertex normal head winds up inside or outside the solid :).