TRIANGULATION performs triangulation of a set of 3D points width compulsory interconnections between the points. The outcome is represented by 3DFACE entities. ISOLINES determines the curves of intersection of a set of 3DFACE entities width a set of plane equidistances horizontally or vertically. The outcome is made up of POLYLINE entities optionally interpolated. VOLUME determines volume and center of gravity of a body limited by 3DMESH and 3DFACE entities. 3DINTERSECTION determines the intersection curves between 2 sets consisting of 3DFACE or 3DMESH entities. The outcome is represented by 3DPOLY entities.