An add-on for AUTOCAD or BricsCAD, which determines the intersection curves between 2 sets consisting of 3DFACE, 3DSOLID or 3DMESH entities. The outcome is represented by 3DPOLY entities. It can also generate 3DFACE entities, perpendicular to a POLYLINE for obtain cross sections, can generate horizontal 3DFACE entities for obtain isolines and it can draw the conversion to 3DFACE of the 3DSOLID entities.