A new program for 3D editing of digital terrain models (DTMs) has been released by Carlson Software. P3D Topo offers many benefits:â€¢ Load and review the two most common formats for surfaces: LandXML and DXF files of 3D Faces, in addition to TIN and Grd files from Carlson Software. â€¢ Overlay other LandXML file types such as points, alignments, parcels, storm and sanitary sewers, culvert pipes and other piping systems. â€¢ View the 3D Surface with user-controlled textures to quickly spot errors in the DTM. â€¢ Fix the errors in the DTM for re-saving and use in CAD programs, or for direct output for machine control and survey stakeout.