Home > Supported File Formats > DWF to DGN

How to convert DWF (DWFx) to DGN (MicroStation)?

PolyTrans|CAD+DCC performs mathematically precise CAD, DCC/Animation, GIS and BIM 3D file conversions into all key downstream 3D packages and file formats. Okino software is used and trusted throughout the world by many tens of thousands of 3D professionals in mission & production critical environments, backed by respectable personal support directly from our core development team.

DWF

Okino knows of the DWF file format very well as we have been involved with its evolution since the year 2000. A DWF file is nothing other than a renamed "ZIP" file which contains other internal assets such as a HOOPS HSF 3D model file and several XML files used to describe meta data and other aspects of the model. You can rename the .dwf file to .zip and then open it in any ZIP handling software.

The HSF file format was created by Ithaca Software in the mid 1980's as an efficient, light weight, compressed 3D visualization format. Thereafter it was adapted and adopted by Tech Soft 3D in the early 2000s for use by Autodesk as a "3D variation" of its prior 2D-vector-centric DWF file format (and hence how HSF became DWF). DWF/HSF is considered a "polygonal mesh" file format and not a NURBS/solids MCAD file format.

DWF attained acceptable traction after 2006 when Autodesk made it a primary conduit to export high quality 3D visualization data from its main CAD products such as AutoCAD, Navisworks, Revit and Inventor. Okino considers DWF as one of its most important non-MCAD file formats to bring in very large 3D models (such as massive oil & gas rigs, 3D plants and refineries) from these 4 aforementioned Autodesk products as well as from AVEVA PDMS software.

DGN

DGN is a 2D/3D file format, with its roots going back to the early 1980s, that is used as the native file format of such programs as Bentley's MicroStation and Intergraph's PDS software packages. Relative to deep history, DGN could be considered a competitor or rival to the Autodesk DWG file format. Okino considers both DGN and DWG rather "crude" and old file formats, depending on what vintage of file is used and whether the files contain ACIS-SAT/Parasolid "BREP solids" geometry or just 2D/3D vector geometry.

Okino considers a DGN V8 file to be of two varieties: (1) "GIS" like models defined using basic primitives like lines, curves, arcs and 3D objects defined by the extrusion and revolution of these basic elements - these types of files are typically glutted with an enormous number of basic elements which can result in massive scenes that can very slow to display and take up a lot of memory. (2) The second variety of DGN file uses the more modern "BREP solids" geometry type to define the 3D objects as lighter weight and more efficient NURBS surfaces and solids.

Okino spent over 20 years developing its DGN importers and exporters. As such, we understand the nuances of DGN and its related conversion issues. Please refer to our DGN importer WEB page which has extensive information on (1) the history of DGN and when to use DGN, (2) how to import massive DGN files (such as PDMS 3D plants, oil refineries, etc), (3) how to import from AVEVA PDMS and Intergraph PDS, and (4) our suggestions about using STEP or VRML2 as alternative conversion methods from Bentley's MicroStation.

DWF import converter's overview

DGN export converter's overview