This topic describes how to import Autodesk® Navisworks® data to the IFC format.

Conversion Module Dependencies

To get access to the functionality for importing NWD files to IFC, load the following:

• Module that contains functionality for importing from an NWD file to an IFC file:

  Binary library: Nv2Ifc.tx.

  Source Code Location: Exchange/Exports/Nv2Ifc.

• Module for conversion between .dwg and IFC formats:

  Binary library: Dwg2Ifc.tx.

  Source Code Location: Exchange/Imports/Dwg2Ifc.

Conversion Public API

There are two abstract classes that describe the interface for conversion of data from BimNv format to IFC format:

• OdNv2IfcModule — Interface of the BimNv-to-IFC conversion module.

  An example of this interface implementation is represented with the OdNv2IfcModuleImpl class.

• OdIfcExport — Interface for an object that provides the BimNv-to-IFC conversion functionality. This interface contains the doExport() method which should contain the conversion implementation in inherited classes. Conversion properties can be retrieved through a properties() method call.

  An example of this interface implementation is represented with the OdIfcExporter class.

The OdIfcExportProperties class stores and handles the set of conversion properties.

Import Prerequisites

Add the following include and define declarations to your application source code to get access to the BimNv-to-IFC conversion functionality:

      
#include "OdaCommon.h"
#include "NwHostAppServices.h"
#include "StaticRxObject.h"
#include "NwDatabase.h"
#include "RxDynamicModule.h"
#include "DynamicLinker.h"
#include "ExSystemServices.h"
#include "diagnostics.h"
#include "ExPrintConsole.h"

#include "ModuleNames.h"

#include "../Exchange/Exports/Nv2Ifc/Include/IfcExport.h"
#include "../Exchange/Exports/Nv2Ifc/Include/IfcExportProperties.h"

#define STL_USING_STREAM
#define OD_HAVE_FSTREAM_FILE
#define STL_USING_STRING
#include "OdaSTL.h"
      
    

For static configurations, use the set of DECLARE/DEFINE_STATIC macro instances:

      
#if !defined(_TOOLKIT_IN_DLL_)
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdDbRootModuleObject);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(NwDbModule);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdSDAIModule);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdIfcCoreModule);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdIfc4Module);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdIfcGeomModuleImpl);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdIfcBrepBuilderModule);
  ODRX_DECLARE_STATIC_MODULE_ENTRY_POINT(OdNv2IfcModuleImpl);
  ODRX_BEGIN_STATIC_MODULE_MAP()
  ODRX_DEFINE_STATIC_APPMODULE(OdDbRootModuleName, OdDbRootModuleObject)
  ODRX_DEFINE_STATIC_APPMODULE(sNwDbModuleName, NwDbModule)
  ODRX_DEFINE_STATIC_APPMODULE(OdSDAIModuleName, OdSDAIModule)
  ODRX_DEFINE_STATIC_APPMODULE(OdIfcCoreModuleName, OdIfcCoreModule)
  ODRX_DEFINE_STATIC_APPMODULE(OdIfc4ModuleName, OdIfc4Module)
  ODRX_DEFINE_STATIC_APPMODULE(OdIfcGeomModuleName, OdIfcGeomModuleImpl)
  ODRX_DEFINE_STATIC_APPMODULE(OdIfcBrepBuilderModuleName, OdIfcBrepBuilderModule)
  ODRX_DEFINE_STATIC_APPMODULE(OdNw2IfcModuleName, OdNv2IfcModuleImpl)
  ODRX_END_STATIC_MODULE_MAP() 
#endif
      
    

It is assumed that the following classes are declared and defined for implementation of the conversion:

• The OdExNwSystemServices class which implements platform-dependent functionality for the conversion process.

            
  class OdExNwSystemServices : public ExSystemServices
  {
  public:
    OdExNwSystemServices() {}
  };
            
          

  This class is inherited from the ExSystemServices class.

• The MyNwServices class which implements functionality for host application services.

            
  class MyNwServices : public OdExNwSystemServices, public OdNwHostAppServices
  {
  protected:
    ODRX_USING_HEAP_OPERATORS(OdExNwSystemServices);
  };
            
          

Also, there are three variables that store the necessary information for the import process:

• sNvFile — Contains the full path to the input BimNv file.
• sIfcFile — Contains the full path to the output IFC file.
• sDictionaryFile — Contains the full path to the dictionary file. The dictionary file stores the correlation between entities from the input BimNv database and the output IFC file.

      
OdString sNvFile;
OdString sIfcFile;
OdString sDictionaryFile;
      
    

Import Properties

You can handle the import process by using the properties in the table below:

Parameter Name	Parameter Description
IFC Schema Version	IFC schema version for the output IFC file. Imported data is written to the file according to the specified schema version.
IfcFilePath	The full path to an output IFC file should be created as a result of the conversion operation.
Database	A smart pointer to an object of the BimNv database to import data from.
Dictionary	A conversion map that contains the correlation between entities in the input BimNv database and the output IFC file.

Import BimNV Data

To use the import functionality in your IFC SDK-based application:

1. Create an instance of a previously declared custom services class:

             
   OdStaticRxObject <MyNwServices> svcs;
             
           

2. If you use the static configuration, initialize the module map:

             
   #if !defined(_TOOLKIT_IN_DLL_) 
     ODRX_INIT_STATIC_MODULE_MAP();
   #endif
             
           

3. Initialize BimNv SDK and load the main BimNv module:

             
   odrxInitialize(&svcs);
   ::odrxDynamicLinker()->loadModule(sNwDbModuleName, false);
             
           

4. Add a try ... catch() section for handling errors:

             
   try 
   {
   
   }
   catch (const OdError& e) {
     nRes++;
     odPrintConsoleString(L"\nException Caught: %ls\n", e.description().c_str());
   }
   catch (...)
   {
     nRes += 2;
     odPrintConsoleString(L"\nUnknown Exception Caught\n");
   }
             
           

   All of the following code fragments are added to the try{} section.

5. Read the input BimNv file:

             
   OdNwDatabasePtr pNwDb = svcs.readFile(sNvSource);
             
           

6. Load the BimNv-to-IFC conversion module and create a converter object:

             
   NV_IFC_EXPORT::OdNv2IfcModulePtr pModule = ::odrxDynamicLinker()->loadModule(OdNw2IfcModuleName, false);
   auto pExport = pModule->create();
             
           

7. Create a dictionary and prepare its contents:

             
   std::map < OdString, OdString > dictionary;
   if (dictionaryFilePath.isEmpty())
     return eNoFileName;
   
   std::ifstream dictionaryFile(dictionaryFilePath.operator const char* ());
   std::string key, value;
   while (dictionaryFile)
   {
     if (dictionaryFile >> key)
     {
       if (dictionaryFile >> value)
       {
         dictionary[key.c_str()] = value.c_str();
       }
     }
   }
             
           

8. Set conversion properties:

             
   NV_IFC_EXPORT::OdIfcExportPropertiesPtr pProperties = pExport->properties();
   pProperties->put_SchemaVersion((OdInt16)kScmIfc4);
   pProperties->put_Database(pNwDb);
   pProperties->put_IfcFilePath(sIfcDestination);
   pProperties->put_Dictionary(createRxWrapper(dictionary));
             
           

9. Run the export process:

             
   pExport->doExport();
                       
           

10. Uninitialize BimNv SDK:

              
    ::odrxDynamicLinker()->unloadUnreferenced();
    ::odrxUninitialize();
              
            

    Deinitialization code should be placed outside the try{} catch() section.

See Also

ExNv2IfcExport Sample Application