Autodesk Forge Design Automation Export Inventor .Dwg to AutoCAD .Dwg Error

Question

I have a Forge Design Automation app that is creating Inventor models and drawings. I want to export copies of the Inventor drawings as AutoCAD .DWG files.

The code I'm using is based off of the VBA snippet from the Inventor Programming/API documentation. The code works when I use it in a locally run application, however when it runs in the Forge Design Automation application, I am getting a "Parameter is Incorrect" exception during the DWGAddin.SaveCopyAs() method call.

private void ExportToACAD(InventorServer inventor, DrawingDocument dwgDoc)
{
    _logger.LogInformation($"Converting {dwgDoc.FullFileName} to AutoCAD .dwg");

    TranslatorAddIn DWGAddin = (TranslatorAddIn)inventor.ApplicationAddIns.ItemById["{C24E3AC2-122E-11D5-8E91-0010B541CD80}"];
    TranslationContext translationContext = inventor.TransientObjects.CreateTranslationContext();
    translationContext.Type = IOMechanismEnum.kFileBrowseIOMechanism;
    NameValueMap valueMap = inventor.TransientObjects.CreateNameValueMap();
    DataMedium dataMedium = inventor.TransientObjects.CreateDataMedium();

    if (DWGAddin.HasSaveCopyAsOptions[dwgDoc, translationContext, valueMap])
    {
        valueMap.Value["All_color_AS_Black"] = 1;
        valueMap.Value["Remove_Line_Weights"] = 1;
        valueMap.Value["Scaling"] = "Geometry";
        valueMap.Value["Model_Geometry_Only"] = 0;
    }

    dataMedium.FileName = outputFilePath;

    DWGAddin.Activate();

    DWGAddin.SaveCopyAs(dwgDoc, translationContext, valueMap, dataMedium);
}

Some things I have tried:

1. Making sure the DWG Translator is available when running in Forge
2. Confirming that the DrawingDocument is not null and is open
3. Removing the options being set with the NameValueMap
4. Tried changing the Inventor drawing type from Inventor .DWG to Inventor .IDW
5. Adding code to export to AutoCAD .dwg in an iLogic Rule to be run on the After Document Save event trigger.

When I tried using an iLogic Rule I noticed that it would work as expected when I had Inventor open and visible. However, it would fail with the same "Parameter is Incorrect" exception when Inventor was running when not visible from a local application.

Any help would be greatly appreciated. Thanks.

Answer 1

I'm not sure yet if it's an issue we can sort on our side or a limitation, but if you check the value of valueMap.Value["Export_Acad_IniFile"] it's something like T:\Aces\Jobs\8fb3ef0479b8471195b7efd94751a441\tmp\exportdwg270ENU.ini which is pointing at a file that does not exist.

One solution is to provide your own ini file (e.g. as part of the app bundle - see Store template documents in AppBundle) and set the value of valueMap.Value["Export_Acad_IniFile"] to that. You can find that file on your computer where Inventor desktop is installed or can create one in the DWG options dialog in Inventor and use that.

By the way, I could ony reproduce the error on the desktop at the very beginning. I think going to the DWG Export options dialog initialized things somehow and from then onwards your original code worked fine for me on the desktop, no matter what I did. Inventor visiblity made no difference either.

Just one extra note, I would place DWGAddin.Activate before DWGAddin.HasSaveCopyAsOptions