C3D 2009 objects not seen in C3D 2009 xref after 'save as'

[AbsKelvin]

I have two files:

mainsheet.dwg (C3D 2012), which xrefs:

basexref.dwg (C3D 2009)

Viewing mainsheet in 2012, all C3D objects (surface, survey points, pipes) in basexref are seen without a problem.

mainsheet.dwg is then 'saved as' C3D 2009 using C3D 2012. At this point, supposedly, both mainsheet.dwg and basexref.dwg are now in C3D 2009 (the 2007 format).

Now when mainsheet.dwg is opened in C3D 2009, it does not recognize the C3D objects (they don't appear) that are in basexref. I have attempted to reload and detach/re-attach the xref, same result.

The current workaround is to 'export' basexref from C3D 2012 to 2009. This wipes all C3D objects converting all viewable elements to polylines and points. With this newly exported basexref.dwg, mainsheet can now 'see' all elements of basexref.

As you can surmise, this is a real bummer workaround. Just wondering if anyone has encountered something similar. Thanks for any input.

Kelvin

[mathewkol]

"Everyone" has experienced this issue. C3D is not backwards compatible in the manner you're looking for. There is no reasonable workaround. Any C3D drawing will NEVER be readable in ANY previous version. It's essential to keep everyone on the same platforn.

[mathewkol]

The best you can do is set PROXYGRAPHICS to 1 before saving in 2012 to give you a fighting chance of simply viewing C3D objects in previous versions.

[AbsKelvin]

Matt,

Many thanks for the response. The PROXYGRAPHICS options will certainly help in some situations.

Although, I don't believe I communicated the problem as well as I should have. Essentially, the base map (which contains the C3D objects) was assembled in 2009, and it was _never_ modified using 2012. We were, however, xref'ing the basemap to a 2012 sheet. So, it was only the parent sheet that was saved down to 2009; no C3D objects are embedded in this parent sheet.

The thinking (incorrectly to be sure) was that since the 2012 sheet is xref'ing a 2009 dwg, the display of the xref shouldn't change when the sheet is later saved down to 2009. This is not the case, unfortunately. It's further perplexing that the errors continue to be seen even after the basemap is detached and then re-attached (done in 2009).