Xref moves in linked dwg

[gordolake]

Hi all, Has anyone had a xref's dwg in a linked autocad dwg move in relation to the base dwg to what appears to be its own absolute origin in autocad when imported.

Base acad dwg with cadastral info in which a 3d survey dwg and floor plans of proposed dwellings are xrefed, all looks fine in autocad.

Import to revit loads dwg ok and objects in dwg are in correct location except for xrefed parts.

any insight would be appreciated.

Thanks Steve

[aggockel50321]

Which of the xrefed drawings were off?

I've had some issues with imported dxf files generated by our total station software (TDS Forsight DXM), where the survey points come in flipped on the xy plane.

[gordolake]

Very frustrating that importing dwg with xref has problems.

The objects are well away from 0,0 origin ie map grid and in millimetres.(may be a precision problem )

dwg has xref scaled by 1000 (seeams to throw xref part of dwg way off coordinates or it centers this part because it so far from origin)

This error message shows up when "Some numerical data within theimported file was out of range. the data has been truncated"

Only way to get this process to work is to divide the dwg up into parts ie no xrefs and have objects in each dwg close to 0,0


Steve

[Wes Macaulay]

What you can also do is link (has to be linked) the file in and move it into place. Publish the Revit coords back into the DWG and Revit writes a UCS into your DWG to record its new location / orientation. The DWG stays where it ought and you can carry on.

You'll still be hooped if the DWG contains entities which are a long (say a mile) way apart; delete any entities not in the region of your project before linking it in.

I believe Revit won't (by design) deal with large coordinate systems because it messes up how it tesselates curves -- perhaps a limitation of OpenGL representation of objects. We need a programmer here to REALLY explain why this is in Revit...

[gordolake]

Thanks very much Wes for your detailed reply.

I can see that the opengl limitations could be the issue here.

I will have to be more careful compiling the base autocad info and learn shared coords to save this stress.


Thanks

Steve.