2008

External References and Block Names
A linked AutoCAD or AutoCAD Architecture drawing can include xrefs that
reference files but use the same block names. 3ds Max keeps the blocks distinct
by prepending xref names to block names.
In Revit, a DWG, DXF or RVT file can be linked to the project. This kind of
link is called a
RVT Link on page 7913 . When the project is exported to a DWG
file, this type of link is represented in the exported drawing as an external
referenced drawing. In this case, more than one drawing file may be created,
with one referencing the other(s).
Circular References
An xref file that contains a sequence of nested references that refers back to
the xref file is considered a circular reference. 3ds Max resolves xrefs until it
detects a circular reference. For example, if you have the circular reference
A|B|C|A, 3ds Max detects and breaks the circularity between C and A. This is
consistent with the way AutoCAD and AutoCAD Architecture handle circular
xref dependencies.
Overlay External References
3ds Max treats overlay xrefs in the same way as AutoCAD when resolving
xrefs.
For more information regarding overlay xrefs, refer to your AutoCAD User
Reference.
Cloning Actively Linked Objects
If you want to clone actively linked objects, you should only use the Copy
option. Creating references or instances of actively linked objects is not
recommended, as reliability issues can arise when the instanced or referenced
object is deleted in the linked file.
When you copy actively linked objects, linked through the
File Link Manager
on page 6783 , the copies are automatically converted to editable mesh or editable
spline objects. If your selection contains several objects which instance another
object, the resulting copies also instance the same object.
Compound Objects Containing Actively Linked Objects
If you use an actively linked object as part of a compound object, you should
always choose Copy when you specify how the linked object is transferred to
6780 | Chapter 21 Managing Scenes and Projects