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432 Chapter 20: Managing Scenes and Projects
Each block is linked separately as a hierarch y,
w ith the block itself as the parent object and
itsconstituentpartsaschildobjects.Thechild
objects of the block are combined by layer.
Tip: This is usually the best option for file
linking. It preserves all ADT information, and
generally maintains the same granularity as you
would expect in A utoCAD .
•
Layer, B lock s as Node Hierarchy, Split by
Mater ial—
This works the same as the Layer,
Blocks as Node Hierarchy option, with the
following additional functionalities: The
combination of non-block objects by layer,
followed by material and support for multiple
materialsassignedtoACISsolidandpolymesh
geometry.
• Non-block object layer combination:
For example, take an A utoCAD file with six
objects in layer A: three have a Brick material
and three have a Stone material. Using this
option, this file would be linked to in the form
of two objects, or nodes, one containing the
Brick material and the other with the Stone
mater ial.
Each block is linked to separately as a hierarchy,
w ith the block itself as the parent object and
itsconstituentpartsaschildobjects.Thechild
objects of the block are combined by layer.
•Multiplematerialsupport
On import, ACIS solids and polymesh
geometry can support multiple materials.
For polymesh geometry, one material is
supported per face. For an ACIS solid, if the
solid has more than one material associated
w ith it, a multi/sub object material is created
that contains the materials used. If the solid
has only one material associated w ith it, a
standard/architectural material is assigned
instead.
Note: M ultiple material support for ACIS solids
applies to DWG files imported or file linked
from Revit Architecture 2008 or AutoCAD
Architecture (formerly Architectural Desktop
or ADT ) 2008 and later.
Note: This derivation method is intended for
use with AutoCAD 2007 (and later) format
files. Using this metho d with DWG files created
with previous versions of AutoCAD could
result in data loss.
•
Entity,BlocksasNodeHierarchy—Every linked
object not in a block is represented as a separate
object in the 3ds Max scene, without regard
to layers. The nodes are then placed on
scene layers that correspond to the drawing
layers. Each block is imported separately as a
hierarchy, with the block itself as the parent
object and its constituent parts as child objects.
The child objects of the block are combined by
layer.
One benefit of this option is that you can
apply instanced anima tion controllers (page
2–293) to block subcomponen ts and thus, by
transforming a single member, transform a ll
members at once. For example, in a scene
containing a conference table with six chairs
around it, you could move all of the chairs
simultaneously by moving a single chair.
Another advantage is that al l geometr y is
instanced, so edited UVs and normals and
other modifications need be done only once.
Note: This derivation metho d might cause
unreliable material propagation when
importing drawings containing dynamic
blocks. Materials might propagate to some
block instances and not to others.
Wa rn in g : This option has the potential to create an
enormous number of objects in your scene.
Multiple materials per object are supported
w ith this option, if needed. If the object is an
ACIS solid, and has more than one m aterial