9

DWG Files 931
scene. You would have to edit the motion of the
ball on many frames to make even a simple change.
Usingadummyobjecteasilysolvesthisproblemby
breaking the motion into two simple components.
One component is the bounce of the ball. The
other is the path through the scene.
DWG Files
TheDWGfileistheprimary,nativefileformat
of dra wing files created by A utoCAD, Autodesk
Architectural Desktop, and Autodesk Mechanical
Desktop®. It is a binar y format used for importing
and exporting (page 3–550) AutoCAD drawing
files.
Yo u c a n a l s o u s e t h e File Link Manager (page
3–422) to create a live link between a drawing
filethatcanbeopeninAutoCADand3dsMax.
Changes that are made to the drawing can
automatically be updated in 3ds Max without
having to reload scenes or re-import drawings.
DXF Files
DXF f i les are used to import and export objects
to and f rom AutoCAD (and other programs that
support this file format).
Keep the following in mind when you are creating
your DXF geometry, and when you are deciding
whether to convert by layer, color, or entity:
• With AutoCAD Release 12, if you are using
the AutoCAD Advanced Modeling Extension
(AME), use the SOLMESH command on your
AME models prior to saving the .dxf fi le.
• Af ter importing a DXF file, you m ight want to
divide the resulting 3ds Max file into smaller
objects.
Entities that are frozen or turned off are ignored.
The successful unification of face normals depends
on the welding of coincident vertices. Sometimes,
depending upon the precision of the model as it
wascreatedinAutoCAD,theverticesmaynot
becloseenoughtobeconsidered"coincident."
They will not be welded, and the faces w ill not be
properly unified. In this case, increase the Weld
Threshold value in the Import DXF File dialog.
Converting by layer can result in objects consisting
of many elements (page 3–933). In cert ain cases,
some of these elements may have all of their face
normals flipped the wrong way. You can detect this
in the software by turning off Backface Cull in the
Display panel, or by rendering the objects. Use the
Normal modifier (page 1 –746) to correct this.
If you do not want to flip normals, you can either
use 2-sided materials, or turn on the Force 2-Sided
option in the Render Scene dialog.
If you are loading a large scene containing
thousandsofentities(suchas3Dfaces)andhave
chosen to load an object by entity, the conversion
can take a long time. It also produces a huge
number of objects to handle in the software. To
avoid this, organize your DXF file so that these
kinds of entities are grouped by layer, then make
the conversion by layer rather than by entity.
Dynaflector
A space warp (page 3–1014) that lets particles
affectobjectsinadynamicssituation.
Three kinds of space warps are in the dynaflector
category:
PDyn aFlect Space Warp (page 2–81)
SDynaFlect Space Warp (page 2–85)
UDy naFlect Space Warp (page 2–86)
See also
Omniflector (page 3–984)