8

Legacy AutoCAD Import 543
locked to Leng th that results in a constant ratio of
Width to Length.
A Note on Large-Scale Drawings
If you attempt to import geometry that is created
very far from the origin or contains a very large
bounding box in tools like AutoCAD, the 3ds Max
viewports and transform tools do not respond
properly. When you use them, the cursor does not
move smoothly.
For example, if you have a file that is a m ile wide,
but your system units are millimeters, you have a
scene width of 1.6 million units, which is too great
a va lue. If you change your system unit to feet, this
is less taxing on the system.
If any side of the scene’s bounding box measures
larger than ± 1,000,000 system units, you wil l see
the following dialog:
Legacy Au toCAD Import
File menu > Import > Legacy AutoCAD (*.DWG)
The new AutoCAD DWG/DXF Import Options
dialog (page 3–537)
contains many improvements,
including enhanced DWG compatibility and
greaterusercontrolandcustomizability;however,
some things were also lost f rom the DWG Import
found in previous versions of the software. For this
reason, 3ds Max retains the legacy DWG Import
functionality.
Dif fer ences Bet ween New a nd Legacy
DWG I mpor t
Features Unique to the new DWG Import System
•SupportforallObjectARXcustomobjects
(ignored by the Legacy importer).
• Specialized support for Architectural Desktop
and Revit objects, including style/component
grouping and naming, style associations
for material and modifier propagation, and
material tr anslation and assignment.
• Specialized support for AEC Civil contour
objects (t r anslated into a Ter r ain object).
• SupportforRasterobjects.
• Support for axonometric named views
(translated into cameras with the Orthogonal
toggle turned on). Both importers can translate
perspective views.
•Supportforattacheddrawingxrefs.
•SupportforDXFfiles.
• Rescaling to imported drawings created with
units that differ from the 3ds Max system units.
• Ability to skip frozen layers, or to select specific
layers to import (or exclude) from a list.
• Ability to set shape rendering parameters
before importing to 3ds Max.
• Ability to maintain layer assignments from the
drawing file.
Features Unique to the Legacy DWG Import
System
•AutoCADprimitivesaretranslatedinto
3ds Max primitives.
• SupportforText(thoughnotMText).
• Imported blocks are represented as groups.