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636 Chapter 20: Managing Scenes and Projects
Weld T hresh old —
Determinesthesizeofthearea
which vertices must occupy to be welded. Vertices
w ith distances equal to or less than this va lue are
welded into a single vertex.
Weld —Turns on the Weld Ver tices f unc t ion. In
most cases, you should leave this box turned on
because unwelded objects can’t be unified or
smoothed.
Use Thr eshold—If on, STL import uses the
standard 3D Studio welding method. This can be
a very slow process.
Quick Weld—If on, STL import uses a welding
algorithm optimized for the STL format. This is
up to thirty times faster than standard 3D Studio
welding, and is highly recommended.
Auto-Smooth group
Auto-Smooth—Applies
smoothing g roups (page
3–1107)
to the geometry based on the smoothing
anglesetbythesmoothanglespinner. Edges
between faces that have an angle between them
that is greater than the specified smoothing angle
will appear faceted in the rendered image. Edges
between faces that are below the specified angle
are smoothed
Smooth Angle—Determines the size of the
smoothing angle.
Auto-Smooth—Tur n s on t he Auto-Smooth
function.
Miscellaneous group
Remove Double Faces—Removes one of the pair
wherever two faces are occupying the same
location. Recommended.
Unify Normals—Forces the
normals (page 3–1074)
of all faces on each object to face the same way
(usually out). If, when yo u render y our scene, the
face normals are pointing in the wrong direction,
use the Normal modifier to flip them. For best
results, leave this box turned on.
Expor ting to ST L
File menu > Export > StereoLitho (*.STL)
An STL file saves object data in a format used
for stereolithography. STL files have a file-name
extension of
.stl
.ThereisanASCIISTLformatas
well as a binary STL format. You can choose w hich
to create when you export a 3ds Max scene.
STL files are generally used for purposes of rapid
prot otyping. A variety of methods use the STL
format to construct prototypes. For example,
many STL machines use a liquid polymer and
harden it in small slices, creating a solid plastic
model. Other STL machines use metal powder to
create a model in steel. Still other machines use
aspecialwax.
An STL object m ust define a complete and closed
surface. You can check w hether the geometry you
wanttoexportsatisfiesthiscriterionbyusingthe
STL Check modifier (page 1 –825)
.
You can also import STL fi les. See
Importing STL
Files (page 3–635)
.