8

1008 Chapter 9: Sur face Modeling
their original orientations. Sometimes normals of
objectsthathavecomeinto3dsMaxaspartofa
DXF file are irregular, depending on the methods
used to create the objects. Use this func tion to
correct them.
Flip Normal Mode—Flips the normal of any face you
click. To exit, click this button again or right-click
anywhere in the program interface.
Tip: ThebestwaytouseFlipNormalmode
is to set up your viewport to display w ith
Smooth+Highlight and Edged Faces on. If you use
Flip Normal mode with default settings, you’ll be
able to flip a face away from you, but you won’t be
able to flip it back. For best results, turn off I gnore
Backfacing in the Selection rollout. This lets you
click any face and flip the direction of its normal,
regardless of its current direction.
Material group
Set ID—Lets you assign a particular mater ial ID
(page 3–1063)
number to selected sub-objects for
use with
multi/sub-object materials (page 2–1403)
and other applications. Use the spinner or enter
the number from the keyboard. The total number
of available IDs is 65,535.
Select ID—Selects sub-objects corresponding to
the Material ID specified in the adjacent ID field.
Type or use t he spinner to specify an ID, t hen click
the Select ID button.
[Sel ect B y Name]—This drop-down list shows
the names of sub-materials if an object has a
M ulti/Sub-Object material assigned to it. Click
the drop arrow and choose a sub-material f rom
the list. The sub-objects that are assigned that
material are selected. If an object does not have
a Multi/Sub-Object material assig ned, the name
list is unavailable. Likewise, if multiple objects
areselectedthathaveanEditPatch,EditSpline,
orEditMeshmodifierapplied,thenamelistis
inactive.
Note: Sub-material names are those specified in the
Name column on the material’s Multi/Sub-Object
Basic Parameters rollout; these are not created by
default, and must be spe cified separately from any
material names.
Clear Sel ection—When on, choosing a new ID or
material name deselects any previously selected
sub-objects. When off, selections are cumulative,
so new ID or sub-material name selections add to
the existing selection set of patches or elements.
Default=on.
Smoothing Grou ps group
Use these cont rols to assign selected faces to
different
smoothing groups (page 3–1107) ,andto
select faces by smo othing group.
To assign faces to one or more s moothing groups,
select the faces, and then click t he number(s) of
the smoothing g roup(s) to assign them to.
Select by SG (Smoothing Group)—Displays a dialog
that shows the current smoothing g roups. Select
a group by clicking the corresponding numbered
button and clicking OK. If Clear S elect ion is on,
any previously selected faces are first deselected. If
Clear Selection is off, the new selection is added to
any previous selection set.
Clea r All—Removesanysmoothinggroup
assignments from selected faces.
Auto S mooth—Sets the smoothing groups based
on the angle between faces. Any two adjacent
faceswillbeputinthesamesmoothinggroupif
theanglebetweentheirnormalsislessthanthe
threshold angle, set by the spinner to the r ig ht of
this button.
Threshold—This spinner (to the r ight of Auto
Smooth) lets you specify the maximum angle
between the normals of adjacent faces that
determines whether those faces will be put in the
same smoothing g roup.