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336 Chapter 5: Creating Geometry
Alignment
If two Bo olean operands are perfectly aligned
without actually intersecting, the Boolean
operation might produce the wrong result.
Although this is rare, if it does occur, you can
eliminate it by making the operands overlap
slightly.
Relative Comp lexity B etween Operands
Boolean works best when the two operands are
of similar complexity. If you wish to subtract
text (a complex object made of many faces and
vertices) from a box without any segments, the
result is many long, skinny faces that are prone to
rendering errors. Increasing the number of box
segments produces b e tter results. Try to maintain
a similar complexit y between operands.
Coplanar Faces/Colinear Edges
Previously, Boolean required that objects overlap.
If two objects did not overlap but merely touched
an edge to an edge, or a face to a face, the Boolean
would fail.
Boolean allows for non-overlapping objects.
Coincident faces/edges and vertices are no longer
aproblem.Youcanuseobjectscompletelyencased
w ithin another object, where no edges intersect,
to create Booleans.
See a lso
Collapse Utility (page 1–948) to create
Booleans with multiple objects.
See also
Fixing Bo olean Problems (p age 3–979)
Pr ocedur es
To create a Bool ean object:
1.
Select an object. This object becomes operand
A.
2. Click Boolean. The name of operand A appears
in the Operands list on the Parameters rollout.
3. On the Pick B oolean rollout, choose the copy
method for operand B: Reference, Move, Copy,
or Instance. (These methods are described in
the Pick Boolean rollout section, later in this
topic.)
4. On the Parameters rollout, choose t he Boolean
operation to perform: Union, Intersection,
Subtraction (A-B), or Subtract ion (B-A). You
canalsochooseoneoftheCutoperations,
described later in the Operation group section.
5. On the Pick Boolean rollout, click Pick
Operand B.
6. Click in a viewport to select operand B. 3ds Max
performs the Boolean operation.
The operand objects remain as sub-objects
of the Boolean object. By modifying the
creation parameters of the Boolean’s operand
sub-objects, you can later change operand
geometryinordertochangeoranimatethe
Boolean result.
Example: To create and modify a single object that
contains multiple B ooleans:
Suppose you want to create a bo x with two holes
in it. One hole is to be cut by a sphere, and the
second by a cylinder. If you want to make changes
tothesphereorthecylinderlater,youcandoso
by following these steps:
1. CreateaBooleanfollowingthestepsinthe
previous sec tions. The original object ( the box)
isconvertedtoaBoolean,andisdesignated
operand A. The second object (the sphere) is
converted to operand B.
2. D eselect the Boolean object. Build the cylinder
if it does not already exist.
3. Select the Boolean object; and under
Comp ound Objects, click B oolean again.
4. Click Pick Operand B and click the cylinder in
the v iewport. It is conver ted to operand B.