9

Boolean Compound Object 341
Alignment
If two Boolean operands are perfectly aligned
without actually intersecting, the Boolean
operation mig ht produce the wrong result.
Although this is rare, if it does occur, you can
eliminate it by making the operands overlap
slightly.
Relative Complexity Between 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 b ox
segments produces better results. Try to maintain
a s imi lar complexit y between operands.
Coplanar Faces/Colinear Edges
Previously, Boolean required that objects ov erlap.
If two objects did not overlap but merely touched
an edge to an edge, or a face to a face, the B oolean
would fail.
Boolean allows for non-overlapping objects.
Coincident faces/edges and vertices are no longer
aproblem.Youcanuseobjectscompletelyencased
w ithin another object, w here no edges intersect,
to create Booleans.
See also Collapse Utility (page 1–966) to create
Booleans with multiple objects.
See also
Fixing Boolean Problems (page 3–885)
Pr ocedur es
To create a Boolea n object:
1.
Select an object. This object becomes operand
A.
2. Click B oolean. The name of operand A appears
in the Operands list on the Parameters rollout.
3. On the Pick Boolean 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 the Bo olean
operation to perform: Union, Intersection,
Subtraction (A-B), or Subtraction (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 Booleans:
Suppose you want to create a box 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 se ctions. 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 c yl inder
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 viewport. It is converted to operand B.