9

Fixing Boolean Problems 887
All the cylinders are a single object.
5. SelecttheBoxandmakesureithasLength,
Width, or Height Segs values that are g reater
than 1.
See CreasesorridgesshowinBooleanobjects
(page 3–xii).
6. OpentheCreatepanelandfromthedrop-down
menu that shows Standard Primitives, choose
Compound Objects.
7. Click the B oolean button and in the Parameters
rollout > Operations group, make sure
Subtraction (A-B) is turned on.
8. On the Pick Boolean rollout, click Pick
Operand B, and select the Cylinders.
Thecylindersaresubtractedtoformholesinthebox.
You only have to perform Bo olean operations once
instead of several times. This method is far more
efficient and less prone to errors. It is also very
useful for cutt ing rough openings for doors and
windows into a wall if you’re already working with
3D geometry. Next, you’ll find an example for
working with 2D spline objects.
Splines and B oolean Operations
Performing Boolean operations on splines made
from the Create panel > Shapes menu c an be
confusing. 2D spline shapes do not use the
Boolean operation you’d use for 3D geometr y.
Shapes, converted to Editable Splines, offer
Boolean functionality from the Modify panel >
Geometry rollout. U nlik e Boolean operations
performed on two separate pieces of 3D geometry,
Boolean operations can only be performed on
single splines.
Therefore, one of two things must be done before
you can perform Bo olean operations to spline
shapes.
•Whenoriginallycreatingtheshapes,makesure
Start New Shape is turned off on the Create
panel > Shapes > Object Type rollout. When
turned off, you can create several overlapping
shapes that are treated as a single shape made
up of several splines.
Start New Shape in the OFF state (it is on, by default.)
• If you didn’t turn off Start New Shape, you’ll
have to attach all the spline shapes to create a
single shape comprised of multiple splines.
To illustrate the most common situation, let’s say
you’ve got three overlapping rectangles and you