9

Boolean Operation 919
B ool ean Opera ti on
The fence is operand A, and the cat is operand B.
Upper left and right: A minus B
Second to upper left: B minus A
Second to lower left: Union
Lower left: Intersection
A Boolean object combines two objects by
performingaBooleanoperationonthem. In
the software, a Boolean object is made from two
overlapping objects. The orig inal two objects are
the operands (A and B) and the Boolean object
itself is the result of the operation.
For geometry, the Boolean operations are:
• Union: The Boolean object contains the volume
of both original objects. The intersecting
or overlapping portion of the geometry is
removed.
• Intersect ion: The Boolean object contains
onlythevolumethatwascommontoboth
origina l objects (in other words, where they
overlapped).
• Subt ra ct i on (or di f f eren ce): The Boolean
object contains the volume of one original
object with the intersection volume subtracted
from it.
Bound Vertex
Binding spline vertices via the Refine and Bind
functions in Editable Spline (Ver tex) (page 1–297)
is useful for connecting splines when building a
spline network for use with the Surface Modifier
(page 1–842).
Bound vertices are black, allowing them to be
easily disting uished from standard vert ices. You
cannot move a bound vertex directly. However,
changing the segment length by scaling it or by
moving a connected vertex causes the bound
vertex to shift its position in order to remain at
the segment’s midpoint. You can change a bound
vertex’s type (right-click the vertex, and then
choose the type f rom the bottom of the right-click
menu), and if you conver t it to a Bezier or B e zier
corner, you can manipulate its handles.
Bounding Box
Bounding box shows the extents of the model boat.
Theboundingboxisthesmallestboxthatencloses
the maximum dimensions or extents (page 3–936)
of an object.
You can display selected objects in the scene as
bounding b oxes to speed up screen redraw. Use
the Object Properties dialog (page 1–117).