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978 Chapter 9: Surface Modeling
Geome try rollout Subdivision group
Subdivide—Subdivides selected elements. Select
one or more elements, and then click Subdivide.
Propagate—When on, extends the subdivision to
neighboring patches. Propagating the subdivisions
along all contiguous patches prevents patch cracks
where you have attached patches together.
Topology group
Cr e a te—Creates a three or four-sided patch on
existing geometry or in free space. First turn on
Create and then click geometry or free space in the
view por ts to create a quad or a tri patch.
The cursor changes to white cross hairs w hen over
an existing patch vertex. Select an existing vertex
by clicking it. Click in free space to create a new
vertex at that location; this vertex is included in the
sequence of ver tices for the new patch.
To create a Tri Patch :Clickthreetimesinfreespace
or on existing vertices. Right-click, or left-click
oneoftheverticesinthecurrentsequenceto
complete the creation of a Tri Patch.
To c r e at e a Qu a d Pat c h :Clickfourtimesinfree
space or on existing vertices. The Quad Patch will
be automatically created after the fourth click.
No operation will take place if you right-click or
selectavertexinthecurrentsequencewhenonly
one or two vertices are in the sequence.
Detach—Lets you select one or more elements
within the current object and then detach them (or
copy them) to form a separate patch object.
Reorient—When on, the detached p atch element
copies the position and orientation of the source
object’s creation Local coordinate system. The
new detached object is moved and rotated so that
its Local co ordinate system is positioned and
aligned with the origin of the cur rent active grid.