9.5.2

222 • CHAPTER 7
OBJECTS MENU • NURBS • 223
A polygon should have one neighbor only per edge, otherwise the surface will tear. Sometimes you
can repair a torn surface with the Optimize command from the Functions menu.
Here two polygons overlap each other on the left side of the object — as a result, the polygon on the
right has more than one neighbor and the surface is torn.
Only connected polygons are rounded. To see which polygons are connected, select a surface, then
use Selection > Select Connected. If you want to connect overlapping polygons, use the Functions
> Optimize command.
The sides of the cube are not connected to one another (left). The cube on the right is one piece.
Two shortcuts are especially useful when modeling with HyperNURBS.
 (1) Q switches the HyperNURBS on and off, i.e. toggles between cage display
and subdivision surfaces display.
 (2) Hold down the 9 key to temporarily switch on the Live Selection tool.
Drag over points, edges or polygons (whichever mode is active) to select.