To Edit a Surface by Manipulating Control Points
1. Click
Style >
Surface Edit. The
Surface Edit tab opens.
2. Select a surface to edit. A 4 x 4 mesh appears on the surface.
3. To set a boundary constraint, right-click a mesh boundary and choose a constraint from the shortcut menu.
4. To change the mesh resolution, enter a value in the Max Rows and Columns boxes.
5. To set the degree for the rows and columns:
a. Make sure that Advanced Options is selected on the Options tab.
b. Enter a value in the Degree Rows and Columns boxes.
6. Select an option from the Move box.
7. To define movement for the control points surrounding the selected point, select a Filter option:
◦ 
—Moves all selected points the same distance as the active point.
◦ 
—Drops the motion of the selected points off linearly in relation to the distance from the active point.
◦ 
—Drops the motion of the selected points off quadratically in relation to the distance from the active point.
8. Select one or more control points to move:
◦ Drag them to a new position.
◦ Nudge them as follows:
1. Type a value in the Adjust box to set the nudge increment.
2. Click anywhere in the graphics window to activate it.
3. Press the arrow keys on the keyboard or click the arrow buttons on the tab.
9. To set the number of rows or columns that use each knot:
a. Click the Options tab.
b. Make sure that Advanced Options is selected.
c. Enter a value in the Rows per Knot and Columns per Knot.
10. To set the smoothness of the rows or columns:
a. Click the Options tab.
b. Make sure that Advanced Options is selected.
c. Make sure that Keep Base Surface is not selected.
d. Under Global Smoothness, select a value from the Rows and Columns list.
11. Click
.