9.5.2

548 • CHAPTER 10
STRUCTURE MENU • 549
Cross Section
The splines must be selected in the Object manager.
Figure 1. Figure 2.
Figure 3. Figure 4.
With this interactive tool, you can create cross sections for a group of splines; we’ll refer to these as
‘rail splines’.
Cross sections are always created at right angles to the current view. You should therefore select a
view in which you can see the rail splines directly from the side.
Figure 1 shows some splines before any cross sections have been created. If you activate the Cross
Section tool, you can drag to draw a line where a cross section is to be created.
In Figure 2, three cross-sections have been created. In the 3D viewport you can that this has created
circles (more or less) that are wrapped around the four rail splines (Figure 3). These cross sections are
new splines with Bezier type interpolation. These cross sections are especially useful when used as
children of a Loft NURBS object. The order of these rail splines within the Loft NURBS is important.
When working with more than two rail splines, make sure that these are placed in the correct order
within themselves in the Object manager, because CINEMA 4D uses this object order when creating
the cross sections. The start point of the cross section spline is located on the rst rail spline and the
end point on the last.
If the rail splines wind around themselves, giving a cross section spline that overlaps with the rail
splines, CINEMA 4D selects the rst intersection in the direction of travel of the spline (Figure 4).