DISPLAY_BSPLINE_POINTS_ON displays the control and
interpolation points of specified B-splines.
+-----------<---------+
| |
--->(DISPLAY_BSPLINE_POINTS_ON)----+----|B-spline(s)|----+---->
This action has no options.
Use this action to display the control and interpolation points
which define the shape of a B-spline, in the active viewports.
The following parameter sequence turns on the display points of the
specified spline(s).
DISPLAY_BSPLINE_POINTS_ON [specify spline(s)]
DISPLAY_BSPLINE_POINTS_OFF terminate action