Extension Attributes on a NURBS curve node.
Render Curve
By default, NURBS curve nodes are not rendered. Turning on this attribute will make them renderable.
Start Width
End Width
Specifies the root and the tip width, respectively. NURBS curve are rendered as flat ribbons. The widths are specified in object space.
Illumination From This attribute allows specifying an object set; the lights contained in that set will be used to illuminate the object. By default, only light sources that have the Illuminates by Default option enable will light the object. The Illumination From extension attribute is a work around for issues caused by the fact that some Maya nodes are renderable by 3Delight but considered non-renderable by Maya; Maya prevents non-renderable objects from being used with the light-linking mechanism and its shader assignment mechanism. To address the light-linking limitation, use the Illumination From extension attribute. To assign a shader on such a node, you can use one of the materials button in the 3Delight Shelf, or the 3Delight Assignment Panel.