> For the complete documentation index, see [llms.txt](https://help3.depence.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help3.depence.com/depence-construction/nurbs.md).

# Nurbs

Nurbs are features that generate 3D geometry from [splines](/depence-construction/depence-splines.md).

![Example of Nurbs](/files/zNSpYAqq9gexlMbJtBeb)

## Usage

To add a nurbs feature from the 3D Hierarchy, click on "Add" and select your feature:

![Nurbs features](/files/LsykuHlL5EYeg38PNSzq)

All nurbs features require a spline to generate 3D geometry. The [spline](/depence-construction/depence-splines.md) must be a child of the nurbs:

![Sweep Nurbs](/files/Llr8vDQniPeqcM0e2OlQ)

### Sweep nurbs

Sweep nurbs will create tubes around the [spline](/depence-construction/depence-splines.md):

![Sweep Nurbs - Settings](/files/aCto6i1YApjB6XY7iIAF)

Its radius can be adjusted through the dimension properties.

### Extrude nurbs

Extrude nurbs will extrude the [spline ](/depence-construction/depence-splines.md)vertically to generate a volume:

![Extrude nurbs - Settings](/files/1eIEcas8etj9rz9KI4Rl)

Its depth can be adjusted through the dimension properties.