# Nurbs

Nurbs are features that generate 3D geometry from [splines](https://help.depence.com/depence-construction/depence-splines).

![Example of Nurbs](https://content.gitbook.com/content/SJPsyh5CBOise9BtVNGO/blobs/DHo6C78Zrb8BITCRi6cp/Nurbs.png)

## Usage

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

![Nurbs features](https://content.gitbook.com/content/SJPsyh5CBOise9BtVNGO/blobs/djf0zOwUoutBHpTZCKwj/Nurbs-Menu.png)

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

![Sweep Nurbs](https://content.gitbook.com/content/SJPsyh5CBOise9BtVNGO/blobs/3LeOsoCBxJRsALJzUOoo/nurbs-sweep.png)

### Sweep nurbs

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

![Sweep Nurbs - Settings](https://content.gitbook.com/content/SJPsyh5CBOise9BtVNGO/blobs/mGi6WRihfmFHSMd9jDsM/Sweep-Nurbs-settings.png)

Its radius can be adjusted through the dimension properties.

### Extrude nurbs

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

![Extrude nurbs - Settings](https://content.gitbook.com/content/SJPsyh5CBOise9BtVNGO/blobs/Jqf5qKTSBDF2cbMmdUpl/Extrude-Nurbs-settings.png)

Its depth can be adjusted through the dimension properties.