# GH_PreviewUtil class

Namespace: [Grasshopper.Kernel](https://developer.rhino3d.com/api/gh1/namespace/grasshopper.kernel.md) · Assembly: [Grasshopper](https://developer.rhino3d.com/api/gh1/assembly/grasshopper.md)

```cs
public sealed class GH_PreviewUtil : IDisposable
```

This class exposes functionality that makes it easy to draw temporary geometry in Rhino viewports.

## Constructors

- [GH_PreviewUtil](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/ctor.md): (2 overloads)

## Properties

- [Enabled](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/enabled.md): Gets or sets the enabled state of this Preview util.
- [WireColour](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/wirecolour.md): Gets or sets the colour to use for Preview geometry.

## Methods

- [AddBox](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addbox.md): Add a box to the temporary Preview lists.
- [AddBrep](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addbrep.md): Add a brep to the temporary Preview lists.
- [AddCurve](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addcurve.md): Add a curve to the temporary Preview lists.
- [AddLine](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addline.md): Add a line to the temporary Preview lists.
- [AddMesh](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addmesh.md): Add a mesh to the temporary Preview lists.
- [AddPlane](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addplane.md): Add a plane to the temporary Preview lists.
- [AddPoint](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addpoint.md): Add a point to the temporary Preview lists.
- [AddVector](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/addvector.md): Add a vector to the temporary Preview lists.
- [Clear](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/clear.md): Clear all temporary geometry.
- [Dispose](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/dispose.md)
- [Redraw](https://developer.rhino3d.com/api/gh1/type/grasshopper.kernel.gh-previewutil/redraw.md): Forces a redraw the the viewports.