# BlendSurfaceOptions class

Namespace: [Rhino.Geometry](https://developer.rhino3d.com/api/rhinocommon/namespace/rhino.geometry.md) · Assembly: [RhinoCommon](https://developer.rhino3d.com/api/rhinocommon/assembly/rhinocommon.md)

```cs
public class BlendSurfaceOptions
```

Settings for [Brep.CreateBlendSurface(BrepFace, BrepEdge, Interval, bool, BrepFace, BrepEdge, Interval, bool, BlendSurfaceOptions, double)](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.brep/createblendsurface.md). The defaults give the result of the BlendSrf command when its dialog is accepted unchanged. Properties ending in 0 apply to the first edge, those ending in 1 to the second.

## Properties

- [Bulge0](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/bulge0.md): Scale factor for the blend's tangent lengths at the first edge, the Bulge setting of BlendSrf. Must be greater than zero. The default is 1.0.
- [Bulge1](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/bulge1.md): Scale factor for the blend's tangent lengths at the second edge, the Bulge setting of BlendSrf. Must be greater than zero. The default is 1.0.
- [Continuity0](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/continuity0.md): Continuity of the blend at the first edge. The default is [BlendContinuity.Curvature](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendcontinuity.md).
- [Continuity1](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/continuity1.md): Continuity of the blend at the second edge. The default is [BlendContinuity.Curvature](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendcontinuity.md).
- [InteriorShapes](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/interiorshapes.md): True to add blend shapes at the edit points of the edges when the edges are compatible, the Interior shapes setting of BlendSrf. Has no effect when [BlendSurfaceOptions.Refine](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/refine.md) is true. The default is true.
- [PlanarSectionDirection](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/planarsectiondirection.md): Direction the planar sections are parallel to. Used only when [BlendSurfaceOptions.PlanarSections](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/planarsections.md) is true. Must be a valid, nonzero vector. The default is the world z axis.
- [PlanarSections](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/planarsections.md): True if every blend shape lies in a plane parallel to [BlendSurfaceOptions.PlanarSectionDirection](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/planarsectiondirection.md), the Planar sections setting of BlendSrf. The default is false.
- [Refine](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/refine.md): True to fit the blend to tolerance instead of making the simple blend that compatible edges allow, the Refine setting of BlendSrf. The default is false.
- [SameHeight](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.blendsurfaceoptions/sameheight.md): True to give every blend shape the height of a shape spanning the average of the gaps at the two ends of the blend, the Same height setting of BlendSrf. The default is false.