# HiddenLineDrawingSegment 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 sealed class HiddenLineDrawingSegment
```

The results of HiddenLineDrawing calculation are a collection of segments. A segment is a sub-curve of a HiddenLineDrawingObjectCurve.

## Properties

- [CurveGeometry](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.hiddenlinedrawingsegment/curvegeometry.md): The actual curve geometry
- [CurveSideFills](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.hiddenlinedrawingsegment/curvesidefills.md): The SideFill fields are only valid for visible curves. With respect to the HiddenLineDrawing, the region to the left (or right respectively) of this curve is described by CurveSideFills[0] or CurveSideFills[1], respectively. If exactly one of these regions is empty this is a scene silhouette. If this region contains a surface it is either a surface which in 3-D is adjacent to this edge or it an surface that is further away from the camera, we call this a shadow surface. unknown is used for unset values and for projecting curves
- [Index](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.hiddenlinedrawingsegment/index.md): Index of this curve in HiddenLineDrawing.Curves.
- [IsSceneSilhouette](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.hiddenlinedrawingsegment/isscenesilhouette.md): Returns true if this curve is a scene silhouette.
- [ParentCurve](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.hiddenlinedrawingsegment/parentcurve.md): This curve is a sub-curve of the returned HiddenLineDrawingFullCurve object.
- [SegmentVisibility](https://developer.rhino3d.com/api/rhinocommon/type/rhino.geometry.hiddenlinedrawingsegment/segmentvisibility.md): Returns the segment's visibility