# ExtractControlPolygon

## <img src="https://3375153115-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F5uhW8FwQpXQj8tHUULMo%2Fuploads%2FYk45IF608cARBxu5ScQd%2FG3_09_SUBD_EXTRACT_CONTROL_POLYGON.png?alt=media&#x26;token=e1554ab7-b16e-49d3-96f0-884fbe4482c1" alt="" data-size="line"> ExtractControlPolygon <a href="#profiles" id="profiles"></a>

The ExtractControlPolygon command fits a polyline through the control points of a curve or a polygon mesh through the control points of a surface.

### **Steps**

1. Select curves or surfaces.\
   This creates polylines and/or meshes that have vertices at the original objects' control points.

### Supported input

* Curves, Polycurves, Surfaces
* SubDs

### Command-line option

* OutputLayer:&#x20;

  Specifies the layer for the results of the command.

  1. **Current**: Places the results on the current layer.
  2. **Input:** Places the results on the same layer as the input curve.

     *Note: If the input object is in a model that is attached using Worksession, the object will be                 placed on the current layer.*
  3. **TargetObject:** Places the results on the same layer as the target surface.
* SubCrv:&#x20;

  Type subcrv to select part of a curve as input.

For more information, please refer to the [Rhino documentation](https://docs.mcneel.com/rhino/8/help/en-us/commands/extractcontrolpolygon.htm#\(null\)).