Introduction

The Rhino SDK provides the class CRhinoGetObject (MRhinoGetObject in Rhino.NET), that will allow you to interactively select objects on the screen. This is a large class with a number of options. It is recommended that you read through the header file, rhinoSdkGetObject.h, before using.

To use the CRhinoGetObject class, simply put one on the stack and call it's GetObjects() member. It is possible to derive custom classes from CRhinoGetObject . But, the class is powerful enough that deriving new class from it is usually unnecessary.

If an instance of CRhinoGetObject was successful in selecting one or more objects, then use it's Object() member to retrieve information about the object that was selected. The Object() member returns a CRhinoObjRef class which has a number of member functions to help you quickly get to the information you are looking for.

Example 1 - Select a single object

C++

  CRhinoGetObject go;
  go.SetCommandPrompt( L"Select object" );
  CRhinoGet::result res = go.GetObjects( 1, 1 );
  if( res == CRhinoGet::object )
  {
    const CRhinoObjRef& obj_ref = go.Object( 0 );
    const CRhinoObject* obj = obj_ref.Object();
    if( obj )
    {
      // TODO
    }
  }

VB.NET (Rhino 4)

  Dim go As New MRhinoGetObject()
  go.SetCommandPrompt("Select object")
  Dim res As IRhinoGet.result = go.GetObjects(1, 1)
  If (res = IRhinoGet.result.object) Then
    Dim obj_ref As MRhinoObjRef = go.Object(0)
    Dim obj As IRhinoObject = obj_ref.Object()
    If (obj IsNot Nothing) Then
      ' TODO
    End If
  End If

Example 2 - Select one or more objects

C++

  CRhinoGetObject go;
  go.SetCommandPrompt( L"Select objects" );
  CRhinoGet::result res = go.GetObjects( 1, 0 );
  if( res == CRhinoGet::object )
  {
    int i, count = go.ObjectCount();
    for( i = 0; i < count; i++ )
    {
      const CRhinoObjRef& obj_ref = go.Object( 0 );
      const CRhinoObject* obj = obj_ref.Object();
      if( obj )
      {
        // TODO
      }
    }
  }

VB.NET (Rhino 4)

  Dim go As New MRhinoGetObject()
  go.SetCommandPrompt("Select objects")
  Dim res As IRhinoGet.result = go.GetObjects(1, 0)
  If (res = IRhinoGet.result.object) Then
    Dim count As Integer = go.ObjectCount()
    For i As Integer = 0 To count - 1
      Dim obj_ref As MRhinoObjRef = go.Object(i)
      Dim obj As IRhinoObject = obj_ref.Object()
      If (obj IsNot Nothing) Then
        ' TODO
      End If
    Next
  End If

Example 3 - Select a single curve object

C++

  CRhinoGetObject go;
  go.SetCommandPrompt( L"Select curve" );
  go.SetGeometryFilter( CRhinoGetObject::curve_object );
  CRhinoGet::result res = go.GetObjects( 1, 1 );
  if( res == CRhinoGet::object )
  {
    const CRhinoObjRef& obj_ref = go.Object( 0 );
    const ON_Curve* crv = obj_ref.Curve();
    if( crv )
    {
      // TODO
    }
  }

VB.NET (Rhino 4)

  Dim go As New MRhinoGetObject()
  go.SetCommandPrompt("Select curve")
  go.SetGeometryFilter(IRhinoGetObject.GEOMETRY_TYPE_FILTER.curve_object)
  Dim res As IRhinoGet.result = go.GetObjects(1, 1)
  If (res = IRhinoGet.result.object) Then
    Dim obj_ref As MRhinoObjRef = go.Object(0)
    Dim crv As IOnCurve = obj_ref.Curve()
    If (crv IsNot Nothing) Then
      ' TODO
    End If
  End If