[vtkusers] Re: circle

[Goodwin Lawlor]

Hi Isabelle,

> I would like to draw a circle each time and where exactly the user 
> clicks on my displayed image.
>  
> I saw examples to draw a sphere:
>  
>  *vtkSphereSource* m_sphere = vtkSphereSource::New();
>  vtkActor*  m_sphereActor = vtkActor::New();
>  vtkPolyDataMapper* sphereMapper = vtkPolyDataMapper::New();
>  sphereMapper->SetInput(m_sphere->GetOutput());
>  m_sphereActor->SetMapper(sphereMapper);
>  m_Renderer->AddActor( m_sphereActor );
> * 
> But is there a way to draw a circle (that is *empty disk* and in *2D*) 
> instead of a filled sphere in 3D?

Have a look at the vtkRegularPolygonSource class- I'm not sure which 
version of VTK it appeared in though.

hth

Goodwin