[vtkusers] multiple inheritance or RTTI

[Stefano Perticoni]

Hi,
Deriving from vtk classes is it a good practice to use multiple inheritance
or should i use only single inheritance and RTTI if i want to insert an
object vtkPegasus in a list together with vtkHorse and vtkBird objects?

1)  class vtkPegasus : public vtkHorse, public vtkBird {}

2) class vtkPegasus : public vtkHorse {}
   //Main
    vtkHorse*  pvtkHorse =new vtkHorse
    vtkHorse*  pvtkHorse =new vtkPegasus
    list<vtkHorse*>  lHorse
    //RTTI
   vtkPegasus* pvtkPegasus=dynamic_cast<vtkPegasus*>(
   traversing the lHorse list...)
   //
   if (pvtkPegasus)
    //ok, it's a vtkPegasus*
   else
    //it's just a vtkHorse

Should i use 1) or 2) ?
I ask this question because reading online man pages vtk source
seems to use single inheritance only.
Thanks,Stefano