Function PyVTKObject_Traverse

Wrapping/PythonCore/PyVTKObject.cxx:255–289

------------------------------------------------------------------------------

//------------------------------------------------------------------------------
int PyVTKObject_Traverse(PyObject* o, visitproc visit, void* arg)
{
  PyVTKObject* self = (PyVTKObject*)o;
  int err = 0;

  if (self->vtk_observers != nullptr)
  {
    unsigned long* olist = self->vtk_observers;
    while (err == 0 && *olist != 0)
    {
      vtkObject* op = static_cast<vtkObject*>(self->vtk_ptr);
      vtkCommand* c = op->GetCommand(*olist);
      if (c == nullptr)
      {
        // observer is gone, remove from list
        unsigned long* tmp = olist;
        do
        {
          tmp++;
        } while (*tmp != 0);
        *olist = *--tmp;
        *tmp = 0;
      }
      else
      {
        // visit the observer
        vtkPythonCommand* cbc = static_cast<vtkPythonCommand*>(c);
        err = visit(cbc->obj, arg);
        olist++;
      }
    }
  }

  return err;
}

//------------------------------------------------------------------------------
PyObject* PyVTKObject_New(PyTypeObject* tp, PyObject* args, PyObject* /*kwds*/)