[C++-sig] Type conversion problem

[Randall Hopper]

     I'm trying to update the PyOSG wrappers to allow access to an array
type returned from a C++ class method.  

     All attempts to call a Python method on the returned array or it's
elements (even print it), result in a Boost.Python.ArgumentError (error msg
at bottom).

Here's the wrap of the array class (osg::Vec3Array):

  namespace PyOSG {
  void init_ArrayVec3()
  {
      TemplateCompArray<osg::Vec3Array, osg::Vec3> Vec3Array("Vec3Array");
  }
  }

and here's a piece of the referenced template:

  using namespace boost::python;

  template <typename T, typename BT>
  class TemplateCompArray
  {
    public :
      TemplateCompArray(const char * name) : _array(name, boost::python::no_init) {
          _array
              .def(init<>())
              .def(init<int>())
              .def("__init__", make_constructor(&create_from_tuple))
              .def("getNumElements", &T::getNumElements)
              .def("__getitem__", &getitem, return_internal_reference<>())
              .def("__setitem__", &setitem, return_internal_reference<>())
              .def("resize", &resize)
              .def("__str__", &str)
              ...
      static std::string str(T * self)
      {
        ...
      }
  }

Any idea why printing (or calling a Python method of the wrapped Vec3Array
in Python should generate a type error?  It's like boost.python doesn't
realize the TemplateCompArray instantiation "is" Vec3Array.

Thanks,

Randall

P.S. If you want to see the full source for context, check out:

  http://mosca.caltech.edu/pyosg_downloads/pyosg_ads_15.tar.gz

and look in osg/ArrayVec3.cpp and include/TemplateCompArray.hpp.

------------------------------------------------------------------------------
Traceback (most recent call last):
  ...
  File "osg_to_sgg.py", line 147, in setupGeode
    print geom.getVertexArray()
Boost.Python.ArgumentError: Python argument types in
    Vec3Array.__str__(Vec3Array)
did not match C++ signature:
    __str__(osg::TemplateArray<osg::Vec3f, (osg::Array::Type)10, 3, 5126>*)