[vtkusers] vtk and python - some questions.

[David Gobbi]

Hi Prabhu,

I've made some massive changes to the python wrappers that
should be useful to you.  They'll appear in the nightlies
tomorrow (they're already in CVS).


The VTK/Python objects now have two special attributes:

__class__    the VTK/Python class that the object belongs to

__this__     returns a SWIG-style mangled 'this' pointer 


The new VTK/Python classes also have special attributes:

__bases__    the base clases of this class, as a tuple

__methods__  all the methods for this class

__name__     the name of the class, e.g. 'vtkActor'

__module__   the module the class is defined in, e.g. libVTKCommonPython

__doc__      a doc string for the class, currently empty


The methods also have __doc__ strings that return the
C++ prototypes for that method.  The format of these doc strings
is likely to change in the future.


The new VTK/Python classes and objects have a similar 'look & feel'
to Python's own classes and class instances, however, you cannot
derive a Python class from a VTK/Python class unless you write your
own wrapper class.


To list all the methods for a particular object or class, you can use the
following:

def vtkdir(c):
  try:
    c = c.__class__
  except AttributeError:
    pass
  d = c.__methods__
  d.insert(0,"from " + c.__name__ + ":")
  for b in c.__bases__:
    for m in vtkdir(b):
      if not m in d:
        d.append(m)
  return d


Finally, I've moved most of the implementation of the wrappers out
of vtkWrapPython.c and into common/vtkPythonUtil.cxx.  This will
make future modification of the wrappers much easier.

 - David

--
  David Gobbi, MSc                    dgobbi at irus.rri.on.ca
  Advanced Imaging Research Group
  Robarts Research Institute, University of Western Ontario