[vtkusers] Grab function in VTk4 (vtkrenderer windows)

[Farshid Dehmeshki]

Hi all;
in one application in vtk version3*  I used Grab  function in the vtkRendererwindow class for capture the renderer windows.
when I wanted to convert my codes to vtk4 I realized that this function does not exist anymore in this class.
(the aim of this function was that capture the renderer windows and create a ppm file as output.)
the grab function in 
does any body know how can capture windows now (by vtk)  in the vtk 4+.
thank you in advance
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Farshid  Dehmeshki
Software Engineer 
Medicsight Plc
46 Berkeley Square
London
W1J 5AT
Tel : 020 7598 4074
Fax: 020 7598 4071
Email : farshid.dehmeshki at medicsight.com
Web Site : www.medicsight.com
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