[vtkusers] Bug in vtkRenderWindow

[Erik Sobel]

There seems to be a bug in vtkRenderWindow::WritePPMImageFile (vtk 3.1.1 / 
Win-NT sp4)

vtkRenderWindow::WritePPMImageFile - saves a ppm image of the renderWindow 
if the window is on top but, if the window is partially or totally obscured 
you get a ppm of whatever screen graphics are within the boundaries of the 
render window - this could be windows from other apps, menu bars - whatever 
is in the client area of the renderWindow.  It's kind of cool - like a 
handy screen capture utility.

-Erik