[vtkusers] picking in a vtkTkImageViewerWidget

[Lederer, Maitland]

Hey users-

I'd like to pick a point in a vtkTkImageViewerWidget using a
vtkPropPicker and I'm running into a problem.  The picker is not finding
any vtkProps, despite the fact that there is one in the renderer's
vtkPropCollection.  Can anyone offer any suggestions?  Some of my code
(Tcl/Tk) is below.

Any help appreciated.  Thanks muchly.

-Maitland

set ::rf2D [vtkTkImageViewerWidget $::renderFrame.r2f -width 1024
-height 1024]
[$::rf2D GetImageViewer] SetColorWindow 255
[$::rf2D GetImageViewer] SetColorLevel 128
# slider for 2D view
scale $::renderFrame.s2 -orient horizontal -command SetVisibleSlice \
    -from [lindex $::extent 4] -to [lindex $::extent 5] -length 1000
grid $::rf2D -row 1 -column 2 
grid $::renderFrame.s2 -row 2 -column 2
::vtk::bind_tk_imageviewer_widget $::rf2D
bind $::rf2D <KeyRelease> { } 
bind $::rf2D <Expose> "$::rf2D Render"

**************************
M. Maitland Lederer
Staff Engineer 
Foster-Miller, Inc.
(781)684-4618