[vtkusers] Problems with visualizing multiple scalars on vtkDataSetMapper

[Sarah Macumber]

Hi, 
 
I have 2D / 3D data so I am using an vtkUnstructuredGrid & a vtkDataSetMapper to visualize my data.  My data has several associated scalar values which I want to be able to switch between for coloring purposes.  Calling SetScalars with the new scalar value does not update the visualization pipeline as described in this thread :
Grid.GetCellData().SetScalars(currentScalars);

http://www.vtk.org/pipermail/vtk-developers/2007-September/004700.html <http://www.vtk.org/pipermail/vtk-developers/2007-September/004700.html> 

but I still don't fully understand what to do about it.  

What is the best way to switch your viewable scalar value on a vtkUnstructuredGrid?

Thanks, Sarah