[vtkusers] render point set as point cloud

[anast.jm at pg.com]

I have a vtkPolyData set of just unstructured points (no connectivity, no
attributes) that I would like to render as a point cloud. I've tried
vtkPolyDataMapper and vtkDataSet Mapper but neither would produce the point
cloud when rendered. The man page for DataSetMapper states it needs cell data
which I don't have so I'm assuming PolyDataMapper  wants the same?? Is there a
filter I could run my point set through to get the render to show the point
cloud? I 'm  tempted to try glyphing each point but thought there must be a
simpler way. Any suggestions appreciated....john