[vtkusers] Odd behavior in vtkStreamTracer?

[Bridgman, William T.]

Hello,

I've been generating some field lines using vtkStreamTracer.  The  
domain of the field has a hole in the center and I am interested in  
the flow into and out of the hole.

I've defined my points just outside the spherical hole.  The northern  
region has outbound field lines and those are easy.  The southern  
region has inbound field lines so I set StreamTracer to reverse the  
direction of propagation.  In the southern case, the lines seem to  
generate okay but are actually *two* nearly perfectly overlaid lines  
with an outbound and inbound components that seem to have a common  
node at a position far from the hole.

I've not yet identified a clear pattern in when it does this.  It does  
not happen to every field line in the region.

I'm using a CVS repository around version 5.2, Linux on 64-bit.

Any thoughts?

Thanks,
Tom
--
Dr. William T."Tom" Bridgman               Scientific Visualization  
Studio
Global Science & Technology, Inc.          NASA/Goddard Space Flight  
Center
Email: William.T.Bridgman at nasa.gov         Code 610.3
Phone: 301-286-1346                        Greenbelt, MD 20771
FAX:   301-286-1634                        http://svs.gsfc.nasa.gov/