[vtkusers] Running multiple render windows for shared dataset

[Jenny Simpson]

I have a piece of software written using the Tcl interface to Vtk.  It
loads a large dataset, renders it, and adds 3D annotations to it.

I would
like to be able to
run arbitrarily many instances/sessions of this program on one machine
without
actually loading a dataset more than once.  In this way the
machine could act as a server to serve independent render
requests on a single dataset.

Obviously, running n
separate processes won't work because then I'd have to load the dataset n
times, which is too much data to have in memory.  I've thought loading the
dataset first, then using threads for each separate rendering window so
that the vtk data actor is only created once but can be rendered and
manipulated by many separate threads.  Is this even possible in Vtk?
Based on the documentation I've read, it seems that some parts of Vtk are
thread-safe and others are not.

I've
played around with Tcl threads, but they're not very well developed yet
and I keep running into problems, although I'm new to Tcl threads so it
may just be a learning curve.

I'd appreciate any suggestions on how I might go about solving this
problem and what
programming language I should use (maybe I shouldn't even be trying this
in Tcl).

Thanks,

Jenny Simpson
SCI Institute
University of Utah