This is a rather a collection of important modules and a demonstration of the visualisation
than an instrument.
The path of the neutrons through the bender is shown; the colour changes after the first 
reflection. Additionally the arriving of the neutron at the detector is monitored using the 
visual module.
The visualisation during the simulation is not yet satisfactory - we will work on that - but 
postscript files are generated so that one can look at the pictures after the simulation. 
Unfortunately these files and the 'surface files' are saved in the VITESS directory 
(e.g. 'C:\Program\VITESS') instead of the parameter directory; this will be changed in the 
next version.
The SNS source with the hydrogen moderator is used. Gravity was included in the simulation.
The use of the module 'straight Fermi chopper' is demonstrated as well as the use of the 
module 'powder_sample'. 
A cylindrical detector with its center at the exact backscattering position is used. Roughly 
the whole backscattering is regarded; it can be seen in 'visual.ps'. For this simulation, 
'RadialBender.gui' (with a high number of trajectories) is used. For the visuatisation of 
the bender, 'RadialBenderPS.gui' (with only 1000 trajectories) is used.