smoothmodel                         :model file
4                                   :#interfaces in model
plotcolors                          :model colors file
m                                   :first plot descriptor (mq)
rwell1                              :receiver well coordinates
wg                                  :receiver plot descriptor (wgq)
d                                   :shooting mode (dg)
swell4                              :source well coordinates
don't care                          :file containing coords. of sources
ws                                  :source plot descriptor (wsq)
rt                                  :r to plot rays       
demo11                              :output file name
  0.  90.                           :range of takeoff angles 
1.  .1   2.                         :coarse, fine angle increment; ray density 
4000.  6000. 10000.  6000. 20000.   :velocities
n                                   :direct wave?
n                                   :primaries?
n                                   :head waves?
h  2 1 2
h  4 3  
