NAME
          DtEnvGetAttenuation - Get the global attenuation value of
          the scene.

     SYNOPSIS
          #include <Dt.h>

          void DtEnvGetAttenuation( float *a2, float *a1, float *a0 )

     DESCRIPTION
          DtEnvGetAttenuation() returns the global attenuation value
          value of the scene.  The a2, a1, and a0 parameters are the
          squared, linear and constant cooeffiecents of the
          attenuation function. Currently returns 0, 0, and 0.


     FILES
          Link with -lDtOMio