Mark 4 Open Inventor NAG Graphical Interface 
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1. Interface files

   Open Inventor is written in C++, while the NAG Graphics Library is
   a collection of Fortran routines. As such, the Open Inventor NAG
   Graphical Interface consists of a number of Fortran files, and a
   C++ file which deals with calls to the Open Inventor functions.

   Two versions of the interface are provided; for unix systems, and
   PCs using the Microsoft compilers. The main difference lies in the
   fact that a special interface block is required in the Fortran
   code, for C and C++ routines called from the Fortran code. Also,
   the SceneViewer option is not implemented for the PC version of the
   interface.

   The following files are required for the interface on a unix
   system:
   
   *.f
   invent.C
   nag.h
   
   For the PC version the following files are needed:

   *.for
   *.f (except j06wdf.f, j06wzf.f, j06xlf.f j06ycx.f, j06yhf.f,
       j06ynf.f, j06zhm.f, nagiv.f)
   invent.cxx

2. Sample makefile

   A sample make system is provided for the unix version of the
   interface only. It consists of the following files:

   make_iv
   langopts
   makefile

3. Documentation

   README     - this text

   un         - Interface Usage Document
   figure1.iv - Figure 1 of the Interfaces Usage Document
   figure2.iv - Figure 2 of the Interfaces Usage Document

   in         - Installers' Note