Utilize 3D_Graphics_File_Conversions for import

[jumpjack]

Found the C source code for ivconv, decoder for some very old formats such .iv (Silicon Graphics Inventor):

https://github.com/rich-hart/3D_Graphics_File_Conversions

C++: http://web.archive.org/web/20120104203132/http://people.sc.fsu.edu/~jburkardt/cpp_src/ivcon/ivcon.cpp

".3ds" 3D Studio Max binary;\n"; ".ase" 3D Studio Max ASCII export;\n"; ".byu" Movie.BYU surface geometry;\n"; ".dxf" DXF;\n"; ".gmod" Golgotha model;\n"; ".hrc" SoftImage hierarchy;\n"; ".iv" SGI Open Inventor;\n"; ".obj" WaveFront Advanced Visualizer;\n"; ".off" GEOMVIEW Object File Format;\n"; ".pov" Persistence of Vision (output only);\n"; ".smf" Michael Garland's format;\n"; ".stl" ASCII StereoLithography;\n"; ".stla" ASCII StereoLithography;\n"; ".stlb" Binary StereoLithography;\n"; ".tec" TECPLOT (output only);\n"; ".tri" [Greg Hood ASCII triangle format];\n"; ".tria" [Greg Hood ASCII triangle format];\n"; ".trib" [Greg Hood binary triangle format];\n"; ".txt" Text (output only);\n"; ".ucd" AVS UCD file(output only);\n"; ".vla" VLA;\n"; ".wrl" VRML (Virtual Reality Modeling Language) (output only).\n"; ".xgl" XML/OpenGL format (output only);\n";