I have a file with extension .tnt . This is a file that is used by an 
appropriate viewer to produce a "3d image" on a 2D screen without 
augmentation (goggles, etc.). Is there either a viewer that can render 
tnt files, or a converter that will convert a tnt file to a more common 
3d image file format?  If there is no Linux application that can handle 
a .tnt in any form, is there a MS Win application for this purpose (I 
would run this under a MS Win 10 virtual machine under Linux)?

I am attempting to contact the author/s of a paper that has 
supplementary data visualised in a tnt file, but as I have a copy of the 
tnt file, it would be simpler to work from that file.  From 
https://urldefense.proofpoint.com/v2/url?u=https-3A__filext.com_file-2Dextension_TNT&d=DwICaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=gd8BzeSQcySVxr0gDWSEbN-P-pgDXkdyCtaMqdCgPPdW1cyL5RIpaIYrCn8C5x2A&m=vZPJ5vQonpV4zw0gVVizWaBi3CSOOONmr_IHJLMRM2U&s=wVLAYxEYuqenEv7b0XY86uRib26Cpvo9AgpGkzggVeU&e= 

The TNT file type is primarily associated with TurnTool by TurnTool ApS. 
Interactive Realtime Web 3D. Realtime 3D graphics solution targeted at 
the growing market for interactive 3D on the Internet. TurnTool is 
running a contest through 4 April 2005. Submit your models.  End excerpt

Note that the above is rather dated (one of the reasons I am never 
enthusiastic about proprietary encoding formats is that once obsolete 
and not well disseminated, it may be next to impossible to decode); I 
have attempted to locate TurnTool ApS but it appears to be defunct.

If anyone has a converter from tnt to a more readily supported format, I 
will be willing to provide the tnt file for conversion as the work is 
published (not under NDA).

Take care.  Stay safe.