if you can't port DP to hexen2, try porting hexen2 to DP?

I really wonder how plausable it would be...
fteqcc -Kthinktime should compile hexenc code to a format that DP can run. However, you'll still need to replace the defs.qc, the builtins, and (m)any extended writebytes. Many of the hexen2 'extensions' are available in some form in DP, though eg in the case of tracebox, the arguments are in a different order. You can use #define or just wrappers to fix those.
You could always just try running FTE as a server with DP as a client. FTE will strip out any network extensions the client doesn't support, but it should otherwise run, assuming you patch DP to accept h2 bsps first. If I remember correctly, a hack-fix is a 1-liner, just change the number of hulls for a v29 bsp to 8 instead of 4 and you should be able to at least view the maps. I've not tested how much will work beyond that as DP started locking up upon connect, a DP bug which I believe has now been fixed.
Either way, the real problem is the lack of bumpmaps+specular maps+rtlights files for hexen2, without those all you'd get is a few extra shadows and a 20th of the framerate.
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