The horrendous interface is likely a symptom of the poor quality of the codebase he developed for Dwarf Fortress.
Look at his other projects, such as Liberal Crime Squad (http://www.bay12games.com/lcs/). The code for LCS available on that site is atrocious. I know, because I helped to convert the 38K lines (yes 38 THOUSAND LINES) of code in a SINGLE C++ FILE into something that is actually maintainable when he open sourced the game (fun fact: the IDE I used back then would crash when opening that file).
The reason for this is clear, like you say, Tarn comes from a physics/math background. He does not seem to be very experienced at software engineering (at least he wasn't 9 years ago when LCS was open-sourced). I would not be surprised if the Dwarf Fortress codebase is just as inscrutable as the resulting game.
Look at his other projects, such as Liberal Crime Squad (http://www.bay12games.com/lcs/). The code for LCS available on that site is atrocious. I know, because I helped to convert the 38K lines (yes 38 THOUSAND LINES) of code in a SINGLE C++ FILE into something that is actually maintainable when he open sourced the game (fun fact: the IDE I used back then would crash when opening that file).
The reason for this is clear, like you say, Tarn comes from a physics/math background. He does not seem to be very experienced at software engineering (at least he wasn't 9 years ago when LCS was open-sourced). I would not be surprised if the Dwarf Fortress codebase is just as inscrutable as the resulting game.