Source code for Commander Keen: Keen Dreams
by Kasper Tidemann
I have fond memories of playing DOS-based games back in the day, including the fabled Commander Keen series. And now, it appears the source code for Commander Keen: Keen Dreams has been released.
Supposedly, the code is designed for Borland C++ 2.0, the 1991 version of the compiler. While I have yet to attempt to compile it myself, reading through the source code and understanding how the developers implemented gravity, friction and so on is quite fun. The source code is available on GitHub.