ZDoom CLASSIC 2.1.4a, a fork of ZDoom 2.1.4 (https://github.com/rheit/zdoom) compiled for pentium machines. Includes a new quad horizontally and double vertically low detail mode from ZDOOM LE as well as pixel doubled and quadrupled lowres directdraw modes from ZDoom 2.3.
Compiles with CodeBlocks 16.01, TDM-GCC 4.6.1 and NASM 0.99.06. You'll need the following libraries: dx9mgw.zip and fmodapi375win.zip. A project for CodeBlocks is included, however version 16.01 is very buggy and you'd need to edit the project manually. You could try later versions or 12.11. You'll need to use the included makefile in wadsrc to generate zdoom.pk3.
Some notes:
- Compiling with TDM-GCC 4.9.2 the exe would require Windows 98 to run and the compiler is slower. GCC 3.4 (MinGW 3.4.2) also works and it's even faster (untested with GZDoom).
- Precompiled FLAC and Zlib libraries are also included.
You can follow the following guide: https://zdoom.org/wiki/Compile_ZDoom_on_Windows