Eureka is a cross-platform map editor for the classic DOOM games. It started as a fork of the Yadex editor attempting to make it use the FLTK GUI toolkit and implement multiple Undo / Redo.
Supported games include DOOM, DOOM 2, Final Doom, FreeDoom, HacX and Heretic. Supported source ports are Boom, EDGE, Doom Legacy and Odamex.