emulator: RigelEngine
type: standalone
core_classification: game_engine
source: "https://github.com/lethal-guitar/RigelEngine"
upstream: "https://github.com/lethal-guitar/RigelEngine"
profiled_date: "2026-10-22"
source_commit: "30afeff8f0b105eac77ee0a2fbd54b06e1a49b60"
core_version: "0.9.1-28-g30afeff8"
display_name: "Duke Nukem II (RigelEngine)"
cores: [rigelengine]
systems: [duke-nukem-2]
verification: existence

notes: |
  Reimplementation of the Duke Nukem II engine (Apogee, 1993). It plays the
  data files of the DOS release, shareware or registered.

  Game path. The path comes from the positional command line argument
  (src/main.cpp:222), else the working directory when it holds NUKEM2.CMP,
  else a folder browser (src/game_main.cpp:101-125). A folder is accepted only
  when NUKEM2.CMP exists in it (src/game_main.cpp:72-78, 136-142) and the
  choice is kept in the user profile (src/game_main.cpp:152-153, 235-240).
  File names are opened as written, in upper case.

  NUKEM2.CMP is an archive with a dictionary of 12-character names, offsets
  and sizes. Every game asset is read from it (src/assets/resource_loader.cpp:148,
  515-537). The only check is that each entry lies inside the file
  (src/assets/cmp_file_package.cpp:43-66). No size, CRC or hash is compared.

  Shareware or registered. The registered set is assumed when the archive
  holds LCR.MNI and O1.MNI (src/frontend/game.cpp:235-245). With the
  shareware set, episodes 2 to 4 answer with the ordering message
  (src/frontend/menu_mode.cpp:243-247) and saves of those episodes are
  refused (src/frontend/menu_mode.cpp:303-305). The shareware episode plays
  in full.

  Intro movies. NUKEM2.F1 to NUKEM2.F4 are loaded loose from the game path
  (src/assets/resource_loader.cpp:415-429) when the intro is built
  (src/ui/intro_movie.cpp:72, 80, 94, 108), and NUKEM2.F5 is the Apogee logo
  (src/ui/apogee_logo.cpp:63-67). A missing file throws and the intro or the
  logo is skipped (src/frontend/intro_demo_loop_mode.cpp:38-55, 64-77).

  On first launch the original game's saves, high scores and settings
  (NUKEM2.-NM, NUKEM2.-S1 to -S8, NUKEM2.-V1 to -V4, NUKEM2.-GT) are imported
  when present (src/assets/user_profile_import.cpp:144-203). They are user
  data, not distributed files.

  The shareware release that the project points to is
  archive.org msdos_DUKE2_shareware, DUKE2.zip (README.md:82,
  cmake/rigel_pack.cmake:14-17). It holds NUKEM2.CMP and all five movies.
  NUKEM2.EXE in that release is never opened.

  EmuELEC 4.8 builds commit f05996f9b3ad3b3ea5bb818e49e7977636746343, where
  every file cited above is identical, and passes /storage/roms/ports/rigelengine
  as the game path.

files:
  - name: "NUKEM2.CMP"
    category: game_data
    system: duke-nukem-2
    required: true
    description: "Game data archive: levels, graphics, sounds, music and texts"
    note: "Its presence validates the game path. The shareware archive plays episode 1, the registered one all four."
    source_ref: "src/game_main.cpp:72-78, 136-142, src/assets/resource_loader.cpp:148"

  - name: "NUKEM2.F1"
    category: game_data
    system: duke-nukem-2
    required: false
    description: "Intro movie, shot at the shooting range"
    note: "The intro needs F1 to F4 together, it is skipped when one is missing"
    source_ref: "src/ui/intro_movie.cpp:80, src/frontend/intro_demo_loop_mode.cpp:38-44"

  - name: "NUKEM2.F2"
    category: game_data
    system: duke-nukem-2
    required: false
    description: "Intro movie, Neo LA opening scene"
    note: "The intro needs F1 to F4 together, it is skipped when one is missing"
    source_ref: "src/ui/intro_movie.cpp:72, src/frontend/intro_demo_loop_mode.cpp:38-44"

  - name: "NUKEM2.F3"
    category: game_data
    system: duke-nukem-2
    required: false
    description: "Intro movie, target hit"
    note: "The intro needs F1 to F4 together, it is skipped when one is missing"
    source_ref: "src/ui/intro_movie.cpp:94, src/frontend/intro_demo_loop_mode.cpp:38-44"

  - name: "NUKEM2.F4"
    category: game_data
    system: duke-nukem-2
    required: false
    description: "Intro movie, end of the shooting range scene"
    note: "The intro needs F1 to F4 together, it is skipped when one is missing"
    source_ref: "src/ui/intro_movie.cpp:108, src/frontend/intro_demo_loop_mode.cpp:38-44"

  - name: "NUKEM2.F5"
    category: game_data
    system: duke-nukem-2
    required: false
    description: "Apogee logo movie"
    note: "The logo is skipped when the file is missing"
    source_ref: "src/ui/apogee_logo.cpp:63-67, src/frontend/intro_demo_loop_mode.cpp:49-55, 64-70"