emulator: boom3
type: libretro
core_classification: game_engine
source: "https://github.com/libretro/boom3"
upstream: "https://github.com/dhewm/dhewm3"
profiled_date: "2026-03-23"
source_commit: "efe140ce8fdf8793f5a6fbba062fb34df7f55a81"
upstream_commit: "455b88e8dff2be822f08eb498f51b383e851fa38"
core_version: "git"
display_name: "Doom 3 (boom3)"
cores: [boom3, boom3_xp]
systems: [doom3]
verification: existence
notes: >
  Doom 3 source port based on dhewm3 (GPL Doom 3 engine). The core accepts
  .pk4 extensions (retro_get_system_info sets valid_extensions = "pk4").
  Content is loaded directly from the .pk4 file path - the engine extracts
  the grandparent directory as fs_basepath (neo/sys/libretro/libretro.cpp:4242,4310-4311
  via extract_directory called twice on info->path) and expects the standard
  Doom 3 directory layout with base/ containing pak000.pk4 through pak008.pk4.
  BASE_GAMEDIR is "base" (neo/framework/Licensee.h:58), and content in a
  directory under another name is mounted in its place through fs_gamedirname
  (neo/sys/libretro/libretro.cpp:3248-3262). One binary serves both
  games: content in a directory named d3xp, or the doom_game core option,
  passes "+set fs_game d3xp" (neo/sys/libretro/libretro.cpp:3238-3246,4245-4271) to load the
  Resurrection of Evil expansion from a d3xp/ subdirectory alongside base/.
  The filesystem code (neo/framework/FileSystem.cpp:2318)
  scans for .pk4 files in the game directory and loads them in order, with
  higher-numbered paks overriding lower ones. The core requires OpenGL
  (RETRO_ENVIRONMENT_SET_HW_RENDER) and XRGB8888 pixel format. The game
  data is the commercial Doom 3 release, not engine firmware. No BIOS or
  system files are needed in the RetroArch system directory.

  Builds made with HAVE_VR=1 (the Windows x64, Linux x64 and Linux arm64
  jobs, .gitlab-ci.yml:87, 101, 109) offer the boom3_vr_enable option. With it
  on, the core passes "+set fs_vr 1" and the filesystem mounts base_vr/ over
  base/ and d3xp_vr/ over d3xp/ (neo/sys/libretro/libretro.cpp:3264-3272,
  neo/framework/FileSystem.cpp:2440-2472). These replacement packs carry the
  hand and weapon models of Doom3Quest and ship in the core's repository under
  tools/vr_paks/compiled.

files:
  - name: "pak399.pk4"
    path: "base_vr/pak399.pk4"
    system: doom3
    category: game_data
    load_from: content_dir
    required: false
    description: "VR hand and weapon models (Doom3Quest), mounted over base/"
    source_ref: "neo/sys/libretro/libretro.cpp:4313-4335, neo/framework/FileSystem.cpp:2440-2450"
    note: "Read in VR builds with boom3_vr_enable on. base_vr/ sits beside base/, one level above the loaded .pk4. When the file is absent the core shows a notification and the game still starts."

  - name: "pak399roe.pk4"
    path: "d3xp_vr/pak399roe.pk4"
    system: doom3
    category: game_data
    load_from: content_dir
    required: false
    description: "VR replacement pack for Resurrection of Evil, mounted over d3xp/"
    source_ref: "neo/framework/FileSystem.cpp:2465-2472"
    note: "Mounted in VR builds when fs_game is d3xp. The code reads every .pk4 in d3xp_vr/ and names none, this is the pack the core's repository ships for it."