dhewm3.org

dhewm3 is a source port of the original Doom3 — not Doom3 BFG. It runs the same game you already own, but on a modernized engine that fixes long-standing bugs, adds 64-bit support, improves widescreen handling, and brings EAX-like sound effects to every supported platform. You still need to legally own Doom3 and supply its game data; dhewm3 itself does not include the game.

What dhewm3 actually is

A source port takes released game source code and rebuilds it to run on current hardware and operating systems. dhewm3 does this for the original Doom3 codebase (which id Software released under the GPL). It is not a remake, not a new game, and not a port of Doom3 BFG — the project page explicitly points BFG owners toward Chocolate DOOM-3-BFG instead.

Because the engine code is separate from the game assets, dhewm3 ships as an executable plus support files. The Doom3 data (maps, textures, sounds, scripts) comes from your own installation.

What it improves over the original Doom3

The 1.5.5 release also removed several sources of microstutter, including the old 60 vs 62.5 fps problem, so the game runs smoother — especially with VSync enabled.

Platform support

dhewm3 is known to work on:

• Windows
• Linux
• macOS
• FreeBSD
• OpenBSD
• AROS

The project states it should work on, or be easily portable to, any system supporting OpenGL 1.4 with ARB shaders, SDL, and OpenAL.

Mod compatibility — read this before installing mods

dhewm3 only supports old mods if they either:

• don't require their own game DLL, or
• have been ported to dhewm3.

Mods that ship their own compiled game DLL for the original Doom3 engine will not work unmodified. The project maintains a Mods page and a dhewm3-mods repository with DLLs for selected mods.

What you need to play

1. A legally owned copy of Doom3.
2. The Doom3 game data files from that copy.
3. A dhewm3 executable for your platform.
4. Optionally, the widescreen GUI files (dhewm3-wide-guis-*.zip) if you want properly scaled interfaces for the base game, Resurrection of Evil, or The Lost Mission.

The project page is clear on the licensing split: the source code is GPL, but the game data is not, so owning the game remains a requirement.

Where to get it

• Executables: the project's GitHub releases, including Windows and 64-bit Linux builds.
• macOS: a signed and notarized build is published at Mac Source Ports.
• Game data: from your own Doom3 installation — see the project's How to Install section.

If you own Doom3 (not BFG) and want it to run cleanly on a modern 64-bit system with working widescreen and cross-platform sound effects, dhewm3 is the straightforward choice. If you own Doom3 BFG instead, look at Chocolate DOOM-3-BFG.

dhewm3 1.5.5 is a source port update that focuses on smoother frame pacing, widescreen UI support, and a newer texture compression format. If you already run dhewm3, this release is mainly about fixing microstutter and enabling higher-quality retexture packs; if you are installing fresh, you still need to legally own Doom3 and supply its game data separately.

Smoother frame pacing

The headline change is the removal of several sources of microstutter, including the long-standing 60 vs 62.5fps problem. According to the project page, the game should now run smoother than before, especially when VSync is enabled.

This matters because VSync previously interacted badly with Doom3's internal timing, producing small hitches even on hardware that could hold a steady frame rate. If you had given up on VSync in dhewm3, 1.5.5 is the version to retest.

Widescreen GUI support

dhewm3 1.5.5 adds support for widescreen GUIs. This is not automatic: it requires adjusting the .ui files.

To make it easy, Arl created updated .ui files for:

• the base game
• Resurrection of Evil
• The Lost Mission

These are offered as an optional download (dhewm3-wide-guis-*.zip). If you play on a widescreen monitor and want the HUD and menus to lay out correctly, install the matching package for the campaigns you own.

BC7 (BPTC) .dds texture support

dhewm3 now supports BC7-compressed (BPTC) .dds textures. Compared with the older S3TC/DXT/BC1-3 standard that Doom3 always supported, BC7 offers better quality at the same size as DXT3-5.

That makes it useful for high-resolution retexturing packs, where compression artifacts are more visible. The first texture pack to use this feature is hidef2k by y2keeth.

Mod-related updates in this release

The project also notes changes on the mods side:

• dhewm3-mods now has DLLs for new mods: ELDOOM, Grimm, HeXen: Edge Of Chaos Demo, and Real Gibs. For Real Gibs, the mod page states it only works with the 32-bit version of dhewm3 — but that refers to the realgibs.dll they ship. You can use their gamedata with the .dll/.so provided by dhewm3-mods, or build the library yourself.
• Blood Mod has been updated to v1.8 and now also supports Resurrection Of Evil.
• LibreCoop is now maintained as part of dhewm3-sdk until upstream becomes active again.

Getting the build

dhewm3 1.5.5 is available for download at GitHub, including builds for Windows and 64-bit Linux. As usual, a signed and notarized build for macOS can be found at Mac Source Ports.

What hasn't changed

Two constraints from earlier versions still apply:

• dhewm3 is a source port of the original Doom3, not Doom3 BFG. For BFG, the project points to Chocolate DOOM-3-BFG.
• The Doom3 source code is GPL, but you still need to legally own the game and provide dhewm3 with the game data to play.

It also only supports old mods if they either don't require their own game DLL or have been ported to dhewm3 — check the Mods page for the current list.

dhewm3 only runs old Doom3 mods if they either don't ship their own game DLL or have been ported to dhewm3. Mods that rely on a custom game DLL built for the original Doom3 executable will not load unless someone has recompiled that DLL for dhewm3. For newer mods, the dhewm3-mods project provides compatible DLLs for a handful of titles, so the practical answer is: check the Mods page first, then check dhewm3-mods for a prebuilt library.

The compatibility rule

The dhewm3 project page states it plainly: dhewm3 "only supports old Mods if they either don't require their own game DLL or have been ported to dhewm3."

That splits mods into three groups:

• No custom game DLL — these are pure asset/content mods (maps, textures, sounds, defs, GUIs). They generally work because dhewm3 supplies the engine and game logic itself.
• Custom game DLL, already ported — the mod author or a third party has rebuilt the DLL against the dhewm3 SDK. These work.
• Custom game DLL, not ported — the mod ships a binary compiled for the original Doom3. dhewm3 cannot load it, so the mod won't run.

The reason is that a game DLL is compiled against a specific engine's interface. dhewm3 is a source port with its own build of that interface, so an original Doom3 DLL is not binary-compatible.

Mods with DLLs provided by dhewm3-mods

The dhewm3-mods repository supplies DLLs for several newer mods, so you can use their game data with a dhewm3-compatible library instead of the one they ship:

The Real Gibs entry is the clearest example of the 32-bit caveat: the mod's own instructions assume a 32-bit build, but the restriction applies to the DLL they bundle, not to dhewm3 as a whole. Swapping in the matching library from dhewm3-mods (or compiling it yourself) is the workaround.

How to check a mod before installing

1. Look at what the mod ships. If there is no .dll/.so game library in the package, it is likely a content-only mod and should load.
2. If it does ship a game DLL, check the dhewm3 Mods page for that mod's name.
3. If it isn't listed there, check dhewm3-mods for a prebuilt library.
4. If neither has it, the mod needs to be ported — either by its author or by building the library against the dhewm3 SDK yourself.

Practical caveats

• Match the library to your build. A 32-bit DLL won't load in a 64-bit dhewm3, and vice versa. Use the .dll on Windows and the .so on Linux, matching your architecture.
• Game data is still required. dhewm3 is a source port, not a standalone game. You still need to legally own Doom3 and provide the game data, as noted on the project page.
• The Mods page is the source of truth. Compatibility changes as mods get ported and as dhewm3-mods adds libraries, so check it rather than relying on a fixed list.

If your mod isn't covered anywhere, the fallback is to build its game library against the dhewm3 SDK — that is the same route the ported mods took.

dhewm3 is known to run on Windows, Linux, macOS, FreeBSD, OpenBSD, and AROS, and it should work on (or be easily portable to) any system that supports OpenGL 1.4 with ARB shaders, SDL, and OpenAL. If your machine meets those three library requirements, dhewm3 is very likely to build and run there. Separately, you still need to legally own Doom3 and supply its game data — the engine alone won't start a game.

Supported platforms

The project lists these as known-working targets:

Beyond that list, dhewm3 "should work on (or be easily portable to) any system that supports OpenGL 1.4 with ARB shaders, SDL and OpenAL." In other words, the platform list isn't a hard ceiling — it's a record of what's been confirmed. A system with the right graphics, input/windowing, and audio libraries is a reasonable porting candidate.

The actual technical requirements

Three dependencies define compatibility:

• OpenGL 1.4 with ARB shaders — the rendering baseline. This is a relatively old OpenGL level, so most hardware from the mid-2000s onward qualifies. The ARB shader extension is the part to check, not just the OpenGL version number.
• SDL — handles windowing, input, and platform glue.
• OpenAL — audio output. dhewm3 uses OpenAL Soft's EFX support to provide EAX-like sound effects on all operating systems and hardware, rather than relying on platform-specific audio paths.

If a platform provides these three, the porting effort is described as easy rather than a rewrite.

64-bit support

dhewm3 has 64-bit support, which the original Doom3 release did not. The 1.5.5 release notes specifically mention builds for Windows and 64-bit Linux, with a signed and notarized macOS build available via Mac Source Ports. So on the major desktop platforms you can run a native 64-bit binary rather than being limited to 32-bit.

What dhewm3 is not

dhewm3 is a source port of the original Doom3, not Doom3 BFG Edition. For BFG, the project points elsewhere (Chocolate DOOM-3-BFG). This matters when checking requirements, because BFG has different data and engine assumptions.

Mod compatibility is a separate requirement

Meeting the system requirements doesn't guarantee every mod runs. dhewm3 only supports old mods if they either don't require their own game DLL or have been ported to dhewm3. Mods shipping their own compiled game logic need a dhewm3-compatible build of that library. The project maintains DLLs for some newer mods, and notes cases like Real Gibs, where the shipped realgibs.dll is 32-bit only — you'd use their game data with the .dll/.so provided by dhewm3-mods instead, or build the library yourself.

Practical takeaway

• On Windows, Linux, macOS, FreeBSD, OpenBSD, or AROS: expect it to work; grab a build for your platform.
• On another OS: check for OpenGL 1.4 + ARB shaders, SDL, and OpenAL. If all three are present, it's a viable port target.
• In all cases: you must own Doom3 legally and provide the game data — the port ships the engine, not the game.
• For mods: verify the mod either has no custom game DLL or has been ported to dhewm3 before assuming it will load.

dhewm3 is a source port of the original Doom3 (not Doom3 BFG), and installing it takes two separate pieces: the dhewm3 executables, which you download for free, and the Doom3 game data, which you must supply from a copy of the game you legally own. The dhewm3 project states plainly that while the Doom3 source code is released under the GPL, "you still need to legally own the game and provide dhewm3 the game data to play." So the install is really two tasks: get the engine, then point it at your own game files.

What dhewm3 is (and isn't)

dhewm3 is a source port of the original Doom3, not Doom3 BFG. If you want a BFG Edition port, the project points elsewhere (Chocolate DOOM-3-BFG). Compared with the original Doom3, dhewm3 adds many bugfixes, EAX-like sound effects on all operating systems and hardware via OpenAL Soft's EFX support, much better widescreen resolution support, 64-bit support, and a mod-independent Settings Menu.

One compatibility caveat matters before you start: dhewm3 "only supports old Mods if they either don't require their own game DLL or have been ported to dhewm3." If you plan to run a specific old mod, check the Mods page first.

Step 1: Get the dhewm3 executables

Download the engine from the project's GitHub releases. The current release noted on the site is dhewm3 1.5.5 (dated 2026-06-08), and the GitHub download includes builds for Windows and 64-bit Linux.

For macOS, use the signed and notarized build hosted at Mac Source Ports rather than the GitHub archive.

Platform summary:

The project is known to work on Windows, Linux, macOS, FreeBSD, OpenBSD, and AROS. More generally, it should work on — or be easily portable to — any system that supports OpenGL 1.4 with ARB shaders, SDL, and OpenAL. If your platform isn't in the known list, those three requirements are the things to check.

Step 2: Provide the Doom3 game data

dhewm3 does not ship the game. You need to legally own Doom3 and give dhewm3 the game data. The project's own "Getting the Doom3 Game Data" and "How to Install" sections cover the specifics of which files are needed and where they go; follow those rather than guessing at file layouts, since the exact required data files depend on your copy of the game.

The practical sequence:

1. Install or locate your legally owned copy of Doom3.
2. Collect the game data files from it as described in the project's install instructions.
3. Place them where dhewm3 expects them.
4. Launch dhewm3 and confirm it finds the data.

If dhewm3 starts but can't find the game data, the problem is almost always step 2 or 3 — the engine itself installed fine, but the data path or file set is wrong.

Optional extras worth knowing about

• Widescreen GUIs: dhewm3 1.5.5 added support for widescreen GUIs, but it requires adjusting the .ui files. Arl created versions for the base game, Resurrection of Evil, and The Lost Mission, offered as an optional download (dhewm3-wide-guis-*.zip).
• BC7-compressed textures: dhewm3 now supports BC7-compressed (BPTC) .dds textures, which offer better quality than the older S3TC/DXT/BC1-3 standard at the same size as DXT3-5. This is aimed at high-res retexturing packs; the first pack to use it is hidef2k by y2keeth.
• Smoother framerate: 1.5.5 removed several sources of microstutter (including the old 60 vs 62.5fps problem), so the game should run smoother, especially with VSync.
• Mod DLLs: dhewm3-mods provides DLLs for some newer mods, including ELDOOM, Grimm, HeXen: Edge Of Chaos Demo, and Real Gibs. Note that the Real Gibs page says it only works with the 32-bit version of dhewm3, but that refers to the realgibs.dll they ship — you can use their gamedata with the .dll/.so provided on dhewm3-mods, or build the library yourself. Blood Mod has been updated to v1.8 and now also supports Resurrection of Evil, and LibreCoop is now maintained as part of dhewm3-sdk.

Common sticking points

• Expecting the download to include the game. It doesn't. The engine is free; the data is not.
• Using the wrong macOS build. Grab the signed/notarized one from Mac Source Ports.
• Assuming old mods just work. They only work if they don't need their own game DLL or have been ported to dhewm3.
• Skipping the install docs. The "How to Install" section is the authoritative source for where the game data goes on your platform.