Libre version of TDM

[wesp5]

8 minutes ago, datiswous said:

Why is this relevant?

I think it's just a matter of effort vs gain. If there are only a few hundred players using TDM under Windows, I doubt it would be worth the trouble to create a libre version for even fewer additional players. Which is probably the reason why none of the core developers are interested in this AFAIK...

Edited June 4, 2025 by wesp5

[datiswous]

Well the idea is to get more players in the Linux section because of that it can be distrubated in official Linux package managers. This is how most Linux users install software.

Although tdm already works fine in Linux using its official Linux installer.

[Fiver]

7 hours ago, wesp5 said:

If there are only a few hundred players using TDM under Windows

I think you bring up an interesting point here! It would definitely be interesting to learn some statistics.

• How many active players of TDM are there? ("Active"=plays at least once a month?)
• How many yearly downloads of the installers (Windows and Linux)?
• How many unique downloads of missions?
• How many unique visitors to the official webpage / wiki page / forum page / bugtracker?

[JackFarmer]

23 hours ago, Fiver said:

I think you bring up an interesting point here! It would definitely be interesting to learn some statistics.

• How many active players of TDM are there? ("Active"=plays at least once a month?)
• How many yearly downloads of the installers (Windows and Linux)?
• How many unique downloads of missions?
• How many unique visitors to the official webpage / wiki page / forum page / bugtracker?

That's an interesting set of questions I pose to myself on a regular basis. 

@nbohr1more Is there any data available regarding this?

[JackFarmer]

On 6/4/2025 at 2:03 PM, datiswous said:

Well the idea is to get more players in the Linux section because of that it can be distrubated in official Linux package managers. This is how most Linux users install software.

Although tdm already works fine in Linux using its official Linux installer.

I too think that the availability in the LM software manager might have had a positive effect.

[nbohr1more]

On 6/4/2025 at 3:24 PM, Fiver said:

I think you bring up an interesting point here! It would definitely be interesting to learn some statistics.

• How many active players of TDM are there? ("Active"=plays at least once a month?)
• How many yearly downloads of the installers (Windows and Linux)?
• How many unique downloads of missions?
• How many unique visitors to the official webpage / wiki page / forum page / bugtracker?

 

3 hours ago, JackFarmer said:

That's an interesting set of questions I pose to myself on a regular basis. 

@nbohr1more Is there any data available regarding this?

That's more of a question for @taaaki

[Fiver]

@whoozzem (and anyone else): What is your current best estimate of how much work (man days) it would require to make the necessary changes to

• The game data scripts
• Produce a minimal set of core assets (primarily GUI and HUD?)
• Anything else?

... to make a TDM-libre that can be used to play a minimal mission without any AI, that requires only lockpicks and optionally lantern and that otherwise contains all assets that it can (textures, sound etc)?

[whoozzem]

I personally still feel it's now a lost cause without first getting clarification over the licence for the def and script files from the original Doom 3, which is why, until such clarification is officially made I'm not doing anything further towards it.

I believe that while currently Microsoft may turn a blind eye to copy and pasted text from these files in TDM due to its' non-commercial nature, the moment it were to become Libre then the ability to use it commercially could lead to problems.

However to answer your question (bearing in mind I have a very limited knowledge of Doom 3/TDM modding other than what I learnt attempting to get a compiled cut-down version running). In terms of the game scripts the following are the only non-GPL header game scripts and you can comment them out from being loaded in source code:

• tdm_grandfather_clock.script
• tdm_turret.script
• tdm_audiograph.script
• tdm_camgoyle.script
• tdm_safe_lock.script
• tdm_safe.script

Also Grayman put the values as comments in code for these two files so they can be easily created:

tdm_soundprop.def
tdm_ai_base.def

It would be easier to seek out Greebo and Springheel and ask them to GPL their work since that would open up all the base def files without the task of re-creating them.

I suspect that it would take a very long time to recreate all the def files, also bear in mind that some functionality is copy/paste from Doom 3 eula protected files (func_static for example).

As regards the work done by Grayman, that would always remain NC-BY, however access to the SVN commits would allow you to diff remove his non-GPL edits from the .def files.

The UI function calls for TDM are all within the GPL source code, and as the UI is all a text based language it probably wouldn't take more than a couple of days to re-create a basic (though not pretty) UI.

There are many comments within the source code relating to the UI string references, so a relatively complete UI string language file can be re-created as well.

Edited June 10, 2025 by whoozzem

[Fiver]

22 hours ago, whoozzem said:

It would be easier to seek out Greebo and Springheel and ask them to GPL their work since that would open up all the base def files without the task of re-creating them.

@greebo, @Springheel: Would you consider licensing your work on the def files and script files in question as GPL?

[Guest]

11 hours ago, Fiver said:

@greebo, @Springheel: Would you consider licensing your work on the def files and script files in question as GPL?

If you wanna contact Springheel you gotta follow the process:

 

[datiswous]

1 hour ago, Airship-Ballet said:

If you wanna contact Springheel you gotta follow the process:

I think he can be contacted on Discord. Just be prepared to wait a bit maybe. Not sure about Greebo.

[Fiver]

5 hours ago, Airship-Ballet said:

If you wanna contact Springheel you gotta follow the process

Oh. As in an irreversibly final thing..?

In the case of @grayman, I perceived there were relatives, and in such cases the ownership of copyright could then be transferred (or additional licenses granted) by getting permission that way.

[Guest]

9 minutes ago, Fiver said:

Oh. As in an irreversibly final thing..?

In the case of @grayman, I perceived there were relatives, and in such cases the ownership of copyright could then be transferred (or additional licenses granted) by getting permission that way.

My legal team has advised that I clarify that was a joke about how difficult he might be to get a hold of and that he is in fact still of this Earth.

[vozka]

This seems like a futile process to me.

We all love TheDarkMod and tremendous work has been done on the engine, but I suspect that when developing a new project, especially commercial, almost everyone would rather go for a more modern engine because the reality is that stealth games are a relatively small niche and you need everything you can get to make people notice and buy your thing. TDM with its historical limits on polycounts (unless switching to lightmaps removed that?) and other features that we're used to and have no problem with but that are not exactly state of the art in my opinion just isn't "it", and it's only going to be less and less "it" over time, despite being a brilliant game on its own.

And making the game fully libre just so it can be included in certain distributions' free repos, while stripping out almost everything that makes TDM what it is, the community content, doesn't make sense to me either. If anything that could hurt its reputation because people who tried that wouldn't experience the actual game.

I only skimmed parts of the thread, have I missed a good reason to do this?

Also, another big issue that I think wasn't spelled out explicitly enough: I too thought that it would be awesome to have TDM on Steam. After looking into it, being educated by others and doing some searching I found out that TDM very likely contains a nontrivial amount of old content that may be seemingly re-licensed as CC-BY-NC, but legally cannot be, as its original license does not allow it.

I'm talking specifically about old textures.com content - it uses its own asset license that explicitly disallows being released as CC (because CC allows redistribution anywhere and textures.com license explicitly prohibits that). Yet some of those assets are a part of TDM, and it's likely that nobody knows for sure which ones and how many there are. Textures.com was at one point even recommended as a source to create assets on the wiki. So you may get permission from some old mission author who doesn't even remember that he did this, but his content can still be non-free and in fact infringing on its original license. Realistically nobody cares because there's no damage to textures.com being done (the textures are not being redistributed anywhere, they're "just" being incorrectly rebranded with a license that would allow it), but it makes the whole libre thing even more difficult. 

[demagogue]

Practically speaking, to get on to Steam you also need to formalize the team as a legal entity, which brings up stuff like tax filings, a board of directors and executives, reporting requirements, etc., that I think nobody was keen to take on or hand over to others to take on. To begin with, it'd change the whole character of the team & the project a lot, I think. I forgot the issues with GOG and Itch now. I think everybody admitted it sounds good in principle at least. It's just herding cats when you get into the details, and half the cats are missing. That's before you even get to the actual mess with all the licenses. 

---

I noticed in the credits of Blendo Game's Skin Deep, when I played it recently, that there's a credit for the TDM Engine, from which he evidently lifted some things for his game. Brendon has long been making his games with Doom engines, so there's a reason he did that. I'd say he's also a friend of the community. He's visited the forum & is known for his games & thinking on immersive sims.

But the point is that there's an example of someone branching off the TDM engine for a commercial project (that's also on Steam BTW). So if you have questions about it, that's someone you can contact to ask about it. I'm sure it matters that probably none of the assets carried over, though, only the game engine, or parts of it. 

[MirceaKitsune]

There's an interesting question with this, which if I'm not mistaken I approached in another thread long ago. I've considered making a big special project in TDM, which if I did I'd have wanted the option to distribute it as standalone: The idea was that the mission would be in the FM list like any other, but also packaged with a copy of TDM containing only the base pk4's the map uses. If this secondary distribution system were considered, I'm curious if there's be any issues with putting it in places like Itch or GoG or similar. Free of charge to respect the non-commercial licensing and wishes of the team in that regard, but I wonder if there's anything in the licensing that goes against posting your mission embedded in a copy of TDM.

[OrbWeaver]

You're free to distribute TDM yourself, in accordance with its license, along with a mission if desired (although I can't really see what you gain from doing so).

But I think getting it onto a platform like GoG is going to face the same problem that Steam did: they want a legal entity who can sign off on the license status and take legal responsibility for the distribution (in other words, an entity who can get sued instead of GoG themselves if there is a copyright dispute).

[wesp5]

2 hours ago, OrbWeaver said:

But I think getting it onto a platform like GoG is going to face the same problem that Steam did: they want a legal entity who can sign off on the license status and take legal responsibility for the distribution (in other words, an entity who can get sued instead of GoG themselves if there is a copyright dispute).

I'm not really sure about that. The version of Bloodlines GOG sells includes my patch already for a long time without me offering any kind of legal assistance or exact info about who helped me with it or whether it includes content from other creators. I believe they are willing to take the responsibility themselves in that case...

Edited June 20, 2025 by wesp5

[demagogue]

The official releases of System Shock 1 & 2 and Thief 1 & 2 also include fan patches in them.

Well typically these games have a clause buried in the license that they own modifications too, so that's gonna be the reason why, and they're going to quietly presume they own the whole thing without digging into it, which might not be really kosher, but nobody disputes it -- except I recall the maker of the SS2 patch Kolya was a little miffed that his patch was put into the commercial release, or rather that they restricted it's use outside of the product while integrating it, since he wanted to keep it freely available & not to make a company money, although he granted that they had the legal right to do it. 

TDM is a little special just because it's a non-commercial game, idTech4 was open sourced, or anyway GPL'd, and about the only thing we restrict is that assets are under a CC license. The disputes we sometimes get aren't really about the license so much as tact & courtesy, e.g., to not recycle or change someone else's map as one's own, or at least you should get their consent first. 

[Guest]

13 hours ago, OrbWeaver said:

You're free to distribute TDM yourself, in accordance with its license, along with a mission if desired (although I can't really see what you gain from doing so).

I can think of a scenario, where you are working on a mission for several years, rather than months, and since TDM updates add and remove things, and also break features that were already working, you might want to stick to a version that you liked best. But in that scenario, you'd just need to know which stock TDM files are absolutely necessary to run your mission, so you can delete the rest. That would change on a mission basis though.

Edit: I mean, it's either that, or asking people to downgrade, so it's kinda tricky choice.

Edited June 21, 2025 by Guest