Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 6:03 am

I saw a mod something looks like standalone is going to be commercial. AFAIK, ZDoom and GZDoom licensed under GPL v3. So shouldn't be all source codes must be distributed as GPL v3 as well?

And the term "source code" in here, what exactly, meaning of? Is this meaning of includes all action scripts, or just original source codes of ZDoom/GZDoom? Or not just scripts, includes all graphics and musics as well?

And last, what happens with license about original doom related resources? Even the mod doesn't contain any classic Doom resource, I think it's still be related, because the program was designed for running Doom.

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 6:17 am

I've seen this asked numerous times, and the answer every time is "yes". As long as you use a version post-GPL-ification, preferably after the resource split too. (So 3.5.0 should be just fine)

And last, what happens with license about original doom related resources? Even the mod doesn't contain any classic Doom resource, I think it's still be related, because the program was designed for running Doom.

Remove zd_extra.pk3, that's the non-GPL stuff you don't want to give out.

And the term "source code" in here, what exactly, meaning of? Is this meaning of includes all action scripts, or just original source codes of ZDoom/GZDoom? Or not just scripts, includes all graphics and musics as well?

If you make any modifications to the GZDoom source code and publish the executable in your game, you MUST publish your changes! That is one of the core GPL principles, and the reason why GZDoom went GPL was to enforce the idea of "if you take something, then give back something else".

You do not need to publish your ACS source code. But I will be honest: It looks better if you do. It's not a requirement, just an encouragement.

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 7:20 am

Ok, thanks for quick response. However I have some more questions from your answers.

Rachael wrote:As long as you use a version post-GPL-ification, preferably after the resource split too. (So 3.5.0 should be just fine)


What if under 3.5.0? I found the information that license was changed when 3.0 released under GPL license. Is is ok any version between 3.0 and 3.5.0?

Rachael wrote:If you make any modifications to the GZDoom source code and publish the executable in your game, you MUST publish your changes!


That modification also includes change icon or text for display? Like printing other game name instead of Doom or GZDoom? If do, where should I publish my changes?

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 7:36 am

Github is the best place to publish your changes.

Any version 3.2.0 and up should be legal, GPL-wise, as long as you remove zd_extra.pk3, but I would urge you to consider 3.5.0 or a dev build due to security flaws with past versions.

I would never condone encouraging any author to use a version of GZDoom that has known exploitation vectors.

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 9:37 am

A better question would be: Does your game deserve to be sold for money?

There are hundreds if not thousands of free mods and even TCs for Zdoom, and many are still being made. If you want me to pay for your Zdoom based game then it better be very high quality. Unless you are a very skilled sprite artist and a top notch level designer I can't see this happening. And even if you are, making such a game all by yourself would take years even if you invested many hours into making it almost every single day. So even if you did/do have the skill, you would still probably not be able to actually finish it unless you were extremely dedicated. Don't take this personally, just being honest.

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 10:47 am

hardcore_gamer wrote:A better question would be: Does your game deserve to be sold for money?

There are hundreds if not thousands of free mods and even TCs for Zdoom, and many are still being made. If you want me to pay for your Zdoom based game then it better be very high quality. Unless you are a very skilled sprite artist and a top notch level designer I can't see this happening. And even if you are, making such a game all by yourself would take years even if you invested many hours into making it almost every single day. So even if you did/do have the skill, you would still probably not be able to actually finish it unless you were extremely dedicated. Don't take this personally, just being honest.

So maybe nobody should ever make anything, ever again, because there's free things that are good.

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 11:17 am

Rachael wrote:I've seen this asked numerous times, and the answer every time is "yes". As long as you use a version post-GPL-ification, preferably after the resource split too. (So 3.5.0 should be just fine)

And last, what happens with license about original doom related resources? Even the mod doesn't contain any classic Doom resource, I think it's still be related, because the program was designed for running Doom.

Remove zd_extra.pk3, that's the non-GPL stuff you don't want to give out.

Huh that's useful to know, I had no idea about zd_extra.pk3

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 11:52 am

wildweasel wrote:
hardcore_gamer wrote:A better question would be: Does your game deserve to be sold for money?

There are hundreds if not thousands of free mods and even TCs for Zdoom, and many are still being made. If you want me to pay for your Zdoom based game then it better be very high quality. Unless you are a very skilled sprite artist and a top notch level designer I can't see this happening. And even if you are, making such a game all by yourself would take years even if you invested many hours into making it almost every single day. So even if you did/do have the skill, you would still probably not be able to actually finish it unless you were extremely dedicated. Don't take this personally, just being honest.

So maybe nobody should ever make anything, ever again, because there's free things that are good.


No, my point was that once you start charging money for something you can't hold it to the same standard as you would if it were released as a free mod. That means that unless you are really skilled at what you do (as in, more skilled than 90+% of the modding community) it makes no sense to charge money for your work. I don't remember the name of the game but some time ago I saw somebody over at the doomworld forums advertise their intended commercial doom engine game. It was this mediocre looking alien game which used poorly animated 3D models. As a free mod it could have been some harmless fun that might have been fun to play for a little while, but there is no way in a million years I would ever pay money for it.

To be honest, I am kind off annoyed by this recent trend of people trying to sell for money what in the past would almost always have simply been released as a free mod. Like, we have all of these young devs probably aged between 15-25 making something and then just dumping it unto digital market places such as steam. It's not helpful to the indie games industry at all. Now, does this mean there is anything wrong with making content like this? Hell no, in fact I love making stuff like this myself. But the difference is that I don't try to sell it, I just release it for the community to enjoy.

Re: Is it ok to create commercial game with ZDoom?

Sun Aug 05, 2018 12:08 pm

hardcore_gamer wrote:To be honest, I am kind off annoyed by this recent trend of people trying to sell for money what in the past would almost always have simply been released as a free mod. Like, we have all of these young devs probably aged between 15-25 making something and then just dumping it unto digital market places such as steam. It's not helpful to the indie games industry at all. Now, does this mean there is anything wrong with making content like this? Hell no, in fact I love making stuff like this myself. But the difference is that I don't try to sell it, I just release it for the community to enjoy.

I am going to have to disagree with you, and it almost sounds like you're more upset with people being successful at something and making a living off of it, regardless of their skill level, and you being trepid at attempting it yourself.

Ion Maiden is a community project that, by your standards, probably should be released as a mod. However, I personally see nothing wrong with someone making their hobby into a job. A life doing what you hate (i.e. "work") is a life that's not well lived - period. You may try to espouse that working at some desk job from 9 to 5 is the only way to go, but that kind of thinking is short sighted, ancient, and honestly really fucking dumb. I am sorry, but it is, and there's a reason why that kind of job setting is getting less and less common these days.

This is how people on Youtube get popular and become successful. They fill a niche that major corporations with huge marketing budgets refuse to touch. And it's the only way to increase the quality of the utter steaming shite coming out of the poop hole of the gaming "industry" (which, to be honest, about 90% of indie projects, with the notable exception of asset flips, regardless of quality, somehow manage to beat that, when visual effects are not considered).

You are no arbitrator to decide what people buy or do for a living. And people want to buy stuff that's not made by EA, Activision, Ubisoft, or any of the other shite-holes that have permeated the market with their "live services" and other pay-to-play crap that requires you to spend more than the base price of a game to have a proper gaming experience.

So this trend is here to stay. I am sorry, but some people don't like PUBG. Some people don't like Call of Doody 498494869877 or whatever fucking number they're at in the series. Some people don't like FIFA 2018 or whatever is going to continue having loot boxes shoved into it despite EA having "learned its lesson from Star Wars". If YOU don't like it - there's one thing you can do - DON'T BUY IT! But I will not brook you trying to tell people not to spend their money on what is honest to god better material than pretty much any triple-A dev comes up with.

Re: Is it ok to create commercial game with ZDoom?

Mon Aug 06, 2018 5:03 am

I quote and agree everything Rachael said.
Plus I wish see more things coming from the Ion Maiden team in the future. The preview campaign from ion is pretty fun.

Re: Is it ok to create commercial game with ZDoom?

Wed Aug 22, 2018 1:25 pm

hardcore_gamer wrote:No, my point was that once you start charging money for something you can't hold it to the same standard as you would if it were released as a free mod.
This I can agree with. Standards of quality are important, but that's primarily mindset. Webcomics would be a great example: There's quite a few i wouldn't call "fine art" by any means, but they convey intent and effort. And then there's audience mindset. If this ugly, unfunny garbage can be successful, I can certainly come up with something good.

Besides, it's becoming easier than ever to make a prototype. Sure, 90% of "make your own game!!" toolkits are trash, and the market is oversaturated with default resource cashgrabs. (This is where we all bash on unity, go ahead, get it out of your system, no need to post it though because we've heard it all before.) But why actively discourage people from literally following in the footsteps of the guys that pioneered the industry? The original Id guys were working in their spare time to - get this - make something salable.

Frankly, the "this should just be a mod" argument is almost always just a thin coat of paint over the good old sense of entitlement. It's a short step from "I wouldn't buy this as a game but I would play it as a mod" to "I wouldn't pay for this game but i would torrent it". One of the most pirated games in the USA is Garry's Mod. It goes on sale for around $5 with amusing frequency - Ever spend $5 on snacks? How long did that enjoyment last? (Besides, the game is 90% code and the rest is primarily Half-Life 2 models. Asset reuse?! Grab the pitchforks, everyone!)

I'm not saying everyone should rush off and monetize the first thing they come up with. The first things I've made are crap, and I understand that's very common. But let's not fault people for dreaming, and trying to build that dream. If I want to put in my time and my effort to make something I would be fully willing to pay for, you really have no right to tell me "this should be free!"
Last edited by NeuralStunner on Wed Aug 22, 2018 1:30 pm, edited 1 time in total.

Re: Is it ok to create commercial game with ZDoom?

Wed Aug 22, 2018 1:29 pm

I think, it is much better to do something like "if you like this game, you can send donation to author suing %list of payment systems% " than actual selling.
Because sometimes using this way author of a game/music,/pictures/etc, receive more money than from selling game/music/pictures/etc, for fix price.

Re: Is it ok to create commercial game with ZDoom?

Wed Aug 22, 2018 1:34 pm

Hardly. If artists could subsist on donations, there wouldn't be an indie market. And it's not as if the number of people who think "this is not worth money" is going to change just because it's entirely legal to keep their wallet closed.

I don't have numbers handy, but I believe the amount of creators that can actually live off what they receive through Patreon (etc.) is very, very tiny.
Last edited by NeuralStunner on Wed Aug 22, 2018 1:36 pm, edited 1 time in total.

Re: Is it ok to create commercial game with ZDoom?

Wed Aug 22, 2018 1:35 pm

NeuralStunner wrote:this ugly, unfunny garbage

Emmm.....you know that this is a banter over nowadays game industry, right?!

Re: Is it ok to create commercial game with ZDoom?

Wed Aug 22, 2018 1:46 pm

NeuralStunner wrote:Hardly. If artists could subsist on donations, there wouldn't be an indie market. And it's not as if the number of people who think "this is not worth money" is going to change just because it's entirely legal to keep their wallet closed.

I don't have numbers handy, but I believe the amount of creators that can actually live off what they receive through Patreon (etc.) is very, very tiny.

It depends on advertising and/or popularity of creator/game.

Even obvious slag can be sold for 999.99 + taxes + shipping + on beer to the courier, if it have good advertising campaign.