5 replies to this topic

[Roebloz]

Hey, Roebloz here, you might remember me from such hits as Roebloz's World Adventure 1-3 and...Oh right, that's all I posted here. So, I was curious, and as you've read the title; Would it be legal to make an indie game using ZQuest Classic as the engine and then sell it, provided all the copyrighted Nintendo assets are removed/replaced? I know it's open source but I'm not quite sure if that would be allowed or not (Better be safe than sorry).

 

And no, I'm not asking this in a pretentious way like "My quest idea is so good it's worth money!", more just a "Hey, I'm decent at making ZC quests, could be cool to be able to make a custom game of own with its own IP and get some money from it, putting those skills to good use." Sorry if this topic is controversial or anything, I'm just very curious and interested.

 

(By the way; How long as ZC been renamed to ZQuest Classic? I was completely unaware given the lack of any updates on zeldaclassic.com, I thought the game was just dead. I'm still going to call it Zelda Classic in my head, though~)

[Joelmacool]

I'm not too sure as to the legality of selling anything made on the ZQuest Classic engine, but I can say that the reason zeldaclassic.com has lacked any updates in recent history is because all active development for the engine moved over to a website called zquestclassic.com!

In terms of legality, it might be worth asking the developers over on their discord, if you don't get any substantial answers here at least.

[Mani Kanina]

Hey, Roebloz here, you might remember me from such hits as Roebloz's World Adventure 1-3 and...Oh right, that's all I posted here. So, I was curious, and as you've read the title; Would it be legal to make an indie game using ZQuest Classic as the engine and then sell it, provided all the copyrighted Nintendo assets are removed/replaced? I know it's open source but I'm not quite sure if that would be allowed or not (Better be safe than sorry).

It's a complicated question with a complicated answer.

Assuming you have the rights to all assets in the quest you make then there are currently a list of things you have to do:
A. Any custom code/script in your project you've made you need to release under the same license as the default headers (and zelda classic itself) is licensed under.
B. Any script you import from anyone else have to also be compatible with this software license. Most scripts and headers you find hosted here on Pure are offered without a listed license, ergo you would not have the legal right to redistribute them under such a license and you'd need to either convince the maker of them to release it under such a license, or simply not use it.

Furthermore, the engine itself was made open-source under a specific license, but there's some complicated questions in regards to that so you should ask the official devs to be sure. But assuming you get the green-light from the devs that it wouldn't be a problem, you can probably go ahead.

[connor.clark]

In short: yes it is legal, but you must follow some legal requirements.

 

Unfortunately the license (GPL 3) isn't the most ideal for a game engine, and is based on mostly immutable decisions from decades ago.

 

By distributing ZC's binaries yourself, you must follow the software license of ZC and the licenses of its various dependencies[1]. That can be accomplished by:

 

1. Including the license text of ZC and all its software dependencies [2]

2. Providing the source code used to create your game upon request (zscript, etc.) [3]

 

Note that while giving people your code is technically merely "upon request", it is typically fulfilled by publishing the code somewhere online, or simply distributing the code along with the game. You could just send the code to anyone who emails you, but if you don't show good faith (by not responding in a timely manner), you would be in violation of GPL. Since anyone who gets the code in this way is free to do anything with it (given they also follow GPL), they could also decide to publish it somewhere; so you might as well do that yourself.

 

It's also a requirement to provide the source code for ZC "upon request" - but that can be fulfilled by just linking to our GitHub. If you fork it for any reason, of course you'd have to make that code available somewhere in order to legally distribute its binaries.

 

Things excluded from GPL (and software licensing in general) are stuff like artwork, story, gameplay mechanics, etc. Software licenses are just about code, and only kick in when you distribute binaries. In other words, your game's implict (or explicit) trademarks or non-software copyrightable material are NOT relevant here.

 

Based on my understanding of things, the actual qst file also does not fall under GPL. For example, if you only distribute a qst file with directions to load it in ZC, you wouldn't have to follow any part of the GPL (as you would not be distributing any binaries). Of course, that's a bad idea for reasons unrelated to licensing.

 

Finally, I'm not a lawyer. Anyone planning to spend the time and resources needed to make a game should first validate all this with a lawyer. If anyone ever seeks counsel on this topic, it would be helpful to share what you learn with this community.

 

EDIT: one more thing, many assets currently distributed with ZC (like sfx, tileset graphics, etc) are not necessarily under a permissible license. It's highly recommended to not utilize any of these in a commercial game, for the time being.

 

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[1] A decent summary / discussion about game engines licensed under GPL: https://gamedev.stac...o-build-a-proje

 

[2] ZC comes with a `licenses` folder, which has ZC's license and all its software dependencies' licenses. I just noticed that the package export feature of ZC is not including these in the output folder. I'll fix that soon.

 

[3] There is some ambiguity here about whether this includes just scripts that use the ZC standard library (std), or any script given that ZScript interfaces with ZC at runtime. The safest interpretation is that all scripts fall under the GPL when distributed alongside the ZC binaries. Additionally, scripts found on this website are licensed separately by their own authors, and you should seek permission before using them in a commercial game.

 

[Roebloz]

I see, thank you for the replies. I'm not planning on using any advanced scripting (Since I don't really know how) but I'll ask the devs before anything. At worst I can always just use ZC as a means to plan out the game and then recreate features in a free engine (Though that would be a lot of extra work and would sort of defeat the purpose )

 

I don't have the means to a lawyer, so I can't help bring answers there unfortunately. I if I do end up making this with ZQuest what I'd ideally want is to distribute it with a more stripped-down executable that only includes ZLauncher and ZPlayer (Since everything else wouldn't be exactly needed) with only the QST file itself being closed-source/copyrighted. (Obviously it'd be rather easy to pirate and share around, but considering the amount of games I haven't paid for myself, I'd be quite hypocritical for complaining, I know not everyone has the means to buy a game)

Edited by Roebloz, 19 May 2025 - 11:43 PM.

[klop422]

To be honest, given ZC and ZQuest is trying to separate itself (in principle) from Zelda (at least in legal terms) and things like this might become more common (even if most serious game developers do use other engines), it might be worth writing up a legal guide for this and sticking it somewhere it'll be seen (plus adding it to docs and wiki and so on). Given the ambiguities regarding scripts, might even be worth adding some legal license-y stuff in there (and the rest of the database)?

 

But maybe that's thinking too hard about that stuff haha. All I can personally say is that anything I upload to the database is definitely free to use for anything in relation to ZC, ZQuest etc.