GZDoom & Making games with it.

[forgettable pyromaniac]

So, I know GZDoom has been used in a few chunk of games released on steam and has been used for many other wads that do use some regular .wad assets, but I wanted to ask, right from the people who know 10x more about this stuff than me: What's the legality? As in, what am i allowed to do with GZ if I want to make my own game with it? Can I make a game with it and upload it to itch.io just fine? Steam (if I had the money)?

 

I know if I wanted to, I cant use any doom assets, which is a given. But assuming I made everything that would in the .wad myself, what about the engine? Can I edit the exe name and icon? Do people make their own forks and build it that way, or do people only use the regular editors you'd expect (Slade3 and UDB)?

 

And also, as someone who hasn't used GZ since they first started dooming, how customizable is it w/o building from source (i.e., can you make your own settings menu, can you force certain things like antialiasing/resolution scaling or something to keep the game looking kinda crunchy?)

 

Trying to get all the information I need before I even consider doing something like that.

[Edward850]

 

Edited June 8 by Edward850

[forgettable pyromaniac]

1 hour ago, Edward850 said:

...

That definetly clears up the engine side of things (just GPL it, afai can tell), but not nessecarily the way to go about it (the questions about GZ in general).

[LuciferSam86]

The rule should be:

- If you modify GZDoom you need to release the changes under the same license (same as what SELACO is going to do after EA)

- You cannot use the original assets (you need to have a .ipk3 file, forget WAD format is too limiting)

 

then you can do whatever you want, I guess. Your final message is too unclear IMHO

[kalensar]

DisDain and Selaco Beta both use modified GZDoom engines as part of their app and both are on STEAM. The basic gist about using GZDoom as a commercial engine is that everything must be readable on inspection by anyone of the files used and cannot be treated like corporate secret even though product can be modified only to work with your game. I think that is about the concise way I can translate the licensing used on GZDoom itself.

 

Basically yes you can and there are plenty of examples already on STEAM using this same premise. The hard part IMO is making the original assets. 

 

One example that I have personally done was make an IPK3 based on the GoldenEye TC i compiled some time ago. There's no difference from it and the actual mod released except I made an IPK3 for myself. Due to my interpretation of permissions, I basically wont ever release the actual GoldenEyeTC IPk3 itself, but there is no need either since it performs identical to the mod. 

 

Spoiler

 

Edited June 8 by kalensar

[forgettable pyromaniac]

1 hour ago, LuciferSam86 said:

...

- You cannot use the original assets (you need to have a .ipk3 file, forget WAD format is too limiting)

 

then you can do whatever you want, I guess. Your final message is too unclear IMHO

I don't know the difference between pk3 and wad, afaik it was just a different way to format the same stuff (with directories instead(?))

 

Basically, was just asking about the basic like "this is the most important bits if youre planning on getting started with GZ" because I've made exactly one thing for GZ and I barely understood what I was doing, I'm much more familliar with vanilla/limit-removing creation.

 

1 hour ago, kalensar said:

DisDain and Selaco Beta both use modified GZDoom engines as part of their app and both are on STEAM. The basic gist about using GZDoom as a commercial engine is that everything must be readable on inspection by anyone of the files used and cannot be treated like corporate secret even though product can be modified only to work with your game. I think that is about the concise way I can translate the licensing used on GZDoom itself.

 

Basically yes you can and there are plenty of examples already on STEAM using this same premise. The hard part IMO is making the original assets. 

Proper english for the liscensing rights is always nice :) thank you.

 

And as for assets, yeah - I knew that it would be a lot of effort and time, thats why I wanted to double check with people who knew better.

[kalensar]

13 minutes ago, forgettable pyromaniac said:

thats why I wanted to double check with people who knew better.

 

Yup! If you're want to learn how to work with GZDoom as a modder or game creator then ZdoomWiki is going to be your best starting point for learning how the actual coding works. There are a couple of other resources such as ZDoom Forum's discord server and a github designed around helping with ZScript as well. Theres a lot of tutorials on Youtube for Doom Mapping and coding as well.

 

For start: a Pk3 is a ZDoom mod file that uses ZIP. a PK3 is technically a ZIP file, but PK3 refers more on how the files are organized rather than the type of compression it uses. Pk7 is the same way but its a 7Zip file compression instead. On ZDoom Wiki the article "Using Zip Files as WADs" gives the structure in detail and how it pertains to a doom WAD file type. So basically you can use that same article to build a WAD format or a Pk3. Generally speaking, the only Source ports that use PK3 format are the ZDoom family, and most other source ports require WAD format to run mods or maps. Of particular note ZDoom family still requires Maps to be built in WAD format as there is no PK3 variation for that.

 

The base tool box of Doom modding uses the following programs

• GZDoom or any other source port
• SLADE3
• UDB--Ultimate Doom Builder
• And you can even use 3D models once you learn how to implement them in the engine so Blender or some other 3D model program
• Then for custom art you want what ever program you are comfortable with such as GIMP or Photoshop or Paint.

Edited June 8 by kalensar

[Redneckerz]

3 hours ago, forgettable pyromaniac said:

That definetly clears up the engine side of things (just GPL it, afai can tell), but not nessecarily the way to go about it (the questions about GZ in general).

The absolute easiest way is Nash's Standalone Game Template which gives you the bare functionality to be standalone so you can just use it as is.

 

The thing is, you ask a lot of things all at once, so Edward's post is in general one to follow.

• What's the legality? -> Distributing standalone games is perfectly valid as long as you comply with the GPL (Which generally means releasing the source code to your engine)
• What am i allowed to do with GZ if i want to make my own game with it? -> Practically everything. Start with Nash's Standalone Template and replace any and all assets and you are good to go in releasing it, along with whatever the GPL license stipulates
• Can i make a game with it and upload it to itch.io just fine? Steam (if i had the money) -> I feel like i am constantly answering the same thing, but yes you can make a game and upload that to itch.io, along with whatever the GPL license stipulates
• what about the engine? -> You can both modify and not modify the engine, or you can fork it and make modifications. Either way, all modifications MUST be open sourced per what the GPL license stipulates
• Can i edit the exe name and icon? -> You may change the executables name and replace the asset for the icon.
• Do people make their own forks and build it that way, or do people only use the regular editors you'd expect (Slade3 and UDB)? -> Selaco uses its own custom fork (Pancake) whose source code (including its newfangled UI) must be open sourced per GPL. For level design, they use the same tools as everyone else. Some may modify UDB to suit their custom needs since its also a open source program
• how customizable is it w/o building from source (i.e., can you make your own settings menu, can you force certain things like antialiasing/resolution scaling or something to keep the game looking kinda crunchy?) -> In case of GZ, you can go far with ZScript, in addition to DECORATE, ACS. ZScript is the preferred method to modern day GZDooming. So yes, you can do all that without source. However if you want to include new engine effects that GZDoom does not natively support, editing the source is required

 

So what questions about GZ in general aren't answered?

Edited June 8 by Redneckerz
Clarification

[TwelvNighn]

wasnt the creator of brutal doom making a game in gzdoom?

i think it was called brutal fate or something

[Gez]

To complement what was already said, a few useful links:

Nash's Standalone Game Template

DEFBINDS

DEFCVARS
IWADINFO

License

 

[forgettable pyromaniac]

55 minutes ago, Redneckerz said:

... So what questions about GZ in general aren't answered?

Yeah no that's about it, everything important there :D thank you

 

33 minutes ago, Gez said:

To complement what was already said, a few useful links:

...

that is also extremely helpful, thanks gez !