Context: I saw a post a while about Paradox Interactive cancelling their life simulation game Life By You and someone commented saying they wish Paradox Interactive would release what they’ve completed under an open source license. Follow up comments said it wasn’t feasible largely due to a Russian nesting doll of licenses that wouldn’t be compatible.
Question: What would be some obstacles in making a modern stereotypical AAA or indie game open source? Or even just segments for it for that matter?
This would be ignoring the financial impact. It would be like CD PROJEKT RED making Cyberpunk 2077 as open source as possible as a an action of good will.
A AAA game’s source code can be like 100 Tb and with every update they’ll have to reupload it. Also there’s always stuff (usually music) the developers don’t own and buy a cheap restricted license for.
Where did you take that number from? The source code is by far the smallest part of most games.
Well, one available case you can look at is Uru: Live / Myst Online, currently running under the name Myst Online: Uru Live: Again.
They open-sourced their Dirt/Headspin/Plasma engine, which required stripping out - among other things - the PhysX code from it.
A few potential obstacles:
- Use of proprietary third party libraries. Havok seems to cost money for example. I’m not sure how Havok would work out in an open source model, but there are probably many other third party libraries that would stand in the way as well.
- Distribution of assets. The game is not much without its assets, and many of the assets can be third party. For example Quixel Megascans. Even old games like Super Mario 64 heavily used third party textures and sounds. Not sure how they would like their assets be distributed freely.
- Music. If the game uses licensed music this is a no go. It’s even difficult for companies themselves to release their old games with their original music.
Another NDA’d thing would be console integration, theoretically you could better optimize something for the hardware unlicensed if you had reference code
I’ll add something which is not mentioned: Unreal Engine, one of the most popular game engines, is source available, but not open source. Many games modify it but its then impossible to release those sources. I’m guessing that it’s the same with many other engines…