I once did some minor patches on the OpenTTD code base, but didn't go far, as I didn't like the code style. (This is no objective critizism, I have an idea where they came from, but just not the style I at that time wanted to deal with for a fun/side project)
I assume the maintainers take pride in it, creating a game which is liked by many is rewarding. Especially if you like the game yourself.
Depending on your day job it can be quite relaxing to deal with other problems.
But if you don't like the genre and don't like the codebase and don't like the people in the community and don't like ... it's probably no fun :) in the end only you can judge for yourself.
One thing is certain: It won't earn you lots of money and it's unlikely to be the reference for a new job. (And therefore takes a work aspect out of it, which to me is good)
I had plenty of fun to make an AI for it. My first software project that was used by others. As bonus, it actually worked quite well (called AIAI - Automatic Idiot AI).
Though as a programmer newbie I got confused by race conditions introduced by fact that game may be saved at any time, potentially leaving things in the middle of construction.
I still have plans to get back to it at some point.
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AIs and many other mods were created independently, support for modding was beautiful.
I feel software release announcements function as a way to "advertise" some relevant software on HN. Why should that be forbidden but Show HN be allowed?
Just to help people who never knew of it to discover it. The same like when people post links to Wikipedia articles about some curiosities every some months. OpenTTD is a masterpiece free game and can make some people happy.
Hmm, this sounds almost "edgy"? But then again OpenTTD is a lovely game and well worth the look for anyone who's one of today's lucky 10'000: https://xkcd.com/1053/
It has low hardware requirements, runs on many platforms, has multiplayer that "just works" and a rich scene of user created content, like alternate graphics/sound/music packs and plenty of maps, some of which are inspired by real world locations! It, alongside Jagged Alliance 2, is one of my go-to games if I ever want to play something on really low end hardware (think netbook), or just look at some nice pixel graphics.
And also there's a city builder game with industries and transportation called Workers & Resources: Soviet Republic, where you build the city instead of letting it grow organically like in other games (placing infrastructure in the middle of an existing city was annoying in OpenTTD): https://store.steampowered.com/app/784150/Workers__Resources...
Hopefully that adds to the discussion a little bit, thankfully it doesn't seem like this genre is lacking in games! But when you don't want to invest any money into it, OpenTTD is well worth a play, or to just serve as a nice entry point into the genre. There's also a Wiki with tutorials and such: https://wiki.openttd.org/en/Manual/Tutorial/
I found Transport Fever 2 very disappointing. It dumbed down the economic model: businesses turn out cargoes even if you don’t carry them to market. It reduced supply chain challenges: the first game has interesting twists, like businesses whose output was halved if you didn’t carry less-desirable byproducts away. The second game simply eliminated this.
It also didn’t make any huge improvements otherwise and was really more like a 1.5. I recommend the first game over the second.
OpenTDD will always be my go to example for a product of love and good out of open source. People who love the game kept it alive and improved out of pure enjoyment.