Bug: Extreemly large city growth for unknown reason

[DrSuperGood]

As discussed on the server, the city Stashridge @4603,3340 seems to have an excessively large growth rate for being an island in the middle of nowhere. It grows several times faster than much better connected and less remote cities. Only thing stopping it from growing is that its run out of land on its tiny island.

[Jando]

I'm seeing that as well on my games.

Screenshot here: http://files.simutrans.com/index.php/s/bzYq0SsKkH3u0q7
Saved game here: http://files.simutrans.com/index.php/s/TOnXmiOqQapGwxR

Town (without any transport service) grew from 7.098 to 30.496 in 10 months.

[zook2]

Just a wild guess, but could it have something to do with a relatively large number of tourist attractions? I count a cathedral, two sports fields and two towers, and they might generate a lot of walking traffic, which is (perhaps) linked to town  growth.

[Rollmaterial]

That seems to be a general problem with islands. I have systematically disabled growth for island cities in my two last solo games.

[zook2]

Now that you mention it, I've seen something like this in one of my games, but with version 11.3x from ages ago.

[killwater]

It is not something uncommon. I have seen it quite a few times especially on islands. They sometimes spread to the mainland through many tiles of deep water though...

[Jando]

Yes, it's an old "bug", not something that's new to the latest release. It's also not limited to islands.

[Phystam]

And also, through high mountain, isn't it?
In "stadt_t::enlarge_city_borders()" function, the city will be enlarged regardless of the ground height, but only considered the next city.
Probably we also should consider sea and the climate difference between the city hall and the tile to be expanded, I think.

[DrSuperGood]

Growth rate seems to have slowed for the city once I expanded the island. Maybe it was meant to be a bigger city but ran out of land during generation so it had a lot of hidden growth.

[jamespetts]

Growth rate seems to have slowed for the city once I expanded the island. Maybe it was meant to be a bigger city but ran out of land during generation so it had a lot of hidden growth.

It is also possible that the incorporation of the multi-tile city building code (which also contains a fix relating to population) might have had an effect on this.

[DrSuperGood]

In any case this report is solved as there is no evidence of anything wrong with that city anymore.

[jamespetts]

Splendid, thank you for confirming.