So I've been away from RFC-DoC for a year, but got the itch to play again, and have downloaded and am playing 1.15. It's nice to get back into DoC.
But I've run into the following behavior, and am not sure if it's a bug or a feature. (And if it's a feature, I don't know where I would have looked to find it explained, so apologies if this has already been explained and justified):
After your civilization builds a wonder, the culture it receives per turn drops at least 10% from what the game reports you are getting and what the game itself promises you will get for owning particular buildings and Wonders. Example:
You as Egypt build a city (with a palace) and earn 2 culture pts per turn. Later you build a temple and earn 3 culture pts per turn. So far all is going as the game documents it should. But then you build the Sphinx. This should add 4 culture pts per turn. (If that's the right number; I might be remembering wrong.) The game, both on the Culture slider of the main screen (once that slider has been added with tech) and in the city report screens will tell you that you are earning 7 culture pts per turn. But the next turn it will not give you 7 pts; it will give you 6.3 pts. If you then build the Pyramids (6 pts per turn, IIRC) you will not earn 13 points per turn, but 11.7. And so on for the rest of the game: The game will assure you that you are earning X culture points per turn, but actually you are only getting 0.9X.
That is for Egypt. For Babylon it is even worse -- play as them, and after you build a Wonder your culture per turn will only be 80% of what you are supposed to earn, and what you are being told you are earning. I haven't checked other civilizations to see what their numbers are.
Now, if there is some feature in DoC that nerfs culture per turn when Wonders are built, I guess that's okay. But it's an unpleasant surprise to notice that you're only getting 80% to 90% of what you are being told by the game itself that you are earning. It is no longer enough to glance at the Culture slider to see that you're earning (say) 64 pts per turn. You have to check your city stats on back-to-back turns to find out what you're really earning.
So is this a bug in Culture calculations? A bug in the screen reporting? Or an intended feature?