Main game, and I meant culture points.
Okay, got it.
It sounds like I'm looking at the wrong number in the tooltip.
Oh! In the tooltip. All those numbers in there get added around, so it's very complicated to calculate what it will actually be. There is the base amount they add, then all sorts of effects based on other adjacent tiles. So if you're trying to go off the tooltip, you'll have a devil of a time doing all that math. You can, but it would take 30-40 seconds per tooltip for me, personally.
What do the numbers represent on the map itself? If it says +100 on a specific square, does that mean +100 is what I'd get for placement there, or do I have to sum up that square with all the ones surrounding it as well? That's part of what confuses me.
The numbers on the map are the game saving you the time of doing all that math -- that tells you exactly how much culture you will get from placing your tile on that square. The only thing that matters in terms of culture generated is that number on the tile you place it on. So if it says +100, you'll have 100 more culture from placing the building there. If it says -1, that's what you'll get.
The numbers in the tooltips tell you the story behind why the numbers are what they are on the map, but the map tells you the final result. And when it comes to something like -1, that's a secondary rule that is basically saying you get that score for placing a tile on an existing tile of the same type.
Hope that helps!