On each map there is a border that you can't build on at the edges, I'm not sure about the exact function of this but it has something to do with raiders and travelers I think, but the border is sometimes confusing for player, especially new players.
Would it be possible to hide everything outside the border? (or have a gray taint over it)
The border can still be used by whatever is using it, but its like behind the scene.
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I'm not sure how the map size is counted, with or without the border?
Lets for example say that we have a 100x100 map, and the border is 5 tiles on each side, and the border is included in the map size, then the actual buildable map is:
100-(2*5) tiles = 100-10 tiles = 90 tiles
If you then hide the border you could simply make the map 5 tiles larger in each direction.
Why would the border be confusing to new players? Most games with maps have finite maps.
Most players expect that you can use the full map that is given to you. You can't build anything near the edge of the map, so it makes sense to hide that part.
There's actually a reason for that, the edge was developed because some people had been exploiting the edges and corners as a place the raiders couldn't come from, so they would sit in the corner and only require half the defenses to protect themselves.
Ah, that makes sense now.
The edges aren't obsolete, you can do quite literally everything you might want to in the edges bar build, so stopping them from being displayed would just mean people could build right on the edge, and get attacked by things they couldn't even see. Though I do agree some indication should be given in the tutorial when you go to build what the border shows, just to avoid any confusion at all as to what the white line is.