"Lines" on the minimap?

[Shask]

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Look on the radar, you can see vertical/horizontal lines where the image of the trees has been cut off. Was this the edge of the world in a time gone by? Can someone explain?

I'm emigrating to a new supergrid in the far west for no reason, just want to hermit there.

[spectacle]

It's nothing special, the minimaps are generated separately, and each tree only appears on the map of the grid it's actually located in, even though the image of it should overlap into an adjacent map. That's why it looks like the trees are cut off. So what you're looking at is the border between local grids.