One wooden floor tile is 1 meter. Trolls have a 30 meter perception radius and a 20 meter alert radius at a 90 degree angle in front of them. If you leave alert radius through distance or angle the troll will attack something else. Their priority after you is live stock (if they can see them), crops, behives, other buildings.

The if they can see them part is important. If the boars are in a closed barn instead of an open pen the trolls won't be able to see them and will attack the next lowest priority target.

https://steamcommunity.com/sharedfiles/filedetails/?id=2853688746
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