WIP Guide: https://docs.google.com/document/d/1viZSm7OquK8vhahskP0Bthy9uQufmz2PA01g1SHzFd0/edit
Terrain Guide 2: https://docs.google.com/document/d/116vVaxW02aydAI-VDHLhW4USuLEiJDNS2YoiFCmkv-M/edit#heading=h.dfdqwrhwsmv6
Heightmap Sources: https://tangrams.github.io/heightmapper/
BI Documentation: https://community.bistudio.com/wiki/Arma_Reforger:World_Editor:_Terrain_Preparation_Tutorial
Blender to ASC Height Map Tool: https://community.bistudio.com/wiki/Enfusion_Blender_Tools:_Import/Export_ASC_Elevation
Forest Generator System, also works for other.
Select Vector Tool
Click on New Polyline
First left click into the scene, then Ctrl+LMB adds point in front, Alt+LMB click at back
Once you are done, go to object properties and check Is Closed box (at the bottom)
Look for FG_ in Prefab Library or Resource Browser
Find what forest you are looking for and drag'n'drop it right into Hierarchy in WE straight onto the vector
You have a forest
You can edit vectors only while in Vector Tool.