Knife Project in Blender to cut a 3D mesh from 2D contours
In this video, learn how to use Blender's Knife Project tool. This lets you segment a mesh by projecting the contours of another object from the current view. This is a particularly useful example where GIS data has been imported using BlenderGIS. The terrain is in 3D, but the contours of lakes and rivers were only available in 2D, which is often the case with GIS data.