I made invisible level blocks out of primitives (ellipse, cylinder, block) that were close to the shape of the mesh. I then used the "c_content" function to check whether or not a point was within empty space or a passable or unpassable block. In this way I could distinguish whether or not the specified point was inside one mesh or another, or neither. In documentation however, it says that this function is abandoned an not to be used in new projects. Also if your mesh entity moves you would have to move the level blocks along with your mesh.

@MasterQ32 - sounds like a better idea!