When we were building the levels of Outnumbered, I remember how much time we spent re-doing the placement of fences, lamppost and sidewalks because we moved one thing. Being able spawn any object along an editable spline that conforms to a surface seemed like a very handy tool to have for a future project. So I decided to do one in Houdini.
I went with a fence because it made sense, but I designed the tool to allow loading any mesh for flexibility. The mesh orientation is also flexible, the end user can switch between following the curve and using its local rotation. Right now, the tool accept two kinds of input: curve node and draw curve. It is also possible to change the terrain and the fence (or line of objects) will conform to the new one.
I wrote two blog post a couple months ago about the creation process where you can see how it evolved.