Hi there,
Depending on what you want – if you want something more like a dirt path, for example – a smooth area on your terrain but one that adheres really tightly to the underlying terrain – I would do the following:
- Create your layout generator but Make sure you have not connected your terrain into it.
- Create your road shapes appropriately.
- Take the output of the layout generator and use it as a mask input into a blur device. Wire your terrain into that blur device and set the radius to a moderate value. You now will have a smooth path on your terrain.
If you want a road that does carve through the terrain somewhat, but never gets too far off of it, here’s a good method around:
- Create a layout generator and hook your input terrain into its terrain input.
- Create your road shape with plenty of control points. You can add additional points after creating by rcliking on a vertex and choosing subdivide if need be. (of course also set your fallof distance, curve, etc appropriately for the size of your road)
- Select the terrain device from before that you want to match so that you can see it below your road shape
- Right click on your road shape and choose “Drop curve to surface”. This will set all the vertex heights appropriately so that the road is located as nearly as possible to the terrain.
Here’s an example picture of a road placed onto the default world using the second technique:
