Thanks for emailing. I hope you're enjoying using RailClone.
1) When creating roads, I do so by creating a middle spline. So then I have the road. How to add curbs from here? I obviously don't want manually select all edge splines and "convert to spline", as that would take forever on big scenes. My natural thought was to put on one RC instance for each curb side, but maybe I'm thinking wrong.
RailClone has an option to duplicate and Mirror a linear array onto both sides of a central spline. This is ideal for adding pavements, streetlights barriers and more. You can see this technique used in the Civil View Interop. tutorial
. Though it discusses Civil View it is all essentially based on using a central spline area.
2) Is there a nice way to get the road blended in the terrain? Like if I lower the road, then the terrain will bulgde downwards with the road?
I'm afraid at the moment RailClone is not able to affect the surface terrain, although it can follow existing surfaces. You can read more about this in the Documentation here
You might also find this post
useful, it also discusses the creation of junctions using modular pieces.
3) Is there a way to create closed outline spline roads with RC? Say if I want to have a part of the road that is 0,5 m wider?
You could use a clipping spline to define the road surface and also the same spline to drive the curbs. To read more about clipping check out this chapter
in our Next Steps with RailClone guide. I've also attached a sample file to this post.
This feature has been on the wishlist for a long time. Unfortunately it involves several technical challenges, futhermore RailClone is designed to be a generic tool, so we cannot assume certain shortcuts that would be used in a specialized road making tool. Genuinely we would like to dedicate some time to this problem, but at this point there are too many features in the to-do list, and not all of them can be implemented. We'll continue to look into it.
I hope that helps, please let me know if you have any further questions.