If you have your road surface set up in a good way then you should be able to just us the surface mapping that exists by default on surfaces. Attached an example where I created the road surface by using Sweep1 on a curve. A line perpendicular to the curve was used as the shape.
Check the image mapping where I repeat the texture as many times as necessary to make it look good.
road_texture_example.3dm (4.1 MB)