FOSS gamedev and creative worlds

Is there any street mod that has diagonal or curved street nodes? It seems like streets or Cheapie's Fork: Roads, could just add some code and textures. I think it would really be useful. You can't really make realistic road without diagonal textures or curves. Not every turn in real life is 90 degrees. I have thought about editing one of those mods myself. I could probably get the code to work, but I really stink at making textures...