   Adding a road to terrain
  How would you go about adding a road to a terrain generated with a heightmap? i tried just creating some triangles and adding a road texture to it, but because my road coordinates are singles(or floats in c#) it can be places anywhere so the terrain pokes through it in some places... I also tried drawing to a texture and adding roads to that texture, then drawing the terrain texture from that texture, but it ends up gettin shinked and mirrored :S and help would be great!   