I'm making RTS project on Unity3D.
I created terrain with Unity's standard Terrain tool, and added textures of grass, mood etc. on it. Then, for creating "man-made" objects of terrain (roads, sidewalks, road curbs etc) - I'm created this objects in separate assets, and placed on terrain.
And I have one issue with this solution. On moving camera away from the terrain, terrain's texture(e.g. mood) are flickering under roads, sidewalks and other objects. AFAIK, this bug caused by insuficcient accuracy of floating-point coordinates in Unity3D engine (?).
Now, as I concerned, my approach to creating terrain objects is not correct. I must create one mesh with terrain, and all manmade objects in 3D modeling software, and then create UV-map for texturing all of it. Is this approach correct? If "yes", is any special approach for modelling and texturing so large and complex object as terrain?