Sorry for my bad english. I am learning blender. I have modeled a toy car and I have made a hilly floor. I created a path and trid to pull the path in the shape of the bumpy hill. The car follows the path ok, but looks not nice. how to constrain path to the surface of the bumpy floor so that it sticks to ground. Thank you. Please help me, I am stuck.
thank you
This is a perfect candidate for the Shrinkwrap Modifier that is in development.
For now, I don’t know of any real solution, but perhaps soft bodies would work?
Hopefully someone else can give you some better advice.
Hum… My guess would be: select a Edge Loop from the length of your path ( Edit Mode, RMB Edge Select Mode, select) and duplicate it… Now here comes my ignorance (but i’m sure someone will tell the truth!) This done THERE MUST BE A WAY to have it as a PATH in the outliner (would be a scandal if not).
That could be a very elegant manner to have an exactly shaped path, isn’t it?
Sorry that nobody could give you the “ultimate” hint! But be patient… it will come! 
Hi almux thank you. I tried your steps, but it works not for me. The problem is that I then have to re do the hill , but every time the loops don’t come my way.
egan where to get Shrinkwrap, I couldnot find it.
Re-do the hill? How come?!? The new path ligne should only be a copy of one loop, how can it influence the structure of the hill?
The only step i ignore is HOW to have this created copy of the hills edges to become a independent element usable as PATH… ;p
hello Almux, thank you sir. …edges to become a independent element, that was esy sir, just used script edges to curve and then curve path and done.
but i used subdiv and then sub surf on select face and my loops dont go as i want.
i can manual select edges, but too many, too tedious but now no option
I thought may be redoing the hill could give more control.
don’t know if works or not.
will try.
where to get shrinkwrap?
You could use “retopo” to build the path with edges and then use the script to convert it to a curve.
Add a follow path constraint to the cube.
This way you’ll have a basic movement, then you can tweak the tilt with T.
Thankyou elclanrs
never trid retopo, but will give try today
will let know if worked.
Currently, shrinkwrap is being developed, so it is not available in 2.46. If you want to try a development build, here you go: http://www.graphicall.org/builds/builds/showbuild.php?action=show&id=669
But for now, I guess retopo might be the best solution.