Hi Andy & rlclegg,
I’ve used the same/similar technique on a line which rises from 5 metres above sea level up to a range of high mountains.
See below for a sample method.
I laid one long straight length across 19 baseboards. As in 1 below (which has been shortened for clarity - and lack of draw distance!). There are only two spline points. The first at ground level, the last at the rail end in the mountain.
I then placed several spline points (2) in the lateral position of where the curves needed to be pulled. The heights are automatically set – no adjustment required.
Then (3) simply pull them into the position required and use “Smooth spline height” tool to fill in the terrain.
The mountains were then added around the terrain where required, with smooth spline height re-used as necessary. Any dramatic shift of gradient, (if a spline point were to be moved far enough laterally to make a difference), could be corrected my moving a spline up/down as required I guess. I didn't find I needed to though, other than at a couple of stations where I had to have a horizontal track to match the platforms. (Having said that, it wasn't on a prototypical part of my route, where I've been far more fussy and precise).
However, I found it a useful technique for basic route building, and beats doing it a section of track at a time.
Imageshack
Cheers
Casper
