TransDEM Forum

Hi. I have only recently started using TranzDEM and have had a reasonable amount of success with creating routes with the package. I am now trying my first attempt at a real world route (between Cardiff and Newport) and have successfully imported the route, map tiles, vectors and DEMs etc into trainz 12. Only problem is that the rail track , although correctly placed laterally, appears to follow a rather 'rollercoaster' path vertically (up and down very steeply in parts). I tried getting track elevation figures in explorer and they were indeed very eratic heights. I understand that TranzDEM gives elevation as actual figures from sea level but how can I get the track to follow a more natural (smoother and flatter) path without spoiling the general layout of the route?

The track spline points created by TransDEM simply adopt DEM elevation of that particular point. With a standard medium resolution DEM, you will indeed end up with rough track, roller-coaster style. A 50 m DEM cannot not resolve cuttings or embankments, scale is just too low. Trainz Surveyor tools will be needed here for forming a proper track bed and laying smooth track.

Things might look somewhat different, when high resolution DEM is available. Last year the UK Environment Agency made their LIDAR data public, but it appears Wales is not on the list. (TransDEM would be able to process the data, though.)

geophil wrote:The track spline points created by TransDEM simply adopt DEM elevation of that particular point. With a standard medium resolution DEM, you will indeed end up with rough track, roller-coaster style. A 50 m DEM cannot not resolve cuttings or embankments, scale is just too low. Trainz Surveyor tools will be needed here for forming a proper track bed and laying smooth track.

Things might look somewhat different, when high resolution DEM is available. Last year the UK Environment Agency made their LIDAR data public, but it appears Wales is not on the list. (TransDEM would be able to process the data, though.)

Thanks for the information and advice it is appreciated. I thought that might be the problem with the height given on the spline points. It looks like some extra work when I continue in surveyor, since I have to change the track into 4 track wide (and more in places) for most of the route anyway.
regards
Bill

Bill, have you seen this: http://forum.transdem.de/viewtopic.php?p=2221#p2221 ?
LIDAR high resolution DEMs now also available for Wales!