"Smooth Spline Height"


New member
Is there a way to adjust the height that the "Smooth Spline Height" tool raises/lowers the terrain under the tracks? I wish it would set the track a little lower in the terrain instead of so high; I would like it more flush with the track level. Any chance of that??
Thanks, Chris. What I am trying to do is adjust and smooth out the track and terrain on my newly generated TransDEM route. The track follows the terrain and I know I have a lot of work to do on straightening the track, but it would be easier to do by being able to adjust that value.

The best that's on offer at the moment is simply to lower the height of each of the track splines to the correct level (I can't remember the exact amount), tedious work but you get there in the end.

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It always smooths out an area 20m from the track, and floats the track, with a 0.02m gap above the terrain (to solve the track flicker problem in TRS2004) ... It is not adjustable, as it is coded into a ja file, and encrypted there.

I would be more than happy to share my techniques on grading tracks on a DEM with you, and by using Free Skype you could view my monitor, and learn my techniques, by seeing what I do.

Basically, I use MB Quad as a 4 track spacing guide, as it is a PRR 4m track spacing, and MB Quad is highly visible on the Trainz Minimap.

I use MB Quad for all the straight a ways, and on curves I use single track.

I lay all the MB Quad straights, all intersecting each other, then measure back both ways using the Trainz ruler, 300m from the intersections.

Then I insert spline points at that 300m mark ... and install single tracks, connecting the straight a ways.

As a MB Quad track can be dialed it to apply a 1.87% grade, it will raise the next single track height spline point ... but a single track typed in gradient will not raise a MB Quad track spline point.

There is a way to clone MB Quad track, and make it into a 4 track, single track, spline, by editing the config file, but I haven't perfected that use as of yet.

When I have all my straights, and curves connected, I manually lower all spline points to just a hair below the terrain, slightly sunken.

It take practice to iron out all the gradients so that they do not look like this:


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The photo's are a radically high powered telephoto shot that dramatically compresses a scene ... but real RR's are a series of up's and down's all along a straight a way, and are not perfectly flat and symmetrical.

I always look straight down, from directly overhead, when laying tracks and gradients.

I never press "Smooth Spline" until months down the road, when I have 100 miles of track, still with sunken spline points all over creation, in cuts ... As prematurely pressing the smooth spline tool button, and hitting "SAVE", is a great way to permanently deform your terrain, ruining a DEM. You can SAVE a route ... then much later on, go back into the route again, and experiment on a new session, and test the smooth spline tool to see what it does to your DEM ... and if you don't like what it did ... hit "Don't Save"
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