In reality you would set the height at first and then place the railtrack. In LOTUS you may build the railtrack first. Espacially when making the first experience in the Map Editor the order of constructing a rail system like in reality will cause problems, if you want to change the terrain afterwards.
The method is simple: You build the railtrack somewhere on the terrain, check the rails in the simulation afterwards and place the subgrades parallel to the rails. The last step is to build the landscape of course.
This is the topside view of the rails we use for this tutorial:
The highlighted part will be set a little bit higher than the rest. Because. Reasons.
Now we set the height:
You'll see that the terrain adjusts its height around the railtracks, so we need a subgrade.
But at first we build a second that. To do so we use the parallel function with a shift of 3.2 m:
3 Test drive
This is the time to test drive the rails. In fact we don't want to change the height of the rails afterwards!
Well this looks promising I guess. If the slope should be more steep, this is the last time we should change the rails in the Map Editor. But in this case the rails are fine.
Now we will place the subgrades.
Keep an eye on the relative height! When using the grooved rails the subgrades should be 0.15 m above the rails at the height of the curbstones. The rails itself are situated on the lower height, where the cars are driving. If you are using gravel tracks the Z value you use is -0.25 m. Otherwise you wont see the rails ingame.
The method we are using is like:
1. Change to railtracks on the left
2. Select the rails in the secondary mode (while holding [Shift] + [Ctrl])
3. Go to terrain on the left side
4. Set the Z value to 0.15
5. Set the width of the subgrades to 50 m because we want to place buildings near the rails.
6. Click on "New parallel subgrades" and set the shift to the half of the distance between the two rails - in this case 1.6. Depending on the rails you selective the value is either positive or negative. When using the track on the right side, we have to use -1.6.
As you can see the subgrade match the railtracks we tested ingame before.
And after building the street everything looks fine.
You've got any problems?
There might be problems with subgrades, when they are not connected logically to each other. If they do so select both subgrades, hit and calculate the terrain again().