Terrain Not Too Accurate

[TheTeenageFoamer]

I use the importing terrain trick on a route to see if it would be a good choice. But when I did the terrain, it was very hilly and it dips really deep where the road bed goes, basically to the point of an unrealistic look. I just don't know how they did it so nicely on the Lafayette Division.

[artimrj]

I used the SRTM. Shuttle Radar Topo Mapping ( I think it is called).

[sumitsingh]

I tried this good method and it worked nice.

https://www.youtube.com/watch?v=-VUnFFDPu8Y

[TheTeenageFoamer]

I loaded up the terrain that Bob suggested, and this is what it looked like:

20171015221451_1.jpg

20171015221500_1.jpg

20171015221504_1.jpg

This is Delphi headed south west, right here to be exact.

delphi.jpg

I just don't think the railroad would bank a curve that much.

[gwgardner]

Use the snap-to-track tool to make that look right.

[Bananarama]

No - Snap to track has nothing to do with it - make sure to turn off snap to terrain when laying track. SRTM data is +/-30m, so you need to be prepared for some discrepancy.

If using track charts (which you should), use the elevation in the track charts (converting feet to meters) as a guide when laying rail.

[sumitsingh]

Making tracks on embankment will be a good idea.
May be some meter above ground.

Refer this real life example of Goa, India. If you load the HGT file, you won't see any terrain cut.

Also here.

[BoostedFridge]

Berkshire, there are a few things to take into consideration here.

First, congratulations for getting SRTM/DEM terrain into the game. Now welcome to the fun of building a route with it...

The higher the 'resolution' of the SRTM/DEM terrain, the easier the job you will have of knowing how to lay your tracks, and adjust your terrain to it. No matter what resolution though, none of the DEM that Railworks can handle will ever be so close to the real terrain that you won't have to make any adjustments to it.

All SRTM/DEM terrain is NOT created equal.

As Matt P mentions in the first few minutes of the video that Sumitsingh shared, there are many different 'resolutions' available from different sources on the internet.

Do you know what resolution, or site yours came from?

The site Matt used; 'viewfinder panoramas' has 3 arc second resolution. That means that the terrain height is accurate at points every 295 feet, and averaged out in between. A single track railroads roadbed is ~11 feet wide. Using 3 arc second terrain for a route, and laying the track to match that terrain will not produce remotely accurate results. You'll find that things such as cuttings, track embankments, and small grade changes just will not register at all in the terrain. Inversely, ditches, rivers, and other low points may not show up either.

1 arc second resolution is much better, but still not ideal for terrain with 'sharp' features.

In the example of your bridge near Delphi...

The 2d 'top down' picture that you posted from Google Earth does not do the real terrain any justice. ...nor does your SRTM/DEM terrain unfortunately.

Looking south from north end of Delphi bridge.jpg

Looking North to south at Delphi bridge.jpg

On both sides of the bridge the rail line is up on a steep fill or embankment. Google Earth's ground level view shows this pretty well.

Embankment north of bridge.jpg

The embankment is only 113 feet wide at its base. If you look at the information below, you can see how even with 1 arc second resolution SRTM/DEM, you would likely only get a small 'bump' in that terrain to represent the embankment after you import it into Railworks.

3 arc second = 295 feet between accurate elevation points
1 arc second = 98 feet between accurate elevation points
1/3 arc second = 32 feet between accurate elevation points
1/9 arc second = 11 feet between accurate elevation points

So does this mean that all DEM but 1/9 or 1/3 is useless? No, but the lower the resolution, the more effort and care that the route builder has to take in order to make their grades, and terrain be close to accurate. In this example, this would mean using the increase & decrease height tools to build up the embankment to track height, and lower the river to its appropriate height.

In your situation I would suggest laying your track based on a grade profile/track chart as Hack suggested. You are in luck, and this route has one available. I have linked to it below. Delphi is on pages D6 and D7. The line is climing a 0.75% grade going from north to south on either side of the bridge. PM me if you have any trouble reading the chart.

http://www.multimodalways.org/docs/railroads/companies/NS/NS%20Track%20Charts/NS%20Decatur%20Division%20Track%20Chart%201-1-1987.pdf

You will probably find that in flatter areas, the slope of your terrain, and the grade profile will match closely. In more undulating areas, I would lay your track based on the chart, and then look at Google Earth and figure out if you need to raise or lower the terrain in game to match an actual landscape feature.

It will be a pain at first, but like anything, you will get better and faster the more you work at it.

Good luck!

[TheTeenageFoamer]

Thank you for that! I guess my biggest issue is patience. I've used 3 different sites and two of them have been 1 arc second. Like you and hack said, i should just lay the track at the appropriate grade hight and go from there, I just don't really know how long to make a section of a grade before it levels out or starts getting steeper.

[BoostedFridge]

Thank you for that! I guess my biggest issue is patience. I've used 3 different sites and two of them have been 1 arc second.

Which sites have you been using? The latest and best for any DEM in the USA (and other parts of the world) is the USGS and their national map viewer. If you haven't done it already, check it out. Some guy that doesn't know much about this wrote a tutorial for the download process here :

http://railworksamerica.com/forum/viewtopic.php?f=7&t=17791

[TheTeenageFoamer]

Thank you for that! I guess my biggest issue is patience. I've used 3 different sites and two of them have been 1 arc second.

Which sites have you been using? The latest and best for any DEM in the USA (and other parts of the world) is the USGS and their national map viewer. If you haven't done it already, check it out. Some guy that doesn't know much about this wrote a tutorial for the download process here :

http://railworksamerica.com/forum/viewtopic.php?f=7&t=17791

I have used your method, Bob's method, and Matt Peddlesden's.

[RailWanderer]

The key thing to remember when doing this DEM work is that even with the tightest data, it will never be exact. So, get your bucket of fudge out and use it. I had trouble with this at first too, but after you experiment a bit with small sections to see if you can model to real world specs you will establish your own way of doing the process. I don't try to be accurate, I try to be close and I have been known to be very picky. The thing you do need to know is whenever you make changes to the grade of track, make certain you save every action you change, or you will regret spending five minutes of work and then the editor runs out of memory. Even with 1 arc second data I have never had a complete ground shape that followed the track in GE. There are some gaps in the data that cause gaps in the terrain model. Its not an exact science, and I am no expert, but I have had pretty good luck at creating convincing looking track roadbed terrain. Good luck.

[TheTeenageFoamer]

So I have imported the data and started laying track according to the track charts, but I get these huge cut outs in the ground like this:

20171026170850_1.jpg

20171026170858_1.jpg

In real life these areas are just about level with the track.
Any tips?

[RailWanderer]

So I have imported the data and started laying track according to the track charts, but I get these huge cut outs in the ground like this:

20171026170850_1.jpg

20171026170858_1.jpg

In real life these areas are just about level with the track.
Any tips?

If these cuts are not to your liking and don't fit with what you might know the trackbed to be, use the Smooth tool under the Paint Brush Tab, set it to around 20-30 brush size and use circular motions with the mouse while left click & Hold. Remember the yellow circular tool gizmo is where the action of smoothing is taking place, the white gizmo is the effective area in total. Also, experiment with the circular motions both at the top of the cut and the bottom of the cut and see the difference in smoothing.

[sumitsingh]

Hi you need to adjust cutting and embankment settings from painting terrain sub menu.