TransDEM Forum

Does anyone have any recommendations for United States sources for data (dems, vector data, etc.). I know that there are tutorials that are out there which have suggestions for sources for different countries, but I know me, and a lot of other people who are new to Transdem, are looking for CURRENT sources for United States data, and are having a really hard time. I thought I might make this thread to help me, and others, find sources for Transdem compatible data.
Bryson Sleppy
North West Ohio Rail Enthusiests

Thank you for the quick reply! I was wondering if instead of using vector data, could you use Google Earth in the way that this tutorial shows? (The tutorial is a pdf in the zip file at the bottom of the page): http://www.dhobh.net/trainz/TransDEM/GroundTextures.htm

You will need some simple vectors in any case. Polylines, marking the course of your railway line, will serve as a baseboard creation filter. Only those baseboards in vicinity of the created will be created, saving hundreds or even thousands of largely waste land boards.

For finding your way around in the DEM terrain you have basically two options: (topo) maps or ortho-imagery. Route builders less familiar with topographic maps go for ortho photos but you will need higher resolution/larger scale than with a topo map. And the way Trainz handles ground textures we face a technical limitation: Maximum usable resolution is 1 pixel per 5 or 10 m. That's good for a topo map 1:25,000 but less so for an aerial image. If you really want to use aerial images, then you better create so-called 3D UTM tiles in TransDEM, which are ordinary Trainz objects serving as high-res texture carriers. TransDEM will create those tiles for you, paint them with your ortho-imagery and also place them into your route. The Muengsten tutorial in the TransDEM Trainz manual shows both options, but uses a large scale 1:5000 map instead of ortho photos.

The tutorial also indicates that you can combine topo maps with ortho-imagery: topo maps as ground textures, ortho images with UTM tiles. You can do it the other way round, too, but in that case the ortho-images are probably intended to become the final ground textures. See here for an example: http://forum.transdem.de/viewtopic.php?f=2&t=295

TransDEM 2.5 introduced a new ground texture set of its own, 128 unique colours, optimized for aerial photography. I'd prefer that to ModelerMJ's earlier approach which you mentioned.

I have spent some time searching, and can't find any vectors for the US....
Any help is much appreciated!

Did you try the National Map Viewer for vector data as suggested in my previous post?

geophil wrote:Vectors: National Map Viewer again, at least theoretically. Vector data available as shapes files. However, the railroad layer may be missing. It's only been added in new editions from spring 2013 onwards.

Is the railroad layer available for your project area?

Then again:

geophil wrote:The easiest may be to trace the lines yourself, using the built-in editor in TransDEM.

Even with the 1:24 US topo vector map the scale will be too small to deliver more than a coarse sketch of the track, no more detail than on the 1:24k raster maps.

If you are really into vector data pre-processing, you can also try Open Street Map, see here: Open Street Map Vector Data in TransDEM with JOSM

Here is the problem I'm having...
I download the zip file they give me after for the shapefiles from the National Map Viewer "Transportation" tab as shown here:


And then when I install any of these, I get this error:

I'm doing the Northwest Ohio area btw.

Is the download intact? What's the size of that particular shape file? A corrupt file could produce this error.

The shapefile zip is 29.3 MB.