The Trainz Darjeeling Himalayan Railway Project:
First You Build a Mountain

By John D'Angelo

As I write this article, Bill Slack is virtually sitting on a very steep hill in the Himalayan Mountains waiting for a map to arrive. Rest of paragraph. Or should I say Bill is sitting on a virtual reality Himalayan hill waiting for that map! Right now he is trying to figure out the best route to continue laying 2' narrow gauge track, and he really does need that map. Hopefully, by the time I get to the end of this article, he will get the map he needs. If you're confused about all this, don't worry, we'll just go back in time a bit.

I recently wrote an article in the VR Reading Room describing the Darjeeling Himalayan Railway and stated that members of the Trainz Narrowgaugers had decided they would build a model of the DHR. That project is now officially underway and work is progressing on a number of different fronts. Models of the DHR locomotives and cars are being built, numerous buildings are being created, and track designs are being worked on. Right now we are in the midst of one of the most difficult parts of the project, and that is creating, in full scale, the entire mountain range along the route of the DHR; correctly placing the villages along the route, and placing track along the route linking the villages.

At first we thought we might try to shorten the rail distance between some villages to reduce the running time between Siliguri and Darjeeling. This would have been done by straightening certain sections of track, removing curves; but as we got further into creating the model we realized that every curve was needed to traverse the steep hills and keep the grades between the villages within reason. We now estimate the model's running time, when completed, will closely match the actual running time of 5 to 8 hours depending on the station stops used.

Usually when a model railroader creates a layout, he first lays the track and then builds up the terrain. The terrain of most model railroads is usually not an exact model of the surrounding countryside and is normally shaped by the builder for the best effect.

For the Trainz Darjeeling Himalayan Railway, the decision was made to create the model by building the terrain to scale and placing the village positions using detailed maps or their latitude and longitude coordinates, then laying the main line to link the villages. In order to do this, we needed our expert surveyor, Bill Slack.


Bill Slack.

Creating the Landscape

When you attempt to build an accurate 3D model of a geographical area for Trainz you need to access different programs and sources of information, then work with them to create the model you will run your trains on.

It is an involved process, so I asked Bill if he could describe to me the process involved. Bill not only described this process, he also wrote a detailed tutorial and sent me screen shots to illustrate some steps!

The documentation he provided is extensive enough to warrant being made into a separate tutorial that can be downloaded on its own. The tutorial has now been written, and is available here at the VR Reading Room. For the purposes of this article I will give you the highlights of Bill's description of the process.

Basically, there are four components to the process of creating a 3D landscape model for use in Trainz: DEM, MicroDEM, a photo editing tool such as Paint Shop Pro, and HOG which stands for Hand of God.

DEM. DEM stands for Digital Elevation Model. A DEM source is a place where you can download the DEM mapping data you need to create the model. There are sources on the Internet where freeware and payware downloads of DEM data can be made. Among these sources are:

NASA: ftp://e0srp01u.ecs.nasa.gov

The NASA site is for FTP (File Transfer Protocol) downloads, and you will have to navigate through the menus to find the files you may want.

GIS Data Depot: http://data.geocomm.com
MapMart: http://mapmart.com
Terrainmap.com: http://www.terrainmap.com

The Terrainmap site has an extensive amount of information about using DEM files and has numerous links to map data sources. I have found it to be an excellent choice for getting DEM related gear.

MicroDEM. OK.... The download is successful and you have a DEM file in your hot little hands, now what do you do with it? You take that file and MicroDEM it. MicroDEM is a program that will work with DEM files.

The MicroDEM website is: http://www.usna.edu/Users/oceano/pguth/website/microdem.htm The program is free. You then open the DEM file into MicroDEM and work with it.

Graphics Conversion. Once the file has been worked on in MicroDEM you copy the result into your Windows clipboard and then open up your graphics program. (Bill uses the free version of Adobe Photoshop for this step.) Move the file from the clipboard into the graphics program. The file will be converted into a TGA file.

HOG. The final step is to take the completed TGA file and move it into HOG. HOG is a program that converts the TGA file into a .GND file for use in Trainz. This .GND file is a 3D terrain file that can be called up in Trainz Surveyor for the adding of textures, track and buildings.

The HOG program is available from Trainz Luvr at: http://trainzluvr.net

Search for the HOG file by searching the keyword "HOG". When you look at the HOG files available for download you will see a series of ZIP files. The different files are modifications of the basic file HOG100.zip. They all are to be added to the basic file. Download and install HOG100, then download and install the higher number files in ascending order. You then create a basic route, substitute the .GND file you created with HOG for the .GND file in the basic route. When you open the route in Surveyor you should see the new 3D model of the terrain and be able to work with it.

Remember, this is only an overview of the operation. For detailed information about the steps involved, I recommend you read the tutorial by Bill.

Modeling the DHR

In the case of the model of the Darjeeling Himalayan Railway, after all those steps, Bill has taken this contour map (right) and turned it into this base model (below) in Trainz Surveyor.

The view here is only a portion of the entire model, but I think you can see that this is VERY difficult country to lay tracks across!





Placing the Villages. The next step Bill faced was the placement of the villages on the newly created 3D map in Surveyor. Geographical information such as the latitude, longitude and altitude of the villages was very hard to find. The railroad is located in the Himalayan hills that divide India from Nepal. The villages along the route are very small, and because of this, detailed geographical information about them is not easy to find. A large number of the villages had no latitude and longitude coordinates available from Internet sources. The actual maps available were sketchy in detail, and some actually placed villages in the wrong locations!

Physically working track across the route was also very difficult because the hills were so steep that when in Surveyor mode, Bill’s view up out of valleys was very limited, making it difficult to for him get a feel for where he was headed.

We even entertained the idea of using the drivable Cessna with Mike10’s special single wire track to give us a view from overhead of the area being worked on.

I experimented with using the Cessna and laying a large red circle on the route to mark the villages. This helped me to see the overall route from well above the terrain, and the villages would be quite visible when using the mapview option.


Using the Cessna as a scouting tool.

Bill was able to continue his work without using the Cessna or red city marks idea, but I figured it might good to illustrate how it would have worked. The terrain that you see is an early version that has been replaced by a better rendition.

Ready to Roll

I have just received an email from Bill; he has finally received detailed mapping information that will help him greatly, and he can continue laying track. In addition, Peter Pardoe-Matthews has ordered a highly detailed map of the Darjeeling Himalayan Railway from the Darjeeling Himalayan Railway Society’s online store (www.dhrs.org.uk/sales) and that has been mailed to Bill. Right now, things are really looking good for Bill and his track crew as they work northward towards Darjeeling.

Darjeeling or bust!

John

Article and screen shots ©2006 John D’Angelo. All rights reserved.