First Experience of TransDEM

[simtrain]

I brought TransDEM, downloaded it, installed it, loaded the Trainz textures, read the manual in a mans way, e.g. glanced at most of it, did the tutorials (which were excellent... they must have been because I could do them!), then thought I'd jump straight in and have a go myself

I went to OS and downloaded the DEM files, then following the tutorial, but using MY area that I want to do, I tried using the method of getting my maps from Google Earth, all went well until I tried to put DEM and map together in TransDEM.... Er something came up about the map have 1 pixel to something or other too many. Mmmm ths didn't happen with the tutorial, so I tried several times with the saved map, still no luck, so I went from the begining....still no luck, so last resort, read that part of the manual again and again, it didn't mention my problem.

I must stress that anything that the program didn't do was down to ME, TransDEM is at no fault whatsoever, Going by how well the tutorials went, and the results in Trainz, TransDEM is the next best thing to sliced bread!!

Anyway onward and upward.

Next I went out a brought the OS maps for the route I want to do. I purchased the Landranger version 1:50 000 scale.

Right, get the map of the begining of my route, find the right section, and boot up the scanner. Scanned the section, booted up TransDEM, followed the tutorial subsituting thier DEM's and Map's for mine.

All went well until I Georeferenced raster map to UTM co-ordinates. Several times the map changed to a spiral, other attempts, it disappeared. Oh dear, back to the manuals!

On flicking through I came to a part about scanning, and the example of A0 sizes and DPI.... Mmmmm ok, I opened my photo editing package, and changed the DPI to 75DPI, back to TransDEM, followed the procedure, and Bob's your Aunty it worked!!

Right boot up Trainz Content Manager, imported the route, then into Trainz, and there it was, the begining of my route..... Only one problem 1km equals around 12km in Trainz.... Back to the manual!!

Again, I'll stress that it's my lack of knowledge and not reading the manual (and believe me I don't think you need much to master TransDEM) that is at fault, I'll keep you posted as to how I get on, and whilst you wait, why not purchase a copy for yourself, and see how much better this programme can make your routes, the difference is astounding!!

Simtrain aka Steve

 

[geophil]

Steve, O/S Landranger and Explorer maps are also available online, one of the hidden gemstones. This could save some time. You probably already imported the settings for the map tile services. Pick MS Virtual Earth (known as MS Bing Maps today) and select tile type "Other 1". Zooming in to the right level will reveal O/S topo maps 1:50,000 and 1:25,000. There is also the historic section under its own provider name. "Other 1" there points to the 1:25,000 series from the 1950s/60s.

 

[cascaderailroad]

You sound like me :hehe: allot ... I sort of got the understanding of the program, but I have so much more to learn about georeferencing maps, and saving them onto a Transdem Trainz DEM

 

[simtrain]

Geophil - I'll have a play with MTS, thank you!
Cascaderailroad - Got to admit I'm having fun having to use my one and only braincell, TransDEM is a very powerful tool, only had it a day or so, but enjoying it thoroughly

 

[steamboateng]

Georeferencing in TransDEM took me the longest time to get a handle on. The obvious, I finally perceived, was obscured in learning a new vocabulary. Rather than loose myself in a the myriad of ellipsoid algorithms and geo-spherical mumbo-jumbo, it dawned on me to approach it all in linear terms, much like the Cartesian coordinates we learn in high school math. The mystery was solved right then and there, in the very first DEM download.
DEM data by definition contains vertical height data, obviously....................the unspoken obvious part,...............well, it also contains geo-coordinate data, inherently, to define the location of the vertical element. Thus, right from the start, a simple DEM map generated in TransDEM internally stores all the relevant height data, along with a corresponding geographic location, defined in UTM coordinates.
Once the DEM map is generated, georeferencing is, in practical terms, no more than matching a map or snippet, defined by its four corner geogrphic coordinates, to the cordinates defined within the DEM. It's clear that any raster image, Google Earth Data, USGS topo map or whatever, can be georeferenced to the DEM, by inputting its correct coordinate data.

 

[Vern]

The only thing to watch is that sometimes the maps can be slightly misaligned with the DEM data. Not so much a problem with the UK these days but I have recently been creating a few experimental Irish routes. The best DEM I can find is 60m Viewfinder and Open Street Map is considerably "off" with rivers up the side of hills etc. I had slightly more success doing it longhand by taking clippings from the Irish OS on-line service, assembling in Paint Shop Pro then georeferencing in Transdem. Still not perfect but enough to make adjustment by Mark One eyeball.

 

[geophil]

... creating a few experimental Irish routes. The best DEM I can find is 60m Viewfinder and Open Street Map is considerably "off" with rivers up the side of hills etc. I had slightly more success doing it longhand by taking clippings from the Irish OS on-line service, assembling in Paint Shop Pro then georeferencing in Transdem.

In this case I would assume that the cause of the misalignment lies in the Viewfinder Panorama DEM data.

 

[cascaderailroad]

I was wondering if the Newest version of Transdem is radically more simple to use than older versions of Transdem ? Where you just sort of "plop" a topo map into the DEM, and it self georeferences, and places itself ?

 

[steamboateng]

This is true with downloaded 'Historical' USGS topo maps in geo-pdf format. Dr. Z did a fine job automating margin clipping to a mouse click. Georeference data is inherent in the downloaded map data in this format. The manual explains all.
Some Map servers download georeference coordinates with the map(s).

 

[JCitron]

I've run into this horizontal shift a few times now with topographic maps downloaded from either MS or the National Map Server. They are off by 5 or 10 meters which is enough to throw roads, rail ROW, rivers, etc. off the mark. These anomalies occur it appears when maps have been stitched together or pasted together for scanning. On one of the downloads, there was a strip of numbers and letters along with bits of words as though the maps were taped together along a page seam but didn't do a good job at it.

John

 

[Lots_Trains]

I was wondering if the Newest version of Transdem is radically more simple to use than older versions of Transdem ? Where you just sort of "plop" a topo map into the DEM, and it self georeferences, and places itself ?

Yes its an amazing peice of kit, its revolutionary, what it does it reads and scans you mind to find out exactly what you want then goes out gets all the relevant data in all the required formats and plops it on the DEM, it then lays the track, signals, buildings and roads in the right place. However the automatic session generator is still been worked on, its ability to scan small brains is not working properly.

Seriously I thought TransDem was really simple to use.

Cheers

Lots :wave:

 

[cascaderailroad]

Seriously ... It scans your mind ? I once had my bwain scanned ... and all that showed up was "Gray Matter" :hehe:

I was asking whether there is a radical improvement, and automatic georeferencing in the New Version of Transdem ... as opposed to the manual georeferencing of the older version ?

I always had to use the 2 point manual georeferencing input table, which was rather tedious.

 

[geophil]

I just went through my internal CVS and Subversion logs:

• 3 + 1 point georeferencing was implemented in Feb 2004
• 2 point corner georef added in Nov 2005
• Google Earth semi-automatic georef with kmz/kml file in May 2006, improved in Sep 2006, auto-detected kmz/kml file in Apr 2013
• WMS auto georef in Sep 2006
• Map tile services auto-georef in Sep 2007
• GeoTIFF for raster maps, auto-georef in Jul 2009
• Ultimate manual georeferencing with triangular irregular network in Sep 2012
• ESRI world file auto-georef in Oct 2011 and improved in Apr 2013
• GeoPDF in May 2013

Forgot anything?

 

[laika]

Its a great piece of sofware and a must buy when you want to make a prototipical route as far as Trainz can make it possible(well i never say 100% prototipical because Trainz is a sim and not RL). I bought the last version and since version 1.5 its a huge difference in better images and its faster and easy to learn when you use Google Earth like me. I just made my complete Transdem map(aprrox 150 km) inculding all google earth information i need in just a couple of day's. So i,m ready now for my last but huge map the RER E line in Paris including Saint Lazare. It will keep me busy for a long time.

And what a big surprise the UTM's with the Google earth are 3d and will be places in a layer automatic. Well thats just the way i need.

Thanks Roland