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alco_power
July 7th, 2007, 11:33 PM
Hi Everyone, i know i have asked this a long time ago on the old forums but obviously the answer i cant find now,
Can someone please shed some light on how to OBTAIN DEM's and and how to import them etc. I was working on a route for two years and my hard drive crashed so now its all gone ! 2 years work. So i want to start again but use DEM's now so its more accurate as such - SO how can i get DEM's for my route - Murwillumbah NSW to Newcastle.. or parts at a time, can you buy them? or...?
Thanks so much ! :)

Alco_power:o

Jerker
July 8th, 2007, 10:09 AM
G'day alco_power,

Newcastle to Murwillumbah??? It takes the Murwillumbah XPT 10 hours 40 minutes to make that run. Surely you don't expect people to 'run' a train in the game for that length of time in one sitting? I took a quick look at my archives and have concluded that I did not do the original route of which you speak, so I can only conclude that this is a new request or you made the original yourself. If that is the case, then you ought to know that the SRTM data is freely available through the NASA website...

ftp://e0srp01u.ecs.nasa.gov/srtm/version2/SRTM3

...on the other hand, if the original was not created using DEM, then I might be able to assist you. I would, however, suggest that you 'lower your expectations' and reduce the size of the route to something a little more manageable. I have found that the best results are obtained when the area covered is about 100 kilometers (with some dependency upon the direction the route 'takes' - if it runs directly North/South or East/West, then a little more can be 'gained' but if it runs 'diagonally', this is about the limit). 100 kilometers is about 2 hours worth of game time which is generally the accepted length for the majority of people ("concentration span" and all that sort of thing). Let me know your thoughts and we can discuss things further...

Jerker {:)}

alco_power
July 9th, 2007, 05:55 AM
G'day alco_power,

Newcastle to Murwillumbah??? It takes the Murwillumbah XPT 10 hours 40 minutes to make that run. Surely you don't expect people to 'run' a train in the game for that length of time in one sitting? I took a quick look at my archives and have concluded that I did not do the original route of which you speak, so I can only conclude that this is a new request or you made the original yourself. If that is the case, then you ought to know that the SRTM data is freely available through the NASA website...

ftp://e0srp01u.ecs.nasa.gov/srtm/version2/SRTM3

...on the other hand, if the original was not created using DEM, then I might be able to assist you. I would, however, suggest that you 'lower your expectations' and reduce the size of the route to something a little more manageable. I have found that the best results are obtained when the area covered is about 100 kilometers (with some dependency upon the direction the route 'takes' - if it runs directly North/South or East/West, then a little more can be 'gained' but if it runs 'diagonally', this is about the limit). 100 kilometers is about 2 hours worth of game time which is generally the accepted length for the majority of people ("concentration span" and all that sort of thing). Let me know your thoughts and we can discuss things further...

Jerker {:)}


hey mate
thanks for replying to me, since then i found some info on transdem but still a bit confused. What i was hopeing to do , was cover sections at a time

for example: Murwillumbah - Casino or lismore,
and then another section casino to grafton etc. The only reason why i want the DEM data etc is so i can get the terrain and basic direction of the track I have all the track diagrams for each station and also the distances etc. The original route that i did i just guessed lol and used my imagination, was a great route but i started it prior to the hype of DEM etc. How does one view the extracted files from the nasa site, file format is .hgt - do i just download them all and search for the region?

Another few questions for you if thats ok
1) can i do section at a time, and then import the next part after i finish it? as i would eventually like to do as much as i can at least down past coffs harbour/sawtell area - as hills around that region are so difficult to find information on
2) are their any guides on net that show how to import this stuff into trains :( i feel really stupid asking all this stuff - anything about real trains i know lol .
3) do you have to automatically "extend" all the baseboards prior to importing the dems in or does it calculate and do that automatically
4) do i need to purchase transdem?

THANKS so much i appreciate your advise and help

geophil
July 9th, 2007, 08:09 AM
Have a look into the TransDEM manuals and the tutorials in particular, once the software has arrived. That should answer most of your questions.

Creating the basic Trainz terrain and overlaying it with a topo-map-based ground texture is a fairly automated process for regions such as NSW. The only limitation to the size of the route is memory consumption. But if you do this in steps, module by module, it should work.

geophil

Jerker
July 12th, 2007, 08:52 PM
G'day alco_power,

If you wish to cover the entire distance between Murwillumbah and Newcastle, then doing it in sections is the best way to do so. I have successfully recreated the distance between Brisbane and Toowoomba, this way. It has to be kept in mind that limitations still apply (the Toowoomba route came in six parts) and that TransDEM has a limit of 32 MBytes for any files that must be georeferenced, over and above this.

As geophil (the creator of TransDEM suggests, read through the freely available TransDEM manual (and look at the tutorial on how to create a route for an English layout) and it should all come together. Between the two of us (geophil and myself), we should be able to steer you in the right direction..

Jerker {:)}

nbrettoner
July 12th, 2007, 09:44 PM
Hello Geophil, Jerker & Alco_Power,

Just wanted to say "G'day" at this point.
I'm finding this topic becoming (for me) more interesting.

Jerker you will be aware of Craig (Seeseeme) & my project; the
"Narrandera_Tocumwal Branch-Line", & some of what that may entail.

I notice that there is a 'semi-automatic' Google Earth referencing functionality with TransDem??.
This I am very interested in, as at present on the DHR Project I find GE is invaluable, for what I am doing, & I will be using GE in our project too.

Apologies for jumping in here Alco_Power

Ghostryder
July 13th, 2007, 01:28 AM
Alco power

what details and data do you have for the coffs harbour area ? let me know will see what i can do. as most of what you need is not far from my current location.

Cheers

Ghosty

geophil
July 13th, 2007, 02:22 AM
I notice that there is a 'semi-automatic' Google Earth referencing functionality with TransDem??.


It works like this: In Google Earth you create a placemark, then you save screenshot and placemark and open both in TransDEM. TransDEM processes the placemark data to georeference the screenshot, i.e to scale, rotate and position it at the correct location. At a later stage you let TransDEM create texture carrier objects, called UTM tiles (other incarnations are known as "Base Maps"). These UTM tiles will be painted with the Google Earth imagery and then placed right on the spot in the Trainz terrain.

There is a catch, though. For this to work, the Trainz terrain must have "absolute" coordinates. For this purpose TransDEM seizes the Trainz World Origin object to leave its coordinate footprint. It sets the world origin when it generates DEM based terrain in the first place, well aligned with the UTM grid.

You may be able to merge HOG-based Trainz terrain with TransDEM Trainz terrain, provided the HOG module is to scale, in UTM projection and reasonably aligned with UTM North. There will be a horizontal shift error between the modules of up to 360 m, half a baseboard size. Bridging that gap is up to the ability of the terrain sculptur. ;)

geophil

nbrettoner
July 13th, 2007, 03:42 AM
Hi Geophil,

Many thanks for that exciting explanation.
Exciting (to me) as it shows a better way;
than manually processing dozens of base-maps, which I have done so far.

Once Craig & I have progressed a little further with the route, is it possible to
later on 'add in' this GE functionality?.
Or do we need to set this up right at the start of the DEM mapping procedure?.
Craig presently is getting things ready for Stryker to help us with his 'cleverness'.
Neither Craig nor especially I, are experienced enough to as yet 'have a go'.
But hopefully this will change.

Many thanks for your assistance, great programming & generosity.

:)

geophil
July 13th, 2007, 07:08 AM
... is it possible to
later on 'add in' this GE functionality?.
Or do we need to set this up right at the start of the DEM mapping procedure?...


Basically, these UTM tiles with GE textures can be added at any time. However, as I said before, they rely on the absolute coordinate origin which must be present in the Trainz gnd file. That origin is stored in the Trainz World Origin object, manipulated by TransDEM.

Any Trainz terrain created with TransDEM will be set-up correctly.

Hog-generated terrain, fulfilling preconditions listed in my previous post (UTM, aligned with the north axis, to scale), may be merged into a TransDEM generated module and receive a World Origin through merging. A certain positioning error will remain, though, as HOG terrain is based on relative coordinates.

In a slightly different operation mode, TransDEM can create properly textured UTM tiles without placing them into the terrain automatically, leaving that task to the route builder. This way UTM tiles can be added to any Trainz map. All tiles are aligned with the UTM grid and each tile is denoted by its UTM coordinates.

geophil

alco_power
July 13th, 2007, 06:08 PM
G'day alco_power,

If you wish to cover the entire distance between Murwillumbah and Newcastle, then doing it in sections is the best way to do so. I have successfully recreated the distance between Brisbane and Toowoomba, this way. It has to be kept in mind that limitations still apply (the Toowoomba route came in six parts) and that TransDEM has a limit of 32 MBytes for any files that must be georeferenced, over and above this.

As geophil (the creator of TransDEM suggests, read through the freely available TransDEM manual (and look at the tutorial on how to create a route for an English layout) and it should all come together. Between the two of us (geophil and myself), we should be able to steer you in the right direction..

Jerker {:)}

oh gee. i must be stupid.

Well i brought TransDEM quickly and easily and installed and everything seems to work fine. The documentation is brilliant and i get the basic idea. However i have hit a brick wall and i believe that would be my fault ! lol
and its gotten to the point where i dont know what to do now.
ok this is what i did.

I went to the NASA FTP site and i downloaded ALL The Zip Files off that site, and extracted them all into one folder. - i ASSUMED that the FILENAMES ie: S28E153.hgt? is the Long/Lat description? in degrees? anyway. so i used Google Earth and started with Murwillumbah and got the co'ordinates or degrees whatever they are called and then opened the "SRTM" file that is closest to the long/lat information i got from google earth.
and this is what i got:

http://www.quiksilverboy.com/trainz/shot1.gif

Now, this is whats confusing me, I have no idea if the green area on the right hand side is water or if its land or what ever? i zoom in as much as i can, and i just dont know HOW to identify where exactly im looking at. ALL the maps from that nasa server look like this. So i started zooming in and used the pointer button to select an area and then import into trains which i learnt from the tutorial. And sure enough, it was very "hilly" or "mountainous" but i still dont know where it is as i cant seem to get the scale right or find the maps to import.
I guess essentially all i want to do from TransDEM is get the mountains/hills/land etc and maybe use a google earth UTM file thing someone to overlay so so i can "see" where i am.. and then i can lay the track myself as i dont mind doing that..

ouch i dunno what to do now.
PS; thanks for advice !!!!!!!!

seeseeme
July 13th, 2007, 06:30 PM
Hi Geophil,

Many thanks for that exciting explanation.
Exciting (to me) as it shows a better way;
than manually processing dozens of base-maps, which I have done so far.

Once Craig & I have progressed a little further with the route, is it possible to
later on 'add in' this GE functionality?.
Or do we need to set this up right at the start of the DEM mapping procedure?.
Craig presently is getting things ready for Stryker to help us with his 'cleverness'.
Neither Craig nor especially I, are experienced enough to as yet 'have a go'.
But hopefully this will change.

Many thanks for your assistance, great programming & generosity.

:)
I think you meant Jerker here Noel. I have looked at this program before but thought it may be too difficult to learn and then apply it to a particular area. There are many things/terms that I simply do not understand.

As suggested though I will look at the tutorial and see if my brain get come to terms with the process :hehe:

I still think the help of Jerker will be needed.

Craig
:):):)

TORANA
July 13th, 2007, 08:07 PM
Hi,
I just noticed your map,

looks like Brisbane to me, that green stuff would be Moreton bay
and they look like the islands of North Stradbroke & Moreton.

Anyway, While I'm here i was wondering, could somebody help me?

I would like to do 2 or maybe 3 part layout with an option for 4.
Bowen to Ayr & Ayr to Townsville, in North Queensland,
both maybe a little bit over 100km's in length.

could move where they would merge to south of Ayr to shorten Bowen to Ayr as it would be the longer section.

An a separate map of the Burdekin's 3 sugarcane mills, for the 2ft lovers.
are these maps available??

I would love to bring all those sugarcane feilds to life in trainz.
I have made a non protypical layout which i have put a lot of effort into, would like to see how the DEM looks.

Cheers,
Torana. :)

seeseeme
July 13th, 2007, 08:26 PM
Hi,
I just noticed your map,

looks like Brisbane to me, that green stuff would be Moreton bay
and they look like the islands of North Stradbroke & Moreton.

Anyway, While I'm here i was wondering, could somebody help me?

I would like to do 2 or maybe 3 part layout with an option for 4.
Bowen to Ayr & Ayr to Townsville, in North Queensland,
both maybe a little bit over 100km's in length.

could move where they would merge to south of Ayr to shorten Bowen to Ayr as it would be the longer section.

An a separate map of the Burdekin's 3 sugarcane mills, for the 2ft lovers.
are these maps available??

I would love to bring all those sugarcane feilds to life in trainz.
I have made a non protypical layout which i have put a lot of effort into, would like to see how the DEM looks.

Cheers,
Torana. :)
Would you have any use of a Cane Train or have you found one already :hehe: .

I saw a site the other day where there are some :hehe: that are not on the DLS .... well to my knowledge.

Craig
:):):)

TORANA
July 13th, 2007, 08:33 PM
yes thanks,

But if it shagsters i have it

Cheers,
Torana. :)

alco_power
July 13th, 2007, 08:40 PM
Hi,
I just noticed your map,

looks like Brisbane to me, that green stuff would be Moreton bay
and they look like the islands of North Stradbroke & Moreton.

Anyway, While I'm here i was wondering, could somebody help me?

I would like to do 2 or maybe 3 part layout with an option for 4.
Bowen to Ayr & Ayr to Townsville, in North Queensland,
both maybe a little bit over 100km's in length.

could move where they would merge to south of Ayr to shorten Bowen to Ayr as it would be the longer section.

An a separate map of the Burdekin's 3 sugarcane mills, for the 2ft lovers.
are these maps available??

I would love to bring all those sugarcane feilds to life in trainz.
I have made a non protypical layout which i have put a lot of effort into, would like to see how the DEM looks.

Cheers,
Torana. :)
i agree - sugar cane is so beautiful ! :) hence why i picked northern rivers to do my route

seeseeme
July 13th, 2007, 08:57 PM
yes thanks,

But if it shagsters i have it

Cheers,
Torana. :)
It is actually, I was testing these for him and had forgotten all about them until I was checking my list of "Favourites" sites.

Craig
:):):)

nbrettoner
July 13th, 2007, 09:12 PM
I think you meant Jerker here Noel. I have looked at this program before but thought it may be too difficult to learn and then apply it to a particular area. There are many things/terms that I simply do not understand.

As suggested though I will look at the tutorial and see if my brain get come to terms with the process :hehe:

I still think the help of Jerker will be needed.

Craig
:):):)

Hi Craig & Jerker,

Yes your right & Jerker I do apologize for getting your name wrong! :udrool:

And like Craig, I too am apprehensive at tackling TransDem right now.
So yes please Jerker, we will need your help.

Do you have any comments regarding doing the Google Earth link-up at the same time??.

:)

geophil
July 14th, 2007, 02:13 AM
- i ASSUMED that the FILENAMES ie: S28E153.hgt? is the Long/Lat description? in degrees? anyway. so i used Google Earth and started with Murwillumbah and got the co'ordinates or degrees whatever they are called and then opened the "SRTM" file that is closest to the long/lat information i got from google earth.


Hi alco_power,

about the only time you need do deal with coordinates is when you try to bring together DEM and maps or Googele Earh imagery. But those people who invented latitude and longitude were probably Europeans. They have made it a little bit more complicated for the Australians (and the Americans). :eek:

Latitudes range from -90 to +90 degrees, longitudes from -180 to +180.
Negative latitudes are in the southern hemisphere and marked "S" in SRTM. But they still are negative values (likewise with longitudes, negative west of Greenwich). SRTM file names always denote the south-west corner of the DEM.

With the negative values in mind, SRTM file S28E153.hgt covers lat -28 to -27 and long +153 to +154

Murwillumbah is at lat -28.3 long 153.4. This will be SRTM DEM file S29E153.hgt, one down.

geophil

TORANA
July 15th, 2007, 08:48 AM
Hi,
I just noticed your map,

looks like Brisbane to me, that green stuff would be Moreton bay
and they look like the islands of North Stradbroke & Moreton.

Anyway, While I'm here i was wondering, could somebody help me?

I would like to do 2 or maybe 3 part layout with an option for 4.
Bowen to Ayr & Ayr to Townsville, in North Queensland,
both maybe a little bit over 100km's in length.

could move where they would merge to south of Ayr to shorten Bowen to Ayr as it would be the longer section.

An a separate map of the Burdekin's 3 sugarcane mills, for the 2ft lovers.
are these maps available??

I would love to bring all those sugarcane feilds to life in trainz.
I have made a non protypical layout which i have put a lot of effort into, would like to see how the DEM looks.

Cheers,
Torana. :)

Could somebody answer this question at all, thanks.
just want to know if they are available,
and how do i obtain them?

Cheers,
Torana. :)

seeseeme
July 15th, 2007, 06:03 PM
Could somebody answer this question at all, thanks.
just want to know if they are available,
and how do i obtain them?

Cheers,
Torana. :)
Hi Torana, I have not seen any DEM files for the area you mention. In fact I have not seen many for any of Australia. I know a few people have created there own and then uploaded them to the DLS but these have been for NSW.

Craig
:):):)

TORANA
July 16th, 2007, 12:06 AM
Thanks Seeseeme,

I guess it was another pipe dream of mine.

oh well, would have been nice. :(

If anybody makes these
please let me know.

Cheers,
Torana. :)

Jerker
July 16th, 2007, 02:20 AM
G'day Torana,

Your ideas are no pipe dream! I am quite capable of creating the route you wish and making it available to you. You may have noticed that my 'avatar notice' reads "Australian DEM creator" - it does this for a very good reason. The only 'obstacle' to any project associated with Queensland's railways is the shear distances involved as espoused above with the route being sought by alco-power. I have not looked at the scope of your request yet (having only just 'found' your addition to this thread. Give me a chance to do that and I will get back to you as soon as possible.

Craig and Noel,

I can do anything that geophil describes above using TranDEM (now that I am the proud owner of a full working copy, myself), although it may take me some time to do so, as I still have the 'learning curve' to transcend).

Jerker {:)}

nbrettoner
July 16th, 2007, 05:06 AM
Hi Jerker,

Thank you for your contagious optimism!
I believe you can too. :)

Craig & I have heaps yet to do, so while your learning
the 'advanced ins & outs' etc, we can busy ourselves with all sorts.

It will be great to finally have the DEM data sorted, & be able to
get into the 'meaty-bits' of the route itself.
However it's important for the route to be right.
So I don't mind waiting a bit longer.

Thanks Jerker, & Geophil, for making all this possible.

:)

TORANA
July 16th, 2007, 06:30 AM
G'day Jerker,

Thanks, that's great news

I mainly would like The Burdekin Sugarcane railways.
This is alot of rail, 4 Sugarcane mills, Ayr, Home hill, Brandon & Giru
all the way up river to Millaroo & Dalbeg,
from south of Home Hill to north of Giru.

I think Bowen to Townsville would be to much.
it would have to to be in at least 3 or 4 stages
I'm all ready making the route not to scale & still a long way off.
Up to you mate.

Cheers,
Torana. :)

seeseeme
July 16th, 2007, 07:37 PM
G'day alco_power,

If you wish to cover the entire distance between Murwillumbah and Newcastle, then doing it in sections is the best way to do so. I have successfully recreated the distance between Brisbane and Toowoomba, this way. It has to be kept in mind that limitations still apply (the Toowoomba route came in six parts) and that TransDEM has a limit of 32 MBytes for any files that must be georeferenced, over and above this.

As geophil (the creator of TransDEM suggests, read through the freely available TransDEM manual (and look at the tutorial on how to create a route for an English layout) and it should all come together. Between the two of us (geophil and myself), we should be able to steer you in the right direction..

Jerker {:)}
Hi Jerker and geophil, I am almost finished colouring in the required files or removing the unwanted colours that are not needed.

I am curious about the mention of the file size. I have 2 files for you Jerker and in there Paint Shop Pro formate they are well over the 32MB size you mention. Will this then be a problem and should I try to break it down. This may only be due to the format I have saved them in as well, I do not know what format is required by TransDEM.

Craig
:):):)

geophil
July 17th, 2007, 02:01 AM
For DEMs TransDEM doesn't need any manual data preparation. Simply download the SRTM zips from the NASA ftp site and open them in TransDEM. You can directly create Trainz terrain from that - just a few mouse clicks -, if you don't want to overlay any topographical maps.

For the Darjeeling project, a few months ago I have posted some links to older US military maps of India (1:250000, IIRC). These can be used as a ground texture for some very basic orientation.

For details of the Darjeeling area Google Earth seems to provide adequate information indeed. As said above, Google Earth screenshots, accompanied by the appropriate Google Earth placemark, can be processed by TransDEM semi-automatically. TransDEM then can create and place UTM tiles (aka Base Maps) into your Trainz map, right on the spot, with 5 - 10 metres accuracy in the ideal case.

The 32 MPixel limit in TransDEM applies to an individual raster image (topo map or orthophoto) and has to do with TransDEM internal image processing. Google Earth screenshots are the 1 - 2 MPixel region.

For alco_power's project in NSW, TransDEM can download topo map clippings 1:50000 from the NSW WMS server (WMS = Web Mapping Service). There is a detailed tutorial for this server in the TransDEM manual.

geophil

nbrettoner
July 17th, 2007, 10:34 PM
Hi Geophil & Jerker,

My apologies alco_power for perhaps being a bit off-topic on your thread.

Geophil thanks for the info & reassurance that TransDEM will do all that we ask of it.
I've used GE extensively on my section of the DHR Project, applying GE screen-grabs to 1km basemaps.
These basemaps have proven to be invaluable to me, & I look forward to using ones created with the help of TransDEM; for our Narrandera_Tocumwal Project.

:)

geophil
July 18th, 2007, 01:34 AM
These basemaps have proven to be invaluable to me, & I look forward to using ones created with the help of TransDEM; for our Narrandera_Tocumwal Project.


For a project in New South Wales you presumably don't need Google Earth-based UTM tiles (Base Maps) that much. WMS is much quicker. You connect to the NSW WMS server, set up the parameters (all explained in a tutorial), then start downloading map clippings. Once you have sketched the course of the route on an overview map, downloading (and georeferencing) the detailed map-clippings along this route is an automated process. Sit back, have a coffee or a beer and relax.

geophil

nbrettoner
July 18th, 2007, 04:40 AM
For a project in New South Wales you presumably don't need Google Earth-based UTM tiles (Base Maps) that much. WMS is much quicker. You connect to the NSW WMS server, set up the parameters (all explained in a tutorial), then start downloading map clippings. Once you have sketched the course of the route on an overview map, downloading (and georeferencing) the detailed map-clippings along this route is an automated process. Sit back, have a coffee or a beer and relax.

geophil

Hi Geophil,

The WMS data gives the same/better satellite imaging as GE then?.

This all sounds better the more I learn of it!.

:):)

geophil
July 18th, 2007, 05:41 AM
WMS for NSW is based on a vector map data base. Topographic details are dependent on scale. Setting the scale to 1:50000 reveals most details.

If Google Earth covers your project region with 50cm per pixel images you will be better off with GE (scale would be something like 1:5000). But it's a lot of work for a route length of more than a 100 mi. If GE only offers low-res coverage of the area, the 1:50000 topogr. map will be the superior source anyway.

Hence, I would start with WMS, analyse the result and decide later, if and which areas need more detail. Not incorporating WMS would seem like ignoring an easy accessible and valuable data resource.

http://img329.imageshack.us/img329/9165/nswwmssrtmuf9.jpg

The "Zig-Zag" at Lithgow (not all layers activated), as seen through the eyes of WMS, painted on top of SRTM DEM, 1000m UTM grid lines

geophil

nbrettoner
July 18th, 2007, 05:54 AM
Thanks GeoPhil,

We'll follow your valued & generous advice, & as Jerker to do it this way.