DEM data question

[Austcoop]

Hi all,

not sure if this requires a new thread, but I'll start one anyway! I've downloaded the DEM data I require for a route project from this site http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/Eurasia/. There is no issue with downloading and getting the terrain to form on pressing 'T'. However, I do have a question that I am a bit stumped to solve.

I have all the required route decals (created using RWdecal) and I have downloaded the DEM date for the area I need. How do I synch the two together? I created my blueprint using RW tools, making sure that the Lat and Long numbers were correct for the area I want. However, when I press 'T', it creates a tile of terrain that isn't in relation to the Lat and Long numbers or the decal. Is there a quick fix so that when I press 'T' it creates the correct terrain tile so I can lay the decal straight onto the terrain?

Thanks in advance, James

[class43HS125]

hi,
First question would be, which part of the world are we talking about.
Second question, Have you checked that you have the lat and Long numbers the right way around in all places.
The correct lat/long numbers but put in the wrong places in the route blueprint, down loaded dem data. - sign missing for south or west is a possibility.

There is no ingame/software trick that gives you connection between the terrain/dem and the RwDecals, you have to place the decals just like a scenery item. The reality is that just like a scenery item you can place any Rwdecal anywhere in the world if you so desire

Ross
NZ

[Austcoop]

Hi Ross,

thanks for the reply. I am trying to create the route from Buxton to Peak Forest and Buxton to Dowlow, in the UK Peak District. Using Google Earth, I located the co-ordinates of Buxton station (53 degrees 15'54.10 N and 1 degree 55'10.38W) and then compared them to what was in the download list at http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/Eurasia/. The closest .hgt file was N53 W002, so I downloaded this. The next available file was N54 W002 so, for good measure, I also downloaded this. I took the liberty of finding a .hgt file viewer so I could see exactly what i had downloaded. The second file, N54 W002 covers an area measuring 75 miles x 70 miles x 45 miles!!!!!!!!!!!! The first file is even bigger, as it doesn't have a coastline. The route I want to create is only about 10 miles long! So, you can see my sticking point. I have a DEM file that covers a huge area and I don't know where the start point for my route is. Is there any logic to the tile laying when i press 'T'? Ie, if i enter the correct co-ordinates for Buxton (as above) and press 'T', should RW automatically create the terrain tile for those co-ordinates or not? Or does it create them starting from the top left of the terrain area, top right, centre or what? I'm totally confused!!

James

[class43HS125]

Hi,
First off, yes the hgt files can be "huge". in reality they are one degree in both directions which is the sort of distances you mention. Not a problem. RW will only use the information it requires for the 9 tiles centred on where your cursor is when you press the T key. A tile is 1 kilometre square I think.
Using the decimal degrees option in Google earth you will get the lat. and long. numbers that you need to see in the compass fly out of RW to get the correct terrain at that location. The route only being 10 miles long is not an issue at all. The route starting point in your route blueprint is significant though as this is what decides where your route really is in the world. This is a common placed where lat. and long. get mixed up.
The starting point of your route is the lat. long. that you have put in your route blueprint in decimal degrees. It can be anywhere you like. I would suggest that in your case the station lat./ long. is a good choice.
A good tip is to down load the hgt files one out in all directions from the one you think you need. The logic being that one can never remember which direction the hgt file covers from its starting point. RW will only use the dem data it needs.

info only....So long as you have the relavant hgt file in the RW .....\DEM\SRTM folder for the lat long shown in the RW compass flyout then RW will add the 9 tiles of terrain around your cursor regardless of your routes starting point .

Ross
NZ

[Austcoop]

Hi Ross,

Thanks for the comprehensive reply. I'm much clearer on this now. Thanks again for your time, I'll let you know how I get on.

James

[Austcoop]

Arrgh!!! This *%$£@~! DEM date is driving me crackers! Having read and understood Ross's reply, I deleted my old route blueprint, cleared the file, created another one with RW tools and now I can't get the DEM to appear when i press 'T'. The .hgt files are present in the DEM/SRTM file, the co-ordinates are correct on the RW compass fly out tool, the blue print is correct, but despite me hammering the keyboard to a pulp, the terrain won't load! Any ideas anyone?

James

[hertsbob]

Hi

Just wondering whether you've made sure you've got the Object Tools selected before you're pressing T?

Cheers

Bob

[antonyperks]

And make sure you select your folder name on the right hand fly out under the providers?

Youll get it I did ........................havent been able to do it again though..................

[Austcoop]

Hi,

Yes, as suggested I have the object tools selected and I've also ticked my folder name under the providers section. Still nothing. The file path (appears) correct, Steam\Railworks\DEM\SRTM and the .hgt file is in the latter file, but still nothing!? It's really driving me mad now. I've deleted and reloaded my Source file about 5 times, reloaded the blueprints, basically started from scratch, but despite all that, the terrain data is resolutely refusing to play ball.

Confused and not a little p****d off now!

James

[gypbrc]

Can I suggest you try downloading N53 W001 and N54 W001 into the same path.

[Austcoop]

Can I suggest you try downloading N53 W001 and N54 W001 into the same path.

Hi, done as you suggested, no different. I really am at a loss now. I had the DEM data working fine, but (stupidly) deleted the route to start afresh. I haven't done anything different in the set up of the blueprint, or where I have extracted the .hgt files to. I'm on the verge of smashing this computer to pieces now!

James


Ps, here I just loaded the blueprint with RW tools to check it. If anyone can spot something I've done wrong PLEASE tell me!!!

[alanch]

Latitude 53.1540, Longitude -1.5443 I think - unless you are modelling in the Indian Ocean north of the Seychelles.

[Austcoop]

Alan,

Your a genius! I've been putting the lat and long numbers the wrong way round all the bl**dy time!!

Thanks very much, you've saved my sanity!!

James

[alanch]

Alan,

Your a genius! I've been putting the lat and long numbers the wrong way round all the bl**dy time!!

Thanks very much, you've saved my sanity!!

James

No problem - I did a quick check on Google, as I thought you had them the wrong way round. From what I remember, you haven't been the first to do this in Railworks.

[class43HS125]

hi,
.....
Second question, Have you checked that you have the lat and Long numbers the right way around in all places.
......
Ross
NZ

A very common mistake