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marlo.steed
11-11-2005, 10:29 AM
I am trying to get some Canadian elevation data (files.dem) into a terrain in Lightwave. I have gone to the elevation Lightwave Tutorial numerous times:

http://www.newtek.com/products/lightwave/tutorials/surface/texturing/texturing_landscape.html

Unfortunately the tutorial doesn't seem to work for me. I know this has been asked before. I did a search and found a couple of threads but none seemed to help.

One suggested a plugin at:

http://amber.rc.arizona.edu/lw/elevations.html

I have loaded that plugin but it doesn't seem to appear in the menus. It is listed in the plugin files. Does it automatically get activated? Regardless it doesn't seem to work, I try loading the dem files as an image and nothing happens.

Is this one of those features that used to work but has been disabled by updates? (currently using 8.5)

Darth Mole
11-11-2005, 11:43 AM
You might need to manually add it to one of your menus so you can get access to it.

marlo.steed
11-13-2005, 04:36 PM
I have scanned the plugins and it doesn't appear anywhere - looked for it in additional items. Usually when you scan new plugins that is where they appear.

Update: Lightwave does show the plugins as being loaded in the image i/o group but those still don't show up in the Utilities:additional listing. It still does not import dem files.

I sense the pugins are suppose to work transparently when you load an image but perhaps they don't support dem files. Maybe I need to translate those files to another format.

Has anyone had success with this?

Suggestions?

marvinl
11-15-2005, 11:03 AM
The problem is that the .dem file extension really doesn't describe a particular type of format. There are many types of Digital Elevation Model formats, and unfortunately no common standard for naming them with unique file name extensions (like there are with image file formats). So .dem could really mean any one of many actual formats (SDTS, GTOPO30, SRTM, USGS ascii, MicroDEM, ...)

Do you know any more about the files you are trying to read other than the fact they have a .dem extension? Is there a web page that describes the files? I'd be happy to help, but just knowing they are .dem files is not enough information to know whather any of the Lightwave plugins can actually read the data.

marlo.steed
11-15-2005, 02:18 PM
marvinl,

Thanks for the offer. It would be great if I can get this working.

The site call them CDED files but they have .dem extension. There is actually a pdf that describes the file format but it is greek to me

http://www.geobase.ca/doc/specs/pdf/GeoBase_product_specs_CDED1_v2_1.pdf

Here is the link to the site:

http://www.geobase.ca/geobase/en/

The other day when I accessed this site I was able to download without signing on but now it seems that you will need to sign on ...but it is free access once you create a login
I was able to attach one of the dem files here.

Let me know how it goes.

marvinl
11-15-2005, 03:07 PM
The files on that site are USGS ASCII dem files. Unfortunately, none of the LW image loader plugins (SDTS, ElevationModels, or MDEM2) will load that format. On a PC, I was able to use MicroDEM (http://www.usna.edu/Users/oceano/pguth/website/microdem.htm) to load the file and then save out a MicroDEM2 file, which can be loaded into LW with my MDEM2 plugin (http://amber.rc.arizona.edu/lw/mdem2.html). But MicroDEM does not run on a Mac, and I don't have a Mac version of the MDEM2 plugin. So if you want to do this with other dem files from that site, you are probably out of luck on a Mac. But for the file you attached, I was able to save it as a .hdr file once I got it into LW. With that format you should be able to load it into Mac LW and still give you all the accuracy found in the original dem file.

ackees
11-16-2005, 03:46 AM
There is a free app called 'SimpleDemViewer' from the apple download site that lets you clearly see your .dem file, it has no export functions though.
There is also a Unix app that uses the X11 interface on the Mac that looks very pro, also free, but I cannot remember the name just now.
Wait...
The brain cells are waking up...
It's called Grass Gis
http://grass.itc.it/
Not sure where the US site is.
Let us know if you have success with this, I have been meaning to play with it but not had the time yet.
It does look good.

marlo.steed
11-16-2005, 03:50 PM
I want to avoid the hassle of another intermediary app, particularly if it involves install of X11. Never used that before. I guess I will figure it out if Lightwave doesn't work.

Marvinl,

Thanks for the infomation. Unfortunately, that one file is just the tip of the iceberg. I may want to convert a whole lot of files and wouldn't want to impose on anyone to convert them all. Perhaps I will need access to a PC and Microdem.

Thanks for your time on this one.

marlo.steed
11-16-2005, 10:40 PM
Oh, here is a quick render of that terrain.

Sidebar: now the fog works but if I go back to another scene - the fog doesn't work - very frustrating (as far as I can tell with the same settings).

marlo.steed
11-17-2005, 12:29 PM
Bottom Line:

To summarize then, dem files don't load into Lightwave, so you need some other program to convert the files into something Lightwave can handle. Unfortunately there are no programs that do that in OSX. You either need to use Grass in X11 or MicroDEM on Windows.

Nigel Baker
11-17-2005, 02:34 PM
Hello Marlo,

This has always been of interest to me.
I was always curious of how to get these files int the Mac.
Like yourself tried the original tutorial ages ago and got frustrated.
Thanks for all the hard work.
I am going to download the Grass and SimpleDem Viwer just for the H e l l of it all.

Thanks again and I hope that this developes into something along the way.

marlo.steed
11-18-2005, 10:21 AM
Nigel,

I just tried installing X11 and Grass. However, when I go to import from Grass I get an error messages. It seems that there are two DEM formats - tried both with no succes. Can't figure it out. I will try again today but if you get it to work, let me know. I also tried TNT (check out Apple download pages), which looks like it should import that format as well - same problem.

Nigel Baker
11-18-2005, 11:35 AM
Hello Marlo,

Yes I downloaded Grass and then stumbled with X11.
I have to dig out my G5 DVD's to look for it.
Will keep and eye to this thread and will post back with any changes or sucess stories.

Thanks again.

marlo.steed
11-23-2005, 01:49 PM
Nigel,

Any success with either Grass or TNT? I couldn't get either to import the DEM data. ...unless I am doing something wrong.

Nigel Baker
11-23-2005, 04:21 PM
Hello Marlo,

Very sorry, I have been up to my eyes with family problems (health wise).
Tomorrow I intend to get back to work, work.
Somewhere then in there I hope to sneak some time in to look at the X11 and the Grass issue.

Regards.

marlo.steed
11-29-2005, 03:57 PM
Success at last! Perseverance pays off.

Okay, here is how to get dem files into Lightwave (at least the Canadian files).

1. download Landserf
http://www.soi.city.ac.uk/~jwo/landserf/

2. open your dem files using the file format - USGS Native DEM (.dem) - this may not work for other formats

3. this produces a color image of the height map (see image below) - don't use this as your height map, because the colours will mess up the height. However, if you want this saved as a png file - use the Save command from the File menu (select the appropriate file format and make sure you use the png extension - I had problems with the other formats.

4. go down Edit menu and select "edit raster"

5. Go to colours and select Edit.

6. use the "Preset colour" menu to select the gray scale gradient setting (black to white) - note: the presets don't show up till I start to scroll.

7. That should set it to a gray scale height map.

8. use the Save command from the File menu (select the appropriate file format and make sure you use the png extension - I had problems with the other formats.

That should provide you with a terrain height map you can use with the terrain deformation in the object's properties panel of Layout. I had to set the texture amplitude to 600 in the texture editor. Also crank up the geometry subpatch level. I used a simple plane divided into 20x20 polys as the terrain object with subdivisions turned on.

3dworks
11-30-2005, 12:03 PM
did you ever try landserf? maybe it solves your problem.

http://www.soi.city.ac.uk/~jwo/landserf/

it's a great free osx java application and i supports lots of file formats:

http://www.soi.city.ac.uk/~jwo/landserf/landserf220/doc/howto/fileformats.html

hope it helps...

markus

Nigel Baker
12-02-2005, 04:47 AM
Hi there

I just realised that Vue 5 say that they can handle these files.
So if you have upgraded to Lightwave 9 you could bring them into Vue and then export too LW.
So this may be the best and quickest way round.
I have Vue but have not tried this yet.
I find it hard to look at Vue, can't climitise to it yet.

I will force a test soon,

Regards.