Tutorial: Converting a DEM to a heightmap

[TrickyVein]

Well, your heightmap is only as good as it looks in the end, no matter how you're importing it. Figuring out what a good heightmap looks like takes some practice, but I don't reckon you'd find a program much speedier than tesanwynn for importing heightmaps on the fly.

[Fistandilius]

Well, your heightmap is only as good as it looks in the end, no matter how you're importing it. Figuring out what a good heightmap looks like takes some practice, but I don't reckon you'd find a program much speedier than tesanwynn for importing heightmaps on the fly.

 

I think my knowledge of heightmaps is what's holding me back. I didn't really understand what you said about.... quads was it? I was hoping I would pick up on it as I went through your tutorial. But I actually tried to extract a heightmap from Oblivion and try to put it into Skyrim to see if I could figure it out and I couldn't even manage that, so clearly it's my knowledge of heightmaps and the proper settings that's holding me back.

[TrickyVein]

I may not have provided a direct link to this specific page, but here you go.

[unimportanthero]

Resurrection!


So, going to the USGS site, none of the files I have downloaded have included a DEM file. For reference, I am looking at Lincoln County, Nevada. I have tried the 'Draw and Download by Bounding Box' option and the 'Download by Coordinate Input' option to no avail. All the files are that come in the zip are incompatible with the VTP application and are not in its list of elevation file formats, despite the fact that I am downloading 'elevation' files from the USGS site.

 

Is there something I am missing?

NED 1 arc second download tool

Is this not available now or something? Because the link leads to the USGS TNM 2.0 Viewer - which does allow downloading but is not sending usable elevation data, at least not for the VTP application. Any thoughts?

Thank you very much.

:)

[TrickyVein]

They updated it.

 

And now I have to rewrite the tutorial.

[unimportanthero]

Alas.

Edited to Add: I did find a site that has DEM files for specific areas in the United States. Here is the link.

http://data.geocomm.com/dem/

Here is the page where I found the area I am interested in making a mod for - although the files only cover small and specific areas. They still work though, with every part of the tutorial except the USGS website bit. You just need to know what name GeoComm gave the areas you are looking for and then import them individually, but the VTP program will arrange them together in the right place. Once it does that, then they can be exported as a heightmap BMP file. Each DEM file is downloaded as a TAR.GZ archive that needs to be unpacked first with 7ZIP but the VTP program can totally read the unpacked TAR file. So maybe this will be helpful to your rewrite efforts.

Edited to Add Again:

So yeah. Getting all the individual layers to become one layer requires 'Sample Elevation' under 'Area Tools' with 'Create New Layer' selected. Also, the file will need to be flipped vertically as, for some reason, VTP flips it around when it exports.

Edited July 30, 2014 by unimportanthero

[Fistandilius]

Still having trouble with step 3.... I managed to get access to photoshop (CS5, 64-bit)

 

Select your region of interest, bearing in mind that quads within the GECK (named according to this map) are 1024x1024 pixels across at 72 pixel resolution.

 

 

That part is mostly clear, but I just want to point out that later in your instruction you say that the file should be 2MB and anything bigger will crash the GECK. Which means you should probably just ask us to use a 1024x1024 area if this is the case. I've read elsewhere that the GECK is supposed to handle up to 4096x4096, which is larger than 2MB. So some clarity here?

 

Also, in regards to selecting my region of interest, what is your method for doing this?

 

What I did was create a new image 1024x1024 (16-bit, grayscale), paste the entire map over it, move the map until the area I want is in the background view, and then merge down. Maybe this is incorrect.

 

Go to "Image," "Adjustments," and select "Gradient Map." Make sure 'dithering' is enabled (either in the dialogue box or properties). This will apply the selected gradient over the entire range of values within your image resulting in a smoother, superior heightmap. *IMPORTANT* Choose appropriate colors for your lowest and highest values for your gradient map in the color boxes on the toolbar. I find that a total range of values between 10% and 35% gray (25 brightness values range) yields close to satisfactory results once you import into the GECK. Higher values = probably higher than Jacobstown, and lower = definitely underwater. This process might need to be repeated with different values to your liking and depending on the absolute values of your elevation in your DEM.

 

I _think_ I did this step right. I selected adjustments, gradient map, checked the box that said dithering and then clicked on the colored image to bring up a menu with more options. Here I saw two "sliders" and set the top and bottom of each slider at 10 and 35, respectively, and then set the small diamond at 25. The results seemed very dark to me, but I don't really know much about what a proper heightmap should look like.

 

*IMPORTANT* Export your correctly sized images in this format, exactly: 16-bit, grayscale, RAW, non-interleaved, IBM bit order. If everything is formatted correctly they will be 2 MB each. Anything else will likely crash the GECK. Name them according to the map above. The Mojave Wasteland does not cover a playable area in excess of four quads (I think...anything more just seems waaaaay too big, and who would want to spend time working on something that large anyway?)

 

When I choose "export", the only option available is "Paths to Illustrator" which I assume imports the image into Adobe Illustrator. export Data Sets as File is grayed out. When I choose "Save as", I am given an option for Photoshop Raw... Is this the same as a normal .RAW file? I have the option to choose IBM PC, but I don't have an option of non-interleaved.

 

Also, what exactly do you mean by "name them according to the map above" The map shows cell coordinates, but that doesn't give me a clear idea of the format you want me to use.

 

Lastly, when I create a new worldspace and try to import my heightmap, the GECK can't find it unless I put it in the HeightField folder of the Data directory, in which case it will instantly crash the GECK.

 

So... I could use some help here. If you can give me some suggestions. I can post screen shots if you want, or my height map file.

 

Also curious why you brought back the CS2 link. It still clearly states it's for people who previously owned the software, and it's not just free software.

Edited July 4, 2015 by Fistandilius

[Fistandilius]

Ok, I stumbled upon the correct filename format in the page you linked to on the GECK page. So that corrected the crash to desktop and allowed me to load the heightmap in the GECK, but when I did this was the result, so I guess I did something else wrong.

 

 

[Fistandilius]

Anyone please?

[Roycesraphim]

Are there any other good tutorial sources besides this one?