Generating terrain from USGS DEM files in SimCity 3000

Contributor/author(s): Marcus Weddle, Joey Hancharik (edited by Wren Weburg)

The following article has not been tested by SC3000.COM for accuracy. This article was submitted by a third party and SC3000.COM can not provide any additional support pertaining to this article.

Here's more specific info on getting a DEM file from USGS to a .bmp:

1. Get the file from the Web site
   http://edcwww.cr.usgs.gov/glis/hyper/guide/1_dgr_demfig/index1m.html (this help is for these maps only--the 7minute ones won't convert using the utility I mention later).

   After choosing which area you want, go to the download page. You are going to click on the compressed version of whichever map you want. But before you click:

   You will probably need to add a GZ mime type to your browser in order to download the compressed file (these directions are for Netscape 4), or you will have problems uncompressing the file. In Netscape 4+, go to edit > preferences, drop down "Navigator" and choose "Applications". Choose "New Type..." and enter:
   Description: Gzip
   Extension: GZ
   MIME: application\x-compressed
   Application to use: -leave blank-
   Uncheck checkbox at bottom
   Hit OK, and then click "Edit" on the new listing (Gzip). Choose the save to disk radio button, and click OK out of the preferences. Now you can click on the link to download the DEM to a directory of your choice.

    

2. Uncompress the file
   Open the file in WinZip or some other uncompressing program that can handle gzip files. It will ask you the name of the file that is contained within--just hit OK. Extract the file to a directory of your choice.

    

3. Convert to a .tga
   Download dem2tga.zip from http://www.alltel.net/~jonl/dem.html. Extract the two files from that zip to the directory you saved the DEM to. Now open up a DOS prompt and navigate to the directory you saved to. Type dem2tga <filefromwebsite> <yourterrain.tga>. <filefromwebsite> will be the file you extracted earlier, and <yourterrain.tga> is the target file. You may have to rename the dem file to something shorter if you are having problems with the 8.3 filenames. There shouldn't be any extension on the dem file unless you put one on and you do need to put the .tga on your terrain output file the program will make.

    

4. Resize/crop tga
   Open the .tga in you graphics editor

   If it won't open (Photoshop 5 won't open the ones I tried), download and install ACDSee (http://www.acdsystems.com/pages/acdsee32.htm) and open the file using this program, then choose edit > copy image. Then go into your graphics program, make an empty 1201x1201 file and paste.

   Now, with great effort, you have the greyscale file, which needs to be resized or cropped to the right size for the map you want to make.

   Joey Hancharik offers this alternate advice for resizing/cropping tga files: I have found that with Paintshop Pro, you can open the .tga file, convert it into a .bmp, and open it in Photoshop 5, if that is your preferred editor.

   See also
   Generating custom terrain from bitmaps
   Real terrain importation Part I: Get & convert terrain
   Real terrain importation Part II: Prepare & import terrain
   Terrain generation with Photoshop 4.0
   Real terrain importation & file edit tips (Macintosh only)
   Real terrain creation supplement
   Realistic space terrain with Unlimited
   Terrain importing utilities and resources
   Notes on scale