Tutorial: Importing Detailed Terrain from Google Earth

[D-Hunter]

This tutorial will show you how to extract heightmaps from locations on Google Earth and then import them into Unreal Ed for use in a level. Here's what you'll need:

-Google Earth (of course) - http://earth.google.com/
-This plugin for Google Earth.
-MicroDEM Map Tool - http://www.usna.edu/Users/oceano/pgu...odem_setup.exe
-DGUnreal's HMCS - http://www.lilchips.com/dgunreal/tools-hmcs.asp
-GIMP (free) or photo-editing program BESIDES MS PAINT that can save as TGA

Once you've download everthing from above and installed MicroDEM, double click the Google Earth plugin file. Google Earth will load up with a grid over the entire earth. Search for the grid square where your terrain is located. For purposes of this tutorial, I'm going to use the Grand Canyon.

The Grand Canyon is located in srtm_14_05. Click on the green mountain icon and scroll down to the list of servers. Under UK or US servers, choose "Download the DATA tile in zipped ARCASCII format" from either FTP or HTTP (note: downloads are usually very slow and the file is about 50MB, so try all 4 links to see if you get a faster connection). Once you have the file, unzip the ASC file to your desktop. Fire up MicroDEM (close the info window) and go to File>Open>Open DEM, under Files of type select ASCII Arc Grid and navigate to and select your ASC file. You should see something like this:

Click the 6th button in the small window 'Subset & zoom' and select the region you would like to include in the heightmap (you may have to do this multiple times, but don't worry, there's an 'Undo subset' button right next to it). For the largest map, you want a 2x2 grid area from the initial view (the max you want to go is 10km by 10km). Now right-click on the map and select 'Grid' and set the Grid option to 'Neither' and click Ok. Next, right-click and select Legends/marginalia and uncheck the four boxes on the right, click Redraw map, then click Ok. Next, right-click, select Display parameter and click Elevation. Set Display colors to 'Gray scale' and click ok. You should now have a grayscale image with no grids and no boxes (except green arrows at the edges). We're not done yet: the map needs to be 513x513 or smaller. If it looks larger than that (more than half the height of your screen if you're running at 1280x1024), click the Zoom out button (magnifying glass with a minus in it) and click Ok. Finally, right-click the image and click Save image and save it as a BMP file. Now, HMCS doesn't seem to properly support this type of BMP file, so open it up in GIMP or another photo-editing program and re-save it as a TGA file without RLE compression. Fire up HMCS, make sure that in the Options under Scale function the 'Scale all map files' box is checked, click open, set the File type to 'tga - Targa...' and open your file. Then click File>Save as (click yes on the 'power of two' alert) and save it as File type 'bmp - Unreal G16 Heightmap' with a unique name. You now have a working Unreal 16-bit grayscale heightmap. Start Unreal Editor, create the default cube brush, move it down as far as you can without leaving the editor box, and add it. In the Actor browser, select Terrain (under Info), then right-click on the top of your cube and click 'Add Terrain here'. Then in the Terrain editor window, check the boxes 'Heightmap only' and 'Into current' and click import. Select your G16 heightmap and click ok. You should now have a terrain in the editor, but it doesn't look the way it should. First, if you see walls at the edges of your terrain, lower the NumPatches slightly in the directions it occurs. You will have to play with the DrawScale and set DrawScaleZ to about 1/4 of X and Y for your terrain to look proper (if your heightmap is 10km by 10km, increase the DrawScale by factors of 1.0 and move the terrain until it touches the edges of the limiting box on the X and Y axis). Remember to move your terrain so it is back on the grid and centered in the editor box (even if it's bigger than the grid). Your terrain will look extremely jagged due to the limited NumPatches, so select the smooth tool and set its strength to 50 and its radius to 100000 and quickly smooth over everything. At this point your terrain should be detailed, smooth and ready to use in a level. That's all I could muster for this tutorial at the moment, post any questions/comments below.

[apoisonedgift]

Nice tutorial

[nomadicus]

Geez. I have got to try this this weekend. Nice one!

[heyqule]

hope we'll to see large maps based on our earth lol...

[D-Hunter]

Sorry it's all in boring paragraph format; until I can revise it a little, read carefully as there's a lot of important steps buried in there that are required for it to work properly.

[Doublezer0]

if you were to do this to an area larger than you would want to use for an unreal map is it possible to split the file into equal sections for streaming?

[D-Hunter]

if you were to do this to an area larger than you would want to use for an unreal map is it possible to split the file into equal sections for streaming?

Someone else mentioned that you were still limited to the size of a level, so I think the box is the limit (defined in native coding). A TC mod could possibly scale down all objects and players with a few clipping issues, meaning almost limitless maps.

[Denny]

Trust me, making a terrain that covers the whole work area is so damn big that you can't properly fill it alone with quality. Unless you're satisfied with just a terrain, with no props, and a bunch of vehicles. It takes a hefty amount to traverse from one end to the other.

[D-Hunter]

Trust me, making a terrain that covers the whole work area is so damn big that you can't properly fill it alone with quality. Unless you're satisfied with just a terrain, with no props, and a bunch of vehicles. It takes a hefty amount to traverse from one end to the other.

Have you seen the Mt. Everest map being worked on?

[TheRalfZer0]

Hey man, thanks once more, I have table mountain!!! Woot!!!

http://www.tablemountain.net/

[nomadicus]

I am using MicroDem 10.0 build 2008.1.23.1, I downloaded two strm files I was interested in and when I load either one I get an access violation error. Any thoughts?

Solution:
There is a bug in this version of MicroDEM. If you go to their ftp site, one can download a later, abeit debug, version of the .exe.

[Cosmix]

Have you seen the Mt. Everest map being worked on?

Ya, I've seen MountEverest Map announcement! Nice tutorial and interesting idea

[Brits__Hit]

I knew I had the right idea when I downloaded Google Earth to get some terrain maps.

Nice tut.

[D-Hunter]

I am using MicroDem 10.0 build 2008.1.23.1, I downloaded two strm files I was interested in and when I load either one I get an access violation error. Any thoughts?

Solution:
There is a bug in this version of MicroDEM. If you go to their ftp site, one can download a later, abeit debug, version of the .exe.

What type of file are you trying to load? You should be loading an ASC file.

[nomadicus]

To avoid back to back posts, I found the solution and posted it in my original post. Just know that version build 2008.1.23.1 has a documented bug in it and can't read the .ASC files. Downloading MircoDEM.exe from the FTP site fixes it (was built earlier this month).

And a big thank you for this tutorial. Very nice.

I would suggest adding one thing: If you want to smooth the entire terrain before doing the import, download G16ed.exe and use the smooth function. http://homepage.ntlworld.com/martingbell/ut2003/

[DeineLtan]

Hi guys! Anyone of you still active?^^

Big props for that idea. If that really works, that'd be just what I need.
I'm planning to make simplyfied real world cities for my own UDK project.

Unfortunately, the tool MicroDEM seems to be totally buggy.
If anyone made it work and is still here, please give me a sign...

regards

[Captain Nicirus]

Good tutorial but every time i open it instead of giving me the srtm coordinates it gives me lattitude and longitudde how do i change that i downloaded everything but it wont work plzzzzzz respond soon im running out of time to make this.