THIS TUTORIAL HAS BEEN EDITED, TO INCLUDE THE USE OF FantastiCoast. A VBScript THAT WAS USED HAS BEEN REMOVED AND REPLACED BY FantastiCoast.
Hello all!
I've developed a way to get real world data from Google Earth (actually the data is provided by CGIAR-CSI and appears on Google Earth with the use of a kmz plugin) and create a map.
It involves the use of FantastiCoast, an application I've made, that creates an image file to use in SC4Terraformer or SC4Mapper or SC4 itself (not recommended).
The results are quite good. Check out a screenshot from the greater Athens area, just as it came out from my process and not terraformed at all!
Software you will need:
Google Earth
The SRTM Digital Elevation Data from srtm.csi.cgiar.org There is a download link in that page, named "Google Link" that downloads a file named srtm41.kmz
FantastiCoast, attached at the end of this post
SC4Terraformer or SC4Mapper
SimCity 4
Steps to make your map:
1. Open Google Earth by booting SRTM Data
After you download srtm41.kmz (41 means version 4.1, it will probably be updated sometime...), save it in a folder and double click it. It will open Google Earth, with SRTM data loaded.
Enable the place in the sidebar
and you will see the results on the map
2. Locate the area you want and download the data you need
I will use the area of Athens that you see in the beginning of this tutorial.
So, click on the green icon of the tile you are interested in. If you need data from more tiles, read further.
Then, click on the link
and watch the results
Next, enable the Data checkbox in the sidebar, inside elevation preview --> Global legend
and you will see the links for the data of the subtiles enabled
By clicking on the square icon next to the the "Data" label, you can download the precious data!
It is an .asc file.
For my example, I used the data from 4 subtiles, because the area I wanted was in the middle of them.
So, I downloaded
srtm_41_05_4_3.asc, srtm_41_05_4_4.asc, srtm_41_05_5_3.asc and srtm_41_05_5_4.asc
*** As I mentioned earlier, if you need data from subtiles of 2 different tiles, go get them! Now you know how.
You can now close Google Earth.
There is one extra optional step which is not covered by this tutorial: Using DEM data in a GIS application (ie Global Mapper) to get a correct scale. Look at the end of this post for further details.
3. Use FantastiCoast to create the bitmaps
Go to the end of this post, download and install FantastiCoast. * You need Microsoft's .NET Framework 4 to run FantastiCoast
...
You can read usage instruction for FantastiCoast here
In short, open the .asc file and click "Launch". Then save the file as bmp or png or 16bit png. It is ready for SC4Terraformer or SC4Mapper!
If you downloaded more than one file, repeat for the rest.
You can see a downsized sample (originals are 4,11MB, 1200x1200 pixels):
*** Do not forget: SC4Terraformer and SC4Mapper, just like SC4, need bitmaps of a specific size (64 pixels per km + 1 pixel, ie 1025x1025 for 16x16 km). You will get better results if you crop and stitch them instead of resizing them before using them in SC4T/SC4M/SC4. Do not let SC4T/SC4M resize the picture because the terrain will look very spikey.
Ok, I guess experienced map makers know what to do next...
However, I continue the tutorial, just in case you need more help.
4. [optional] Stitch the bitmaps, in case you need data from more than one
Using a picture editor, you can stitch the pictures made by the script. For those who wonder, NO, they are not distorted, you can stitch them just by placing them one next to another.
Here is an example of a 2400x2400 picture
5. Crop the final picture
Now we have a bigger picture which contains the area we wanted. After we stitch the pictures, we have to crop the final picture to the size we need (1025x1025 pixels is the standard for a 16x16 map). The rule is
64 pixels * mapsize + 1
so for a mapsize of 16x16 km we need a 1025x1025 picture and for a mapsize of 16x32 we need a 1025x2049 etc.
Of course you can also resize instead of cropping but remember: Resizing always results in some kind of distortion, so you would better avoid it as much as possible. If you have to do it, do it only once and remember that you will probably have to Equalize the map in SC4T, in order to reduce some spikes you will get from the distortion.
So, after cropping my final picture to a 1025x1025 bitmap (I don't thing you need a screenshot for this), I am ready to go with SC4T.
6. Use SC4Terraformer or SC4Mapper
I have only used SC4T because I have some installation problem with SC4M. However, there is no big difference.
Open SC4T, choose a Region you have created in the game for your new map, and click "Import image" under "Global tools". Pick your final image, click OK and them RGB and... voila! You have your new map, ready to play!
...well, almost!
Sometimes you might need to use "Equalize" just once, because the map will look a bit spikey. Judge by your own.
After saving, you can open the tiles one by one in the game (DO NOT USE RECONCILE!) and "save and exit to region", to render the map correctly.
7. Some finishing you have to do
The satellite data does not distinguish water masses such as rivers and lakes. You will have to create them on your own. Usually, they are visible as flat areas (lakes) and banks (rivers).
--- The scaling problem ---
- SRTM Digital Elevation Data has 90m precision. It is not bad, but it is much less data than the supposed size of the maps you create. Actually, your final map is downscaled by 16:90, meaning it is about 5 times shrinked. In my map, an area of approx 90x90 km, was turned into a map of 16x16.
There are solutions, one of which is approached by MallowTheCloud in his "Making Accurate-Scale Real-World Maps" tutorial. I will try to write a complete tutorial on the whole process soon.
Another solution of course, would be to resize the picture, regardless of the reduced precision. Try it, it might not be too bad...
I hope you find this tutorial useful and you enjoy your new maps!
xentrix
PS: I'd love to see some screenshots of any map you might create by this method, especially if you find anything weird with FantastiCoast. Thanks in advance!
FantastiCoast v1.0.0 setup.exe.zip