|GeHache @ Tue Feb 26, 2013 12:52 am wrote: |
I would like to introduce how I'm getting topo data.
Get 3dem here: http://freegeographytools.com/3dem_setup.exe
It's a program to use SRTM data files that you can get here: http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/
1 file is 1degree*1degree; you can easily find the files you need with their names.
I'm using Google earth to find coordinates of my future maps.
I trace a rule across map horizontally, and respect the length of the side I would like to have (2560m) and trace the same vertically.
I note the exact coordinates of the 4 corners.
I run 3dem and load the hgt files that I downloaded before, using SRTM data option (you can select more than 1 file to load at once).
Then in Operation, I choose F7, I select the zone I would like to fill errors, then enter. Then OK.
Then I choose Operation/F8 to select a smaller zone, then Enter. No matter what selection I made, the program will ask you something more precise where you fill the coordinates you got in Google Earth.
You will have to convert the coordinates in decimal. (deg+min/60+sec/3600)
Then you choose Operation/Change projection, Convert to UTM, WGS84.
In Color Scale/Shaded relief, set Shade depth to zero, and OK.
Then Color Scale, Modify Scale.
Click on the lowest altitude, and select black with Color Controls cursors.
Then select highest in white.
Reselect lowest then Spread To, and select highest, and OK.
In Geo Coordinate, select lat lon Off.
Finally, File/save Map image, choose the extension you would like.
In your graphic program resize to 640*640 and change it to grey scale , save it to png and that's all.
By the way, you can get a screen shot of the exact same portion of google earth and resize it to 4096, and apply it as a texture and you will get it as background either to leave it there as it is or to use it to position object and/or make your trees files.
Hope you enjoy.