T3D2 and texture mapping over a terrain

 


How to apply bitmap data onto DEM data


Texture at present only works for square terrain data.
Your stripe count when creating the terrain has tbe equal. Like 10 by 10 .

Use some tool , like Snagit, that allows you to screen grab an area from a scanned map.
The area has be also square and the pixel count must be power of 2.
Like 256, or 512 or 1024 ...  Correction, also 500 by 500 works.

Save the jpeg or gif in the SITES/sitename/IMAGES directory
In the code
Select the site
Press the Map Processing Button
select the scanned map file
use the < or > buttons to stretch the pixel image over the terrain
The value in the middle, is the amount of stretch, make it smaller to move the map less
Once you are happy with what you see, you can Save your work
And , if you want, make this map your default for next time when you load the site.


Where to find  Bitmapdata

Possible sites from where to get bitmap data is

Terraserver Data from  http://www.terraserver.com

 MRSID https://zulu.ssc.nasa.gov/mrsid

How to use Terraserver Data

    1. in your GPS , Mark, Enter your take-off as a waypoint.
    2. Get the coords of your take-off by setting the format to dd.dddddd
    3. Using Decimal degrees, write the take off point down .
    4.  in T3D2 create your flying site, using those take-off coordinates and use 15 by 15 stripes
    5. Go to http://www.terraserver.com, find your site
    6. Move the cursor , with the Pan option active, until it shows the same coordinates that you wrote down
    7.  The picture now gets recalculated with your take-off in the center
    8.  Use a screen grab utility, like Snagit, and copy the region of the map on your screen as a 500 by 500 pixel image.
    9.  Save your images as a gif file in the IMAGES directory of your flying site
    10.  In T3D2 use the MAP PROCESSING and select the gif file that you just created
    11.  You  end up with  a  map which is a very close match over the terrain

     


     

    MRSID Data

    https://zulu.ssc.nasa.gov/mrsid

    Activate the Select Image Radio button
    Choose your area
    In the new window, click on the download button
    Then ftp the tar file to a UNIX box, tar -xvf it, get the data back to your PC