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Howto:Create custom terrain

13 bytes added, 18:13, 8 March 2011
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Robot: Cosmetic changes
Your goal for editing area data is to create a shapefile of a seamless layer of polygons which correspond to some type of land cover. This data is then fed into the mapserver and, possibly, TerraGear to create new scenery.
===Evaluating the current data===
Before you begin, please make sure the area you want to improve doesn't already have good coverage. Just because it looks bad in FlightGear does not mean the area has not been improved. For this, you will need to check the Flightgear Mapserver, at [http://mapserver.flightgear.org/ mapserver.flightgear.org].
Let's take a look at the Finistère in Brittany, Western France: if you click [http://mapserver.flightgear.org/map/?lon=-4.41840585539649&lat=48.4484146908477&zoom=11&layers=0B000000FTTFFFFFTFT here], you will quickly see and understand how the Finistère county is known of [[FlightGear]]. Some towns/cities (red), a few forests (green), etc. Overall, it is not a very good resolution: a lot of angles, the detail level is not that good, some towns are missing. If you want a better definition on ground, there is some work to be done! The goal being to obtain something like this:
#[http://mapserver.flightgear.org/map/?lon=13.40385&lat=52.50199&zoom=11&layers=000000BFFFFFFFFFTFFF Berlin]#[http://mapserver.flightgear.org/map/?lon=9.40368&lat=47.63699&zoom=11&layers=B000000FFFFFFFFFTFFF Bodensee surroundings]#[http://mapserver.flightgear.org/map/?lon=-88.55704&lat=43.98436&zoom=11&layers=000000BFFFFFFFFFTFFF Oshkosh surroundings]#[http://mapserver.flightgear.org/map/?lon=-62.87648&lat=17.69865&zoom=10&layers=B000000FFFFFFFFFTFFF Carribs]
You will immediately notice the improvement to the ground. When flying, the difference is huge. Moreover, this enables the autogeneration of cities, trees, farmland, and so on.
# Click ''Map Search''.
# Tick the ETM+ box (left column).
# Click on ''Update Map'' on the right bottom of the map.
# Click on the ''Place'' tab on the upper side of the map, in order to do a search by place, or you can do a search by latitude/longitude.
# In the Place field, type ''Amsterdam, Netherlands'' for instance.
#* A projection box should pop up. Select 'WGS 1984'. After all, that is the globe model used in FlightGear.
# Your vector layer should appear in the left-hand toolbar. You are ready to begin digitizing.
#Select the newly created layer in the layer list, toggle editing (<tt>Layer > Toggle Editing</tt>) and finally select Capture Polygon from the same menu/toolbar.
# With your mouse, left-click on a point at the southwestern edge of the small island.
# We now want to trace the outline of the island. Move your mouse to another point below the first point and click it again. Your mouse should show a red line. The points should not be redundant - for instance, as long as the line between two points is straight, there is no need for another point in between the two.
# Click OK to save the snapping options.
====Distinguishing Land Class Types from LANDSAT data====
You may Google Maps or Yahoo Maps running alongside your program to see what is what on the black/white image, but most areas are recognizable without use of the software. If you need help determining what part of the black-and-white image, please currently refer to the [http://stattosoftware.com/flightgear/tutorial/index.html#distinguishing original Stattosoftware Scenery Tutorial]. Instead of determining in a single band image you can also combine different ETM+ bands in a RGB file. Some information about different band combinations can be found here [http://web.pdx.edu/~emch/ip1/bandcombinations.html].
===Exporting the shapefile===
In order to turn the landclass into scenery we have to split it into seperate shapefiles for each landclass.
If you want to see these shapefiles integrated into the Custom Scenery database you can contact papillon81 and statto (through IRC or Forum). Please be remembered that your data has to be derived from freely available (public domain) sources. Other material can not be integrated due to legal issues.
===Generating scenery===
Please continue with [[TerraGear]] to generate the landclass into useable scenery.
* [http://wiki.osgeo.org/wiki/LandcoverDB_CS_Detail OSGEO Wiki]
===Resources===
* [http://stattosoftware.com/flightgear/tutorial/index.html Tutorial by John Holden]
[[fr:Howto: Utilisé QGIS et images satellites]]
[[Category:Howto|Using QGIS and satellite pictures]]
[[Category:Scenery enhancement|Using QGIS and satellite pictures]]
 
[[fr:Howto: Utilisé QGIS et images satellites]]
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