Hi Glenn, i have reprojected MyTerrainImage.tif from GCS ( Geographic coordinate system ) to UTM using GlobalMapper successfully, Should i re-project Dted-2 Elevation files to UTM projection as well? İf so; Should i use osgdem command like this;
osgdem --cs "+proj=utm +zone=52" -d MyDteds - MyImage -o... or without --cs and projection info ( since they are already projected) osgdem -d MyDteds - MyImage -o... ??? thx, atilla. Glenn Waldron wrote: > I recommend reprojecting them first. You can use gdalwarp, or a tool like > Global Mapper. > > You may also want to investigate osgEarth as an alternative approach to doing > terrain with OSG. > Glenn Waldron / Pelican Mapping / @glennwaldron > > > On Thu, May 5, 2011 at 1:08 PM, Atilla Selem < ()> wrote: > > > Hi Glenn, > > Thanks for the tip.. but i really need to know, > > > > Where should i do reprojection? In my dted-2 files and/or in my > > GeoTiff.file (since their projections are both Geographic - Lat/Lon) before > > executing osgdem? > > Or should i do re-scaling or whatever after i load terrain in osg > > application? > > And What tool or command option should i use to reproject to UTM? > > > > thanks in advance.. > > > > Atilla. > > > > > > > > Glenn Waldron wrote: > > > > > Atilla,osgdem is creating your model in what's called a "plate carre" > > > projection -- in which degrees are simply reinterpreted as meters. That > > > is why your 2x2 degree cell is appearing as 2x2 meters. > > > > > > > > > You need to reproject into a proper projected spatial reference system > > > (like UTM) to get the correct extents. > > > > > > > > > Check the bottom of this page for tips: > > > > > > > > > > http://www.openscenegraph.org/projects/osg/wiki/Support/UserGuides/osgdem > > > (http://www.openscenegraph.org/projects/osg/wiki/Support/UserGuides/osgdem) > > > > > > (http://www.openscenegraph.org/projects/osg/wiki/Support/UserGuides/osgdem > > > > > > (http://www.openscenegraph.org/projects/osg/wiki/Support/UserGuides/osgdem)) > > > > > > > > > Glenn Waldron / Pelican Mapping / @glennwaldron > > > > > > > > > > > > > > > > > > On Thu, May 5, 2011 at 12:25 PM, Atilla Selem < ()> wrote: > > > > > > > > > > Hi, > > > > > > > > i have tried to generate a terrain (.ive) database using osgdem > > > > commandline options in order to buid a flat database where coordinates > > > > are in meters. After successfull generation i put that terrain in my > > > > osg application and really shocked! Before telling you what i saw as > > > > the output let me tell you my inputs. > > > > - i have four Dted-2 elevation file, > > > > - i have one GeoTiff image which is successfully mapped on dted files. > > > > - Dteds are starting (from 36N, 128E to 38N, 130E). So there are 4 1x1 > > > > degree cells [ Total size is 2x2]. > > > > - GeoTiff image also extends from 36N, 128E to 38N, 130E. So it covers > > > > [2x2] elevation file without no problem. > > > > > > > > Dted and Image Coordinate Systems are: > > > > Geographic ( Latitude / Longitude ) > > > > Datum : WGS84 > > > > Unit : Arc degrees. > > > > > > > > after putting dteds and image in seperate folders ( MyDted, MyImage ) i > > > > executed the following vpb command to generate my flat database. > > > > > > > > - osgdem -t MyDted -d MyImage -l 8 -v 0.1 -o MyTerrain_Flat.ive > > > > > > > > after executig above line and loading Terrain_Flat.ive on my osg > > > > application it was really difficult to find where is MyTerrain_Flat.ive > > > > on my view. > > > > When i zoom in What i saw was a 2x2 meter flat database in osg size. > > > > !!!It was located on x = 128 , y = 36 on my view according to ( 0,0,0) > > > > of my scene!!! > > > > Real size of Dteds of Image was 178 km in Easting and 221 km in > > > > Northing.. i have checked size and everythings was ok with Dted and > > > > Image. > > > > > > > > Now the question is > > > > 1 - Is there a problem with vpb when creating flat database in meters? > > > > 2- Have i missed a command line option? > > > > 3- Why is the generated terrain covers 2x2 meters although it is 178 x > > > > 221 km in real size? > > > > 4- Why it is located in x = 128 , y = 36 ? Those were Lower Left > > > > Lat/Lon coordinates of dteds and image file? > > > > 4- Isn't it possible to generate real size flat terrains in meters in > > > > x,y,z using vpb? > > > > > > > > Any help is really appreciated... > > > > > > > > ... > > > > > > > > Thank you! > > > > > > > > Cheers, > > > > Atilla > > > > > > > > ------------------ > > > > Read this topic online here: > > > > > > > > > > > > > > > > > > > > http://forum.openscenegraph.org/viewtopic.php?p=39045#39045 > > > > (http://forum.openscenegraph.org/viewtopic.php?p=39045#39045) > > > > (http://forum.openscenegraph.org/viewtopic.php?p=39045#39045 > > > > (http://forum.openscenegraph.org/viewtopic.php?p=39045#39045)) > > > > > > > > > > > > > > > > > > > > > > > > _______________________________________________ > > > > osg-users mailing list > > > > () > > > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > > > > > > > (http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org) > > > > > > > > (http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > > > > > > > (http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org)) > > > > > > > > > > > > > > > > > ------------------ > > > Post generated by Mail2Forum > > > > > > > > > ------------------ > > Read this topic online here: > > > > http://forum.openscenegraph.org/viewtopic.php?p=39053#39053 > > (http://forum.openscenegraph.org/viewtopic.php?p=39053#39053) > > > > > > > > > > > > > > _______________________________________________ > > osg-users mailing list > > () > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > (http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org) > > > > > > > > > ------------------ > Post generated by Mail2Forum ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=39090#39090 _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
