Hi Renzil, Are you asking how you could tile the geospatial files into different levels of detail and also keep them in an image base format? Take a look at GDAL2Tiles for some potential inspiration: http://www.klokan.cz/projects/gdal2tiles/
In addition, you could consider just referencing the original source file and passing in the options to only load a clipped out region at a given resolution using the ReaderWriterOptions in the GDAL plugin. Thanks! Jason On Thu, May 22, 2008 at 5:50 AM, renzil d'souza <[EMAIL PROTECTED]> wrote: > > Hi > > I'm writing a plug-in that is able to generate terrain on the fly on the > GPU, which works with the paged-LOD system provided by osg. For it to work, > I need my DEMs in their original raster formats (like tif), and I also need > my DEMs to be 'subtiled' similar to how the textures are currently subtiled. > My DEM geometry/terrain-tile data is no longer generated through osgdem but > is instead generated on the fly from these subtiles (depending on distance > from viewpoint). I need various resolutions of the DEM data in order to do > this. My idea was that, since the DEMs are also images with a single color > value per pixel (representing height), I could pass these DEMs as textures > with the -t option and it would output a set of dds files which contain my > DEM data at various resolutions. The co-ordinate system info and any other > transformations to be applied on these dds files I would store in my scene > graph which I output to the filesystem, but I wouldn't store the geometry > itself. > > When I try to do "osgdem -t " it is giving me a set of dds subtiles, but > when viewing them in osgviewer they are totally white, which means none of > the height data is stored in these dds files. How can I achieve this ? > > Again, thanks for your time. > > Renzil > > > Date: Thu, 22 May 2008 09:00:08 +0100 > > From: "Robert Osfield" > > Subject: Re: [osg-users] How to subtile DEMs ? > > To: "OpenSceneGraph Users" > > Message-ID: > > > > Content-Type: text/plain; charset=ISO-8859-1 > > > > Hi Renzil, > > > > I don't really understand what you mean. The database built by osgdem > > doesn't contain any DEMs, it's either just polygonal based or using > > osgTerrain::TerrainTile if you use the --terrain option. osgdem > > builds the geometry data based on the DEMs it loads, but once the > > geometry is created the DEM data is just deallocated as there is no > > further use for it. > > > > Robert. > > > > On Wed, May 21, 2008 at 11:13 PM, renzil d'souza wrote: > >> > >> Hi > >> > >> Currently osgdem (vpb-0.9.7) in paged-LOD mode generates various > subtiles for textures which can be output as dds files. I need to subtile my > DEM data in the same way as dds files, so I tried passing the DEM as a > texture with "-t ". But the sub-tiles generated when viewed in OSG viewer > are totally white. I have confirmed this through code that it is generating > all the values as white. My DEM file format is tif and so are my textures, > but my textures subtile correctly so why can't my DEMs ? > >> > >> I'm using SUSE Linux 10.3, OSG-2.4, gdal-1.5.1, and vpb-0.9.7. Thanks > for your time. > >> > >> Renzil > >> _________________________________________________________________ > >> No Harvard, No Oxford. We are here. Find out !! > >> http://ss1.richmedia.in/recurl.asp?pid=500 > >> _______________________________________________ > >> osg-users mailing list > >> [email protected] > >> > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > >> > > > > > _________________________________________________________________ > Catch the latest fashion shows, get beauty tips and learn more on fashion > and lifestyle. > http://video.msn.com/?mkt=en-in > > > > _________________________________________________________________ > Catch the latest fashion shows, get beauty tips and learn more on fashion > and lifestyle. > http://video.msn.com/?mkt=en-in > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
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