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 _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
