Hi PaulB -- I looked at the data in Global Mapper and also see the "columns", so this doesn't appear to be a VPB issue, rather an issue with your data. -Paul
> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf > Of Paul Brewster > Sent: Friday, April 04, 2008 11:50 AM > To: OpenSceneGraph Users > Subject: Re: [osg-users] Anomalies using VirtualPlanetBuilder > > Thanks Jason, > > I guess the geo info was lost when I rescaled the image. > I'll include another GTiff with the info in it. The NODATA > value is -32767, which is the smallest value possible, of > course. I don't know the exact value of the bad areas, but > if you look closely, you can see craters on top of the > "plateaus", so I don't know if it is purely a NODATA problem. > > Thanks for the help. > > Paul > > Jason Beverage wrote: > > Hi Paul, > > > > I tried to take a look at the sample file you created, but > it doesn't > > have any coordinate system attached to it so can't reproduce the > > problems you were seeing with that data. > > > > My gut feeling is that it has something to do with the handling of > > NODATA values in osgTerrain. What are the actual pixel > values of the > > file you are using where the spikes are occurring? > > > > Thanks, > > > > Jason > > > > On Fri, Apr 4, 2008 at 10:29 AM, Paul Brewster > > <[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>> wrote: > > > > Hey all, > > > > I'm using VPB to build some terrains and have found a > few anomalies > > going on. I have a single 10240x10240 DEM of part of > the moon in a > > 16-bit unsigned format. I can run gdalinfo and > gdal_translate on it > > just fine, so I will include a 2.5% version of the DEM > so that you > > can see > > what I am talking about. When I run "osgdem -l 1 > --TERRAIN -d DEM.pds" > > everything works really well, except I get some areas > in the terrain > > that just don't look right. My nice round craters > suddenly jump out > > into plateaus in the middle. It appears that somebody put some > > monoliths in my moon craters. Does anybody know what > is happening here? > > These anomalies are consistent throughout the > levels, even if I > > go all > > the way down to full resolution. At first I thought > these might be from > > signed/unsigned problems. But as I look at the data, > I'm not convinced > > that is true. Anybody have any ideas what is going on? > I'll include > > some pictures to show what I mean. > > > > Thanks for your help. > > > > Paul Brewster > > > > Oh, and here is the vital information: > > OpenSceneGraph: 2.3.5 > > VirtualPlanetBuilder: 0.9.6 > > GDAL: 1.5.0 > > OS: CentOS 4.5 (linux) > > > > The header to my DEM: > > Driver: PDS/NASA Planetary Data System > > Files: LDEM20723Sm.LBL > > Size is 10240, 10240 > > Coordinate System is: > > PROJCS["POLAR_STEREOGRAPHIC MOON", > > GEOGCS["GCS_MOON", > > DATUM["D_MOON", > > SPHEROID["MOON_polarRadius",1737400,0]], > > PRIMEM["Reference_Meridian",0], > > UNIT["degree",0.0174532925199433]], > > PROJECTION["Polar_Stereographic"], > > PARAMETER["latitude_of_origin",-90], > > PARAMETER["central_meridian",0], > > PARAMETER["scale_factor",1], > > PARAMETER["false_easting",0], > > PARAMETER["false_northing",0]] > > Origin = (29.614999890327454,-29.614999890327454) > > Pixel Size = (59.229999780654907,-59.229999780654907) > > Corner Coordinates: > > Upper Left ( 29.6149999, -29.6149999) > > Lower Left ( 29.615, -606544.813) > > Upper Right ( 606544.813, -29.615) > > Lower Right ( 606544.813, -606544.813) > > Center ( 303287.214, -303287.214) > > Band 1 Block=10240x1 Type=Int16, ColorInterp=Undefined > > NoData Value=-32768 > > Offset: 1740000, Scale:0.6 > > > > > > > > > > _______________________________________________ > > osg-users mailing list > > [email protected] > > <mailto:[email protected]> > > > > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph. > > org > > > > > > > > > ---------------------------------------------------------------------- > > -- > > > > _______________________________________________ > > osg-users mailing list > > [email protected] > > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph. > > org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
