Hi Ralf, VPB couples terrain with imagery storing them in exactly the same .ive tiles.
Normarily one shouldn't have to tweak --radius-to-max-visible-distance-ratio, performance should be good without any tweaks, and should scale to terabyte databases. I found it pretty hard parsing your email thanks to all the acronyms so am not entirely clear on what your hardware set up. It may be that Delta3D is part of the problem, try building the VPB database and viewing using osgviewer to see if there is performance delta. Use of Windows for a visual simulator is not something I would recommend, the file system performance sucks big time, memory management and threading support is not great either. Install a modern Linux and you'll probably find many of your issues gone. I'd also recommend an upgrade to OSG-2.4 as the DatabasePager has been improved w.r.t load balancing, keeping memory consumption much more even. OSG-2.4 also offers improvement to osgTerrain, such that one can now control the sample density of elevation data via the osgTerrain::Terrain class, to generate such databases you'll need to build using SVN version of VPB and use the --terrain option. Robert. On Fri, May 16, 2008 at 8:44 AM, Ralf Stokholm <[EMAIL PROTECTED]> wrote: > Hi > > Im working on a flight simulator project and have been using VTP to generate > a terrain for visualisation, The input data is 30m landsat orthofoto and 90 > m nasa elevation data. In addition there are som higher resolution orthofoto > for specifik target areaes dovn to 25 cm resolution. > > My application has a Targeting POD displaying in the cockpit in adition to > the standart otw view, the problem is that I have a hard time getting it to > run smothly. To keep good quality in the TGP view I had to increase the > --radius-to-max-visible-distance-ratio from default 7 to 25 in order to get > the orthophoto to load early enough in my zoomed targeting pod view. I I > generate the terrain without height date it almost runs smooth at that > setting, but with elevation data it studders all the time. Especially when > turning my head. > > Im using the delta 3d engine and the allocate 4ms for paging opperations > each frame. > > This is tested on a brand new system Core2 duo 3.0 Ghz 4 Gb RAM and a > geforce 9800 GTX, it has a raid0 hard drive etc so I cant emagine this it > the limiting factor. Oh its running windowsXP sry :( > > OSG is verison 2.2.0 and VTP is version 0.9.1 > > The aplication is rendered on 2 displays a 1920x1200 display for the cockpit > TGP view is roughly 512x512 ans a 1920x1080 display for external view. > > The following is the command line used for generating the terrain archive. > > osgdem -d height -t texture -l 20 --radius-to-max-visible-distance-ratio 25 > -v 1.1 --cs "+proj=laea +lat_0=55.5 +lon_0=9.5 +x_0=0 +y_0=0 +datum=WGS84 > +units=m +no_defs" -o denmark.ive -a denmark.osga > > Is there any way of making the terrain load later in the OTW view? Or any > other hints on what parameters to play around with to improve the performace > of this? > > > Brgs > > Ralf Stokholm > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
