Hi Bruno,
We also work with pointclouds in PointCloudViz ( www.pointcloudviz.com ) :) 2016-05-17 11:08 GMT+02:00 Bruno Oliveira <bruno.manata.olive...@gmail.com>: > I am rendering point clouds. > > What I want to do is to guarantee a certain point density is displayed. I > know the number of points in each LOD and I know the bounding boxes of > those LOD's. Can't I calculate a certain resolution value to pass to the > LOD? > > In the document I sent it states for PIXEL_SIZE_ON_SCREEN : "The current screen-space extent that OSG uses in this mode is determined by constructing a sphere that contains all of the model in question, then 3D projecting the diameter of the sphere into screen space and measuring the diameter in pixels." With respect to that it could be argued that a sphere projected in ScreenSpace ( perspective ) is an ellipse so it has 2 diameters. Anyway that measures are kind of orientative if you think in the major diameter it will work. So you need to assign ranges to your LOD's based on this assumption. You can try values ( i.e. from 500 to 1000 ) and tweak them iteratively. Anyway if you need a better understanding take a look to the traverse method of PagedLOD node ( https://github.com/openscenegraph/OpenSceneGraph/blob/master/src/osg/PagedLOD.cpp#L125 ) Hope it helps. > 2016-05-16 11:54 GMT+01:00 Bruno Oliveira <bruno.manata.olive...@gmail.com > >: > >> Thank you very much ! I understand very well the concept now, But I can't >> still figure out a good range value, and based on what >> >> 2016-05-16 11:13 GMT+01:00 Jordi Torres <jtorresfa...@gmail.com>: >> >>> Hi Bruno, >>> >>> Take a look to this document from Chris ( Alphapixel ) >>> http://alphapixel.com/wp-content/uploads/2015/04/LOD-Level-of-detail-in-OpenSceneGraph-OSG.pdf >>> . >>> It could shed some light on LODding. >>> >>> Cheers. >>> >>> 2016-05-16 12:03 GMT+02:00 Bruno Oliveira < >>> bruno.manata.olive...@gmail.com>: >>> >>>> Hello, >>>> >>>> I am using a LOD but I don't understand how PIXEL_SIZE_ON_SCREEN range >>>> mode works. >>>> >>>> >>>> I am doing >>>> >>>> lod->setRangeMode(osg::LOD::RangeMode::PIXEL_SIZE_ON_SCREEN); >>>> >>>> but what parameters can I use to configure this mode? >>>> >>>> _______________________________________________ >>>> osg-users mailing list >>>> osg-users@lists.openscenegraph.org >>>> >>>> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >>>> >>>> >>> >>> >>> -- >>> Jordi Torres >>> >>> >>> >>> _______________________________________________ >>> 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 > > -- Jordi Torres
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