Re: [osg-users] blend vpb osgGIS models
On Jan 7, 2008 4:12 AM, Glenn Waldron [EMAIL PROTECTED] wrote: However, it only works for areas of limited geographic size. Overlaying a geocentric model onto a geocentric globe using osgSim::OverlayNode doesn't work for projecting models that cover larger areas or the entire earth. Robert may be able to shed some light on why this is the case. The limitation comes down to use of projective texturing - it can't wrap around the globe. The view dependent OverlayNode modes can cope better as they clamp the projected region to what is visible on screen. Robert, ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] blend vpb osgGIS models
Thanks Robert, that makes sense. There are still issues when using view dependent mode though. My initial thought was to grid up the geometry to be projected and then apply cluster culling to each cell, so that it would only consider projecting Visible geometry. However the cluster-culling doesn't seem to operate as I expected in this context, i.e., on the geometry to be rendered to texture. Does an RTT camera consider cluster culling the same way a normal camera does? Or am I barking upt he wrong tree? Thanks. -gw On Jan 7, 2008 4:17 AM, Robert Osfield [EMAIL PROTECTED] wrote: On Jan 7, 2008 4:12 AM, Glenn Waldron [EMAIL PROTECTED] wrote: However, it only works for areas of limited geographic size. Overlaying a geocentric model onto a geocentric globe using osgSim::OverlayNode doesn't work for projecting models that cover larger areas or the entire earth. Robert may be able to shed some light on why this is the case. The limitation comes down to use of projective texturing - it can't wrap around the globe. The view dependent OverlayNode modes can cope better as they clamp the projected region to what is visible on screen. Robert, ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- Glenn Waldron : Pelican Mapping : http://pelicanmapping.com : 703-652-4791 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] blend vpb osgGIS models
Hi! I am learning about the VirtualPlanetBuilder and osgGIS, both are necessary for the Geography Infomation system, I want to know how to use them together, When I use the osggis_viewer application, I cannot find the right way to display the osgGis models and VPB models together, my data include global image, dem and the world courtys polygon vector. I want to add the vector as a layer, and blend the vector with the terrain and adjust the transparency. Can I did that using osgGIS? Any one can tell me the right way. Thanks. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] blend vpb osgGIS models
MingWei, It sounds like what you are trying to do it to drape the country polygon geometry onto a VPB globe. I assume you are using geocentric whole-earth models. Usually you can drape the polygon geometry to the terrain using an osgSim::OverlayNode. Here is a screenshot showing the technique in action: http://osggis.org/wiki/index.php?title=Image:States2.jpg However, it only works for areas of limited geographic size. Overlaying a geocentric model onto a geocentric globe using osgSim::OverlayNode doesn't work for projecting models that cover larger areas or the entire earth. Robert may be able to shed some light on why this is the case. In any case, the way to view overlays in osggis_viewer is with the --overlay parameter, like this: osggis_viewer terrain.osga --overlay features.osga (Note, I am cross-posting this to the osgGIS mailing list.) -gw On Jan 6, 2008 8:38 PM, MingWei [EMAIL PROTECTED] wrote: Hi! I am learning about the VirtualPlanetBuilder and osgGIS, both are necessary for the Geography Infomation system, I want to know how to use them together, When I use the osggis_viewer application, I cannot find the right way to display the osgGis models and VPB models together, my data include global image, dem and the world courtys polygon vector. I want to add the vector as a layer, and blend the vector with the terrain and adjust the transparency. Can I did that using osgGIS? Any one can tell me the right way. Thanks. -- 网 易 有 道 词 典 －－ 全 球 最 强 大 的 免 费 英 汉 互 译 词 典 （ 只 有 2 兆 ） http://event.mail.163.com/chanel/click.htm?from=NO_25domain=163 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- Glenn Waldron : Pelican Mapping : http://pelicanmapping.com : 703-652-4791 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
