Hi Zach, No as it's polygonal geometry. My light is also a 3D object, not light point. For me this is approriate as they are small lights that would appear dimmer, and hence have less "glow", when seen far away.
Thinking about it lights like street lights might need to remain still quite bright as you move far away and the normal perspective foreshortening would reduce the glow too much. Regards, Simon _______________________________________________________________________ Simon Mills Modelling & Simulation Section (TEC-SWM) Tel: +31 (0)71 565 3725 European Space Agency (ESA/ESTEC) Fax: +31 (0)71 565 5420 Postbus 299, 2200AG Noordwijk e-mail: [EMAIL PROTECTED] The Netherlands http://simulation.esa.int _______________________________________________________________________ Zach Deedler <[EMAIL PROTECTED]> Sent by: To osg-users-bounces@ "'osg users'" openscenegraph.net <[email protected]> cc 09/01/2007 15:42 Subject RE: [osg-users] Light point depth Please respond to osg users <[EMAIL PROTECTED] negraph.net> Hi Simon, Looks good. If you zoomed in on one of the halos, would it shrink like a light point does? Zach -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Tuesday, January 09, 2007 03:22 To: osg users Subject: RE: [osg-users] Light point depth Yes, glow is uniform from all directions. Here's a screen snap to show how it looks in my application. The offset billboard trick was good enough for me avoiding the effort of hooking up specific run-time coding. I guess some kind of generic run-time interface could be constructed but of course would get progressively heavier the more light halos you have. (Embedded image moved to file: pic22312.jpg) Regards, Simon _______________________________________________________________________ Simon Mills Modelling & Simulation Section (TEC-SWM) Tel: +31 (0)71 565 3725 European Space Agency (ESA/ESTEC) Fax: +31 (0)71 565 5420 Postbus 299, 2200AG Noordwijk e-mail: [EMAIL PROTECTED] The Netherlands http://simulation.esa.int _______________________________________________________________________ Brad Colbert <[EMAIL PROTECTED] om> To Sent by: osg users osg-users-bounces@ <[email protected]> openscenegraph.net cc Subject 08/01/2007 23:03 RE: [osg-users] Light point depth Please respond to osg users <[EMAIL PROTECTED] negraph.net> Is the glow uniform from all aspects? The reason I ask this sounds similar to work I did for a lightpoint halo, which is uniform, but does not intersect with geometry and disappears when the light source is occluded. -B > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:osg-users- > [EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] > Sent: Monday, January 08, 2007 8:05 AM > To: osg users > Subject: RE: [osg-users] Light point depth > > I've had the same problem in the past and my solution, purely on the > modelling side, was to offset my glow polygon along the axes that points > towards the eye (+Y I think). Then the billboard is positioned at the > light source but the glow is drawn a little closer towards the eye. So > as you > look > more obliquely, the glow polygon is not immediately clipped in half. It > does > start to get clipped at some angle but the effect is much less serious. > For > me it was adequate for all my small lights in the scene and you might need > to > experiment with the offset distance which depnds on the light size. I used > the occlusion method too but only for really bright objects like the sun > with > lens flare etc. > > Regards, Simon > _______________________________________________________________________ > > Simon Mills > Modelling & Simulation Section (TEC-SWM) Tel: +31 (0)71 565 3725 > European Space Agency (ESA/ESTEC) Fax: +31 (0)71 565 5420 > Postbus 299, 2200AG Noordwijk e-mail: [EMAIL PROTECTED] > The Netherlands http://simulation.esa.int > _______________________________________________________________________ > > > > Roderick Kennedy > <Roderick.Kennedy@ > evos.net> > To > Sent by: osg users > osg-users-bounces@ <[email protected]> > openscenegraph.net > cc > > > Subject > 04/01/2007 17:26 RE: [osg-users] Light point depth > > > Please respond to > osg users > <[EMAIL PROTECTED] > negraph.net> > > > > > > > No now I think about it, that wouldn't work. What you need is for the > actual depth test to depend on the sprite centre, which can't be done > with the > usual > z-test. Sounds like the occlusion test is the way forward. > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Roderick > Kennedy > Sent: 04 January 2007 15:57 > To: osg users > Subject: RE: [osg-users] Light point depth > > How about a billboard sprite shader that takes z depth from the sprite > centre? > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Zach Deedler > Sent: 04 January 2007 15:37 > To: 'osg users' > Subject: RE: [osg-users] Light point depth > > Hmmm, looks like there is no simple solution. For now, I'll just try to > offset the light points more, and put the more elegant solutions on the > back > burner. Thanks for all the ideas everyone. > > > > Zach > > > > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Paul Martz > Sent: Thursday, January 04, 2007 10:17 > To: 'osg users' > Subject: RE: [osg-users] Light point depth > > > I don't care if the light point occludes objects within a few meters. > Would > using a PolygonOffset work with a meter offset? > I believe PolygonOffset won't work for you when viewing the light at an > obtuse angle, say from the side, and slightly in front of, the vehicle. In > such a case, the further headlight would need a greater depth offset than > the > near headlight to in order to completely avoid intersecting the vehicle > body. > > In general, whether PolygonOffset produces acceptable results or not > varies depending on available depth buffer precision, and how you've > set your near/far planes. > > Paul Martz > Skew Matrix Software LLC > http://www.skew-matrix.com > 303 859 9466_______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ > > _______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
