[osg-users] Idea about shadows
Hi all, today I come over with an idea about avoiding an additional render pass for creating shadows. I highly appreciate any comments and maybe hints before I start with a trial implementation. I use deferred shading and my scene gets rendered in a prerender pass in order to get i.e. a depth map for various effects like ambient occlusion. I'd also like calculating shadows. The usual approach is adding an additional render pass with a camera located at the light position. This gives the depth texture from the light point. In the final shading pass, done from the final camera position, I need a matrix for calculating the actual positions depth from light point and compare it with the shadow maps depth. So I think I could do some comparable calculation in my prerender pass and create a shadow map manually without having the shadowmap prerender pass even when the actual camera position isn't at light position. This would be a very welcome speedup. Maybe I'm misleaded. So please kindly comment. Thank you ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Idea about shadows
I don't think it's possible: Shadowmapping need occlusion information that you cannot have without a prepass https://gamedev.stackexchange.com/questions/25436/shadows-in-deferred-rendering wernerM wrote: > Hi all, > > today I come over with an idea about avoiding an additional render pass > for creating shadows. > I highly appreciate any comments and maybe hints before I start with a > trial implementation. > > I use deferred shading and my scene gets rendered in a prerender pass in > order to get > i.e. a depth map for various effects like ambient occlusion. > I'd also like calculating shadows. The usual approach is adding an > additional render pass > with a camera located at the light position. This gives the depth > texture from the light point. > > In the final shading pass, done from the final camera position, I need > a matrix for calculating > the actual positions depth from light point and compare it with the > shadow maps depth. > > So I think I could do some comparable calculation in my prerender pass > and create a shadow map > manually without having the shadowmap prerender pass even when the > actual camera position > isn't at light position. This would be a very welcome speedup. > > Maybe I'm misleaded. So please kindly comment. > > Thank you > > ___ > osg-users mailing list > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > -- > Post generated by Mail2Forum -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=71649#71649 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
