Hi Justo, Surfaces that are parallel to the light source will be subject to numerical aliasing issues that will mean that either the fragment is inside or outside that shadow map. You can't avoid these aliasing issues completely but if the vertex and fragment shaders are set up correctly then the parallel surfaces should in theory have the same ambient lighting regardless of being in the shadow or not so you shouldn't see the aliasing artifact.
I have just developed a new shadow technique that you'll find checked into svn/trunk, look for the ViewDependentShadowMap, use the --vdsm option in osgshadow example. All going well this will replace the collection of other shadow techniques. I would recommend testing against this new technique. Robert. On Thu, Aug 25, 2011 at 7:12 PM, Justo Ureña <[email protected]> wrote: > Hi, > > I´m testing diferent shadows techniques for my scene, and after some adjusts, > I got them working fine... Except for very big aliasing that appears in some > surfaces that are parallel to the light direction. It happens in all the > shadow maps techniques (ShadowMap, StandardShadowMap, LISPSM)... and I´ve > tried all the things that I could imagine to get rid of them without > success... Please, anyone can help me with that? > > From my investigation I got that the problem is that the depth map calculated > by the shadow camera does not fit exactly with the curved shape in the scene. > In the attachment you can see a render of the scene (that only includes the > cessna and a vertical directional light that produces the shadow) coloured > with the depth map. As you can see, in the laterals of the cessna appear > these withe stiches that means that the depth calculated in these texels of > the map is infinite, what is obviously wrong. There is any way to avoid this > annoying effect? > > Thank you very much! > > Cheers, > Justo > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=42241#42241 > > > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
