Hi Andreas,
thanks a lot for your detailed answer. I will work through the example within one of the next holydays, as I am not a professional programmer (I´m a math teacher) and will need some quiet time for a demanding task like this. My software is a math-software to illustrate vector geometry, and thus displays planes and so on simply as polygons. That´s the reason I need two-sided materials (or at least I decided to do so, the alternative would have been to use more massive planes). For the time being it is a comfort for me that I didn´t make a simple mistake and that it is quite some work to adjust the StandardShadowMap to two-sided polygons.
Well... it depends. If the only trouble is incorrect back face lighting and lack of shadows from faces in front of light, then method could be simpler: 1. You can write your own shaders. I have read you already did that for ShadowMap. Then with small modification you could try using them with StandardShadowMap. This would give you the correct lighting I guess. Warning: if you want to adapt shaders made for ShadowMap make sure you change names of uniforms to match names used by StandardShadowMap (they use different naming convention). 2. To make sure both faces cast shadows simply call setMode( GL_CULL_FACE, OFF | OVERRIDE ) on your scene root stateset. This will force usage of both faces in shadow map rendering.
I hope this will let you reach the goal. But if you don't expect to use any more complex - view dependent techniques in the future then it would be easier to stay with ShadowMap. StandardShadowMap gives the same shadow precision. When one asks why there are two techniques doing the same then the answer is that StandardShadowMap lays foundation for more advanced techniques like MinimalShadowMap & LispSM variants. So, if one day you decide to switch to LispSM or MinimalXXXShadowMap then migration will be definitely simpler when you make your tweaks for StandardShadowMap.
Who maintains ShadowMap? I´d like the maintainer to do some tests with my shader. If you think it´s better than the standard one, I´ll refactor it into the Shadow-Map code. For a first impression, see the images in the last mail.
I guess that would be Robert. If you post the fixes on submissions lists all interested may work as your testers.
Regards & thanks for the example,
You're welcome. Wojtek _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
