Hi everyone !
I found shadow shader on N-Vidia : YOu can see it :
http://developer.download.nvidia.com/SDK/9.5/Samples/effects.html#fpShadowits name is : FpShadow, it make the shadow on itself.
You can download the theology :
http://developer.download.nvidia.com/SDK/9.5/Samples/MEDIA/docPix/docs/FX_Shadowing.pdfBut this fx file seem very strange!
It's ot like some fx file that I read before!
how to apply it in 3dgs ? and how to convert it into fx file of 3dgs ?