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corpus chaos
03-19-2003, 03:46 PM
Hi everyone, today i want to discuss about shadow effects. Before this, i'v etried something that can produce a "fake shadow" and it still didn't represent better, i'm just playin' with textures, so if anyone that know 'bout it reply to me k.

oliii
03-19-2003, 06:25 PM
the simplest solution is projecting the geometry on a plane http://www.opengl.org/discussion_boards/ubb/Forum2/HTML/012195.html

a less simple solution is projecting a texture on the geometry
<no link> (you basically render the geometry potentially in shadow twice with an altered texture matrix and the shadow texture).

a more complicated method is based on stencil shadows (z-pass stencil shadow) http://www.opengl.org/developers/code/mjktips/rts/

an even more complicated algorithm uses depth buffers to solve the problems associated with projected texture. http://developer.nvidia.com/view.asp?IO=Shadow_Map

an even even more complicated algorithm is based on John Carmack's approach, z-fail stencil shadow, to solve issues with the z-pass stencil shadows http://developer.nvidia.com/view.asp?IO=cedec_stencil

everything is covered in there http://developer.nvidia.com/view.asp?IO=docs_shadows


[This message has been edited by oliii (edited 03-19-2003).]