View Full Version : infinite shadow volumes demo posted

04-04-2002, 04:05 PM
Hi all,

One of the shadow volumes demos associated with this paper (http://developer.nvidia.com/view.asp?IO=robust_shadow_volumes)
have been posted here:

infinite_shadow_volumes__exe.zip (http://cvs1.nvidia.com/demos/infinite_shadow_volumes__exe.zip)

infinite_shadow_volumes__src.zip (http://cvs1.nvidia.com/demos/infinite_shadow_volumes__src.zip)

There will be a "real page" soon, but you can go ahead and download from here if you're interested.

Thanks -

04-04-2002, 04:23 PM
Well, finally it appears. I have waited for it weeks.
Thank you!

04-06-2002, 04:45 PM
Ugh. The cvs1.nvidia.com server seems to be having trouble. I've put these files on my personal server for the time being:

r3.nu/~cass/nv/infinite_shadow_volumes__exe.zip (http://www.r3.nu/~cass/nv/infinite_shadow_volumes__exe.zip)

r3.nu/~cass/nv/infinite_shadow_volumes__src.zip (http://www.r3.nu/~cass/nv/infinite_shadow_volumes__src.zip)

Thanks -

04-07-2002, 05:03 AM
i think your new src link doesnt work either.

04-07-2002, 07:11 AM
It works fine for me from several places.
What sort of error do you get?

04-07-2002, 07:45 AM
Worked fine for me too. http://www.opengl.org/discussion_boards/ubb/smile.gif

04-07-2002, 07:45 AM
It works for me, but with some graphical glitches. The self shadow seems to flicker a bit.

04-07-2002, 09:57 AM

It is an interesting artifact of vertex lighting on a smooth shaded surface with shadow volumes.

How would you resolve that problem?


04-07-2002, 10:21 AM
Haven't digested the new shadow volumes paper yet, but I can't remember getting those artifacts using the standard method. What are they caused by?

04-07-2002, 10:22 AM

It's even a problem with per-pixel lighting. The only thing that would truly work is using models where the normals follow the actual curvature more closely. I use Mark Kilgards steep ramp for self shadowing ( a less steep version of it ).

04-07-2002, 11:13 AM
there are three ways:
1) us a higher res mesh so the bug gets less big.
2) use flatshading (you can use smoothshading but send for every triangle the triangle normal, looks nearly like perpixellighting for the diffuse part, much bether than flatshading after all..
3) use an approximated shadow-volume with approximates the same way smooth shading does: act per vertex. the demo is wellknown on the nvidiapage for dx existing, the one where you have to add degenerated triangles. with this it should work quite ok..

oh, just one note. why do you get shadow-problems? because you yet shadow the object by itself because of the vertex-lighting AND then you draw a shadow over the shadow.. means twice shading.. you have to get rid of at least one..

04-07-2002, 12:23 PM
it opens the page, but doe not download. the download doesnt start.

04-07-2002, 12:38 PM
right click and "save target as" doesn't work?

04-08-2002, 12:32 AM
no. wierd, because the second link does.

04-08-2002, 07:09 PM
The links on for both the demo and the whitepaper are being updated on developer.nvidia.com. The cvs1 server will be back up later this week.

04-11-2002, 01:06 PM
Cass, I don't understand the problem exactly, but if you don't have normals which are different to the face normal, you don't get problems?