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View Full Version : infinite shadow volumes demo posted



cass
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 -
Cass

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

cass
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 -
Cass

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

cass
04-07-2002, 06:11 AM
It works fine for me from several places.
What sort of error do you get?

DFrey
04-07-2002, 06:45 AM
Worked fine for me too. http://www.opengl.org/discussion_boards/ubb/smile.gif

knackered
04-07-2002, 06:45 AM
It works for me, but with some graphical glitches. The self shadow seems to flicker a bit.

cass
04-07-2002, 08:57 AM
knackered,

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

How would you resolve that problem?

Cass

knackered
04-07-2002, 09:21 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?

PH
04-07-2002, 09:22 AM
Cass,

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 ).

davepermen
04-07-2002, 10:13 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..

okapota
04-07-2002, 11:23 AM
it opens the page, but doe not download. the download doesnt start.

davepermen
04-07-2002, 11:38 AM
right click and "save target as" doesn't work?

okapota
04-07-2002, 11:32 PM
no. wierd, because the second link does.

cass
04-08-2002, 06:09 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.

thefirstbigd
04-11-2002, 12:06 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?