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JelloFish
10-10-2002, 10:50 AM
Hi ive tried to switch over the shadow rendering to use render to depth texture rectangle but rendering to texture still seems orders of magnitude slower than copytexsubimage. The difference in framerate is something like 30fps with copytexsubimage, and 5fps render to texture. Does anyone have any ideas why this might be?

davepermen
10-10-2002, 11:21 AM
because nvidia drivers implemented rendertotexture crappy. but, according to cass, it should change in the next release.. i hope (and bet http://www.opengl.org/discussion_boards/ubb/biggrin.gif) its true. wish us all the best http://www.opengl.org/discussion_boards/ubb/biggrin.gif

(oh, and i hope rendertotexture stops to be buggy as well http://www.opengl.org/discussion_boards/ubb/biggrin.gif)

JelloFish
10-10-2002, 12:15 PM
Does that mean the beta 40.71's as well?

Asgard
10-10-2002, 12:25 PM
Yes, see this thread: http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/007527.html

JelloFish
10-10-2002, 01:39 PM
Thanks Asgard. I guess that thread was just a couple days ago so maybe if we are lucky we can see fast (like it is in d3d) RTT (or RTT Rectangle) in 1 - 2 weeks.

V-man
10-10-2002, 07:36 PM
Is this problem only on nvidia cards. Never mind very old cards that don't support multitexturing and cubemapping, and such.

V-man

Humus
10-10-2002, 07:40 PM
Originally posted by V-man:
Is this problem only on nvidia cards.

AFAIK, yes. At least on Radeon series cards it's very fast. For instance do my "Shadows that don't suck" demo run at like 4x as high framerate on a R8500 than a GF3.

V-man
10-12-2002, 08:18 AM
Originally posted by Humus:
AFAIK, yes. At least on Radeon series cards it's very fast. For instance do my "Shadows that don't suck" demo run at like 4x as high framerate on a R8500 than a GF3.

Unfortunatly, I dont have access to any Radeon series cards.

Can you tell me if it's actually faster than plain vanilla copysubtex or ....

It should be in principal.

V-man

JelloFish
10-18-2002, 07:44 AM
Hey humus what extensions are you using in "shadows don't suck", on the ati website http://www.ati.com/developer/sdk/radeonSDK/html/info/Prog3D.html it doesn't have any shadow extensions there. Is the page just out of date?

NitroGL
10-18-2002, 09:05 AM
Originally posted by Humus:
AFAIK, yes. At least on Radeon series cards it's very fast. For instance do my "Shadows that don't suck" demo run at like 4x as high framerate on a R8500 than a GF3.

Yeah, it's faster, but it's not with out it's own problems unfortantly (like the cull face was wrong at one point, but I think that fixed now).

BTW, when is your site going to be back up?

Humus
10-18-2002, 01:04 PM
Originally posted by JelloFish:
Hey humus what extensions are you using in "shadows don't suck", on the ati website http://www.ati.com/developer/sdk/radeonSDK/html/info/Prog3D.html it doesn't have any shadow extensions there. Is the page just out of date?

It's true that that page is outdated/incomplete, but it's also true that I don't use any shadow extensions. I render to normal 32bit cubemaps. For a quite simple scene like the one in that demo it's enough precision. The shadowmap compare is done in a fragment shader / register combiner.

Humus
10-18-2002, 01:06 PM
Originally posted by NitroGL:
Yeah, it's faster, but it's not with out it's own problems unfortantly (like the cull face was wrong at one point, but I think that fixed now).

BTW, when is your site going to be back up?

Yeah, that affected an old demo of mine. It was fixed long ago though, aswell as the demo as it was because of this problem culling the wrong faces.
My site will be up again soon. The server doesn't have any case right now, but it's on it's way. It's been shipped, but haven't yet arrived. Probably early next week.