3Dc

[Bjorn]

if 3dc is so similar to dx5 then why is it necessary to have hardware support? why can't other cards do it. why did ati bother to hardware support it?

Because 3DC gives better quality. Although i don't know by how much though since we haven't seen any comparisions.

 

[DemoCoder]

Is D3DFMT_CxV8U8 covered by a patent too?

I believe that the idea of storing a normal map using only 2 dimensions and infering the third is patented... but then, the whole 'DOT3' idea of doing fast bump mapping in a local surface coordinate system using a (3D) normal map is patented too. <shrug>

I've hated algorithm patents ever since the XOR cursor. Argh!

 

[Simon F]

Everything can be seen as an algorithm - whether it's obvious AT THE TIME OF FILING is another matter.

 

[jvd]

Yes it does matter, because if it's just marginally better (visualy or performance speaking) then it won't be used.

But if 3Dc is there and it gets used the game will look better. Surely there can be no objection to that...

Yeah you are right. But the question is, does it really looks much better than DXT5? I'm still waiting for a direct comparison.

does it matter ? one is getting pushed the other is not . Even if they look the same the one that is being pushed gets my vote

dxtc5 isn't being used . No one is pushing it . You may even have to pay for it under open gl .

So if 3dc even only looks better 10% of the time but its actually being pushed to be used then its much better than a 4 year old dxt5 that hasn't been used since it came out

 

[Evildeus]

Why should we pay for it under OGL? And i thought the patent issue was on 3dc

 

[jvd]

Why should we pay for it under OGL? And i thought the patent issue was on 3dc

Same reason why there are things u need to pay nvidia for under open gl .

Same reason why u need to pay s3 to use dxtc under opengl . (or did at one point )


You make me laugh.


Nvidia has been pushing thigns out in their own cards and exposing them as caps or extensions that others need to pay for , for years . Yet you have a big issue with 3dc ? Why because its ati ?

YOu shouldn't be pissed at ati for this you should be pissed at all the companys that have done thigns like this before .

 

[Bjorn]

Same reason why u need to pay s3 to use dxtc under opengl . (or did at one point )

And everybody already does this, so why would they need to pay extra for DXT5 ? i thought it was a part of the orginal DXTC spec.

 

[jvd]

Same reason why u need to pay s3 to use dxtc under opengl . (or did at one point )

And everybody already does this, so why would they need to pay extra for DXT5 ? i thought it was a part of the orginal DXTC spec.

right dxtc5 isn't gdc though. Read the paper . Gdc offers improvements over dxtc5 .

Also no one is using dxtc5

 

[Bjorn]

right dxtc5 isn't gdc though. Read the paper . Gdc offers improvements over dxtc5 .

But the question was if you had to pay for DXT5 under Open GL. And yes 3DC offer improvements but who has questioned that ?

Also no one is using dxtc5

And no one is using 3Dc at the moment.

 

[Evildeus]

Why should we pay for it under OGL? And i thought the patent issue was on 3dc

You make me laugh.

Hmm, have a good lauch but you didn't answer my question. Thanks Bjorn

 

[jvd]

right dxtc5 isn't gdc though. Read the paper . Gdc offers improvements over dxtc5 .

But the question was if you had to pay for DXT5 under Open GL. And yes 3DC offer improvements but who has questioned that ?

Also no one is using dxtc5

And no one is using 3Dc at the moment.

I know u did at one point and I'm assuming that you still have to pay for it . Its under dx that it is free .

I have not been able to find any current info .

But hey if it is free under open gl why isn't anyone using it


For that matter why aren't they using it in dx where we know its free.

Perhaps it just sucks and thus gdc should replace it .

 

[John Reynolds]

And no one is using 3Dc at the moment.

But knowing without a doubt that game developers are supporting it for games due this year is something to consider. IMO.

 

[Bjorn]

But knowing without a doubt that game developers are supporting it for games due this year is something to consider. IMO.

Of course. But supposedly, you could use DXT5 for cards that doesn't support 3Dc and with (according to Ati) good results. And we have yet to see the difference between DXT5 and 3Dc.

 

[Sabastian]

But knowing without a doubt that game developers are supporting it for games due this year is something to consider. IMO.

Of course. But supposedly, you could use DXT5 for cards that doesn't support 3Dc and with (according to Ati) good results. And we have yet to see the difference between DXT5 and 3Dc.

Well then.. ATi has support for 3Dc which has reportedly better quality results, granted only marginally better then DXT5.(according to some.) ATi is pushing their hardware supported 3Dc. NV ought to ether take on the 3Dc speck or push DXT5 to developers. I don't see why ATi ought to have to push the DXT5 for teh sake of their competitors since indeed DXT5 will run on ATi parts as well. ATi already supports DXT5 and 3Dc. I think if NV wants compression bla blas then they ought to get out there and get it from their TWIMTBP partners. DXT5 and 3Dc are not on even footing 3Dc is reportedly supperior. If competitors want DXT5 compression development and not 3Dc then they ought to push for it. This whole matter sounds a tad like sour grapes because ATi was actually able to get developers to start to support 3Dc which is an open standard that other IHVs are free to support. Sure go ahead get developers to use DXT5 but don't expect ATi to evangelize it because their competitors don't have hardware 3Dc support yet.

 

[GameCat]

You seem confused jvd. Since 3Dc is such a minor variation on S3TC (which is called DXTC in Direct3D), you would probably need an S3 license to support it in your OpenGL driver. I fail to see how this is much of an issue however, as all major players already support S3TC in OpenGL and therefore already has a license from S3. You don't need a license to support it in Direct3D since Microsoft has a license covering all D3D drivers.

As a sidenote I find it interesting how many of the people that claim PS/VS 3.0 won't make a difference in games for the next few years because of weak hardware support also think 3Dc is the second coming. 3Dc is nice and all, but it really is a pretty minor feature. A clever tweak of S3TC to handle normal maps as far as I can tell.

 

[Sabastian]

As a sidenote I find it interesting how many of the people that claim PS/VS 3.0 won't make a difference in games for the next few years because of weak hardware support also think 3Dc is the second coming. 3Dc is nice and all, but it really is a pretty minor feature. A clever tweak of S3TC to handle normal maps as far as I can tell.

Yeah, it is not as though compression tech is new or anything like that. But if ATi successfully markets 3Dc and gets wider developer support it would mean substantial IQ improvements with little performance hit. That would be a major selling point... if it takes off and it might not be too far away unlike PS3.0, not that PS3.0 means much in the way of superior IQ over PS2.0.

 

[Bjorn]

..I don't see why ATi ought to have to push the DXT5 for teh sake of their competitors since indeed DXT5 will run on ATi parts as well. ATi already supports DXT5 and 3Dc.

Of course they don't and nobody has said that either. The thing is, it's Ati who came up with the fallback for DXT5 so they're in actuality the one that's pushing it. Which is a big kudos to Ati imo and of course great for all their R3XX owners.

 

[Sabastian]

..I don't see why ATi ought to have to push the DXT5 for teh sake of their competitors since indeed DXT5 will run on ATi parts as well. ATi already supports DXT5 and 3Dc.

Of course they don't and nobody has said that either. The thing is, it's Ati who came up with the fallback for DXT5 so they're in actuality the one that's pushing it. Which is a big kudos to Ati imo and of course great for all their R3XX owners.

Well then NV ought to take a hold of that and push ATi's fallback to developers too.

 

[Bjorn]

Well then NV ought to take a hold of that and push ATi's fallback to developers too.

For all we know, they might already be doing that. But they have other things on their agenda, like SM3.0 f.e , so i'm thinking that since Ati is pushing it, they won't bother that much.

 

[Sabastian]

Well then NV ought to take a hold of that and push ATi's fallback to developers too.

For all we know, they might already be doing that.

Great then.. so why is this such a debate? Because 3Dc is a superior implement that ATIs competitors don't support yet even though it is an open standard. I will be interested in seeing though what the disparities are though if any. If 3Dc does not produce substantial differences then it might fail as an industry standard because it requires hardware in favor of DXT5 which is reportedly an inferior compression implement. Lets hope NV swallows their pride and indorses the fallback at any rate.