Vertex-texturing, use and performance?

[overclocked]

In the VS3 unit´s in NV40 do they have a texture unit "comparable" to the one in the fragmentpipe and/or what´s the difference? I heard something about 4 samples is this correct?

In term´s of use i think Chalnot refered to the nV "dev" guide, they mentioned IL2-Pacific Fighters using it for water(only game so far?).
I looked at some fps number´s with and without this feature enabled and there was quite some performance hit, whitout VS3 capable hardware from ATI so far or refresh from nVidia is it possible to make any judgement of the performance on NV40´s Vertextexturing and also possible improvement´s that can be made in R520 for ex.

As i also understand you can use this feature for clothes-animation and there was some demo PVR(?) that didn´t work first. Is it this kind of effect´s that this feature is useable for and will we see more of it in future engines, UE3 and Stalker comes to mind.

Last also as i don´t have VS3 capable hardware but love the IL2 series is there big quality difference in the water when using this feature?

 

[Xmas]

In the VS3 unit´s in NV40 do they have a texture unit "comparable" to the one in the fragmentpipe and/or what´s the difference? I heard something about 4 samples is this correct?

No, it's not comparable. Differences are:
- only 1- or 4-component FP32 textures
- only point sampling, no filtering
- LOD needs to be calculated in the shader
- fetch latency of ~20 cycles IIRC (PS: latency almost completely hidden)
- 4 texture samplers, i.e. up to 4 textures simultaneously (PS: 16)

You can find some more info here: http://developer.nvidia.com/object/using_vertex_textures.html

 

[overclocked]

Thanks but to the other question´s i have ex performance when turning it on and improvement(speculation´s) on future part´s there´s no answer right now i guess then before R5xx and some refresh of NV4x to determinate if it´s a bad implentation from NV or bad code then?

It would be nice to see some clothes animation demos from nVidia or maybe ATI when they launch SM3 hardware.

 

[Xmas]

Thanks but to the other question´s i have ex performance when turning it on and improvement(speculation´s) on future part´s there´s no answer right now i guess then before R5xx and some refresh of NV4x to determinate if it´s a bad implentation from NV or bad code then?

Next gen hardware will certainly show a huge improvement, but NV4x implementation is not as bad as to be unusable.


btw, what's wrong with your ´-key (or '-key for that matter)?

 

[DOGMA1138]

doesn`t EQ2 uses Vertex-texturing for the water allso?
the water in its highest mode uses some form of "waving flag" animation(yeah dont have any other means of discribing it).

 

[AlexV]

Wasn`t EQ2 SM1.1 only?

 

[overclocked]

Next gen hardware will certainly show a huge improvement, but NV4x implementation is not as bad as to be unusable.

It has been a while since looking at the fps with/without, actually the first review i read about Pacific-Fighters and looking at the IL-2 boards etz.
Maybe the performance has gone up significantly with new Forceware-driver´s.

btw, what's wrong with your ´-key (or '-key for that matter)?

hehe, i just use the buttons [i`m] used to..

 

[Xmas]

hehe, i just use the buttons [i`m] used to..

Seems just a tad too often to me

 

[overclocked]

doesn`t EQ2 uses Vertex-texturing for the water allso?
the water in its highest mode uses some form of "waving flag" animation(yeah dont have any other means of discribing it).

Do you have a link or something stated that because that is new to me if that is the case.

Wasn`t EQ2 SM1.1 only?

Nah, i remember the guy in the NV40 launch video stating SM3 and SM2. Most of the guys said SM3 bacause nVidia launched SM3 hardware then of course(PR).

 

[Jodi]

If you get down to the guts of it, vertex texturing allows you to have a fudge load of information available on a per vertex basis. The vertex texture could contain the actual vertex position, or could be used for vertex data compression or something. Heck, the PowerVR cloth demo uses the vertex texture to save physics info.

If people just think of a vertex texture as just another way of doing heightmaps, then they should look under the water for the rest of that iceberg.

 

[overclocked]

If you get down to the guts of it, vertex texturing allows you to have a fudge load of information available on a per vertex basis. The vertex texture could contain the actual vertex position, or could be used for vertex data compression or something. Heck, the PowerVR cloth demo uses the vertex texture to save physics info.

Very Interesting.
Btw you dont now if the PowerVR demo works on NV4x class hardware with the latest drivers or something, and if it still dont work what is the problem(code,incompability?).
I think i remember some Topic/thread when the NV40 launched, just about that "problem".

 

[Jodi]

If you get down to the guts of it, vertex texturing allows you to have a fudge load of information available on a per vertex basis. The vertex texture could contain the actual vertex position, or could be used for vertex data compression or something. Heck, the PowerVR cloth demo uses the vertex texture to save physics info.

Very Interesting.
Btw you dont now if the PowerVR demo works on NV4x class hardware with the latest drivers or something, and if it still dont work what is the problem(code,incompability?).
I think i remember some Topic/thread when the NV40 launched, just about that "problem".

The demo was written before any HW was available. I _believe_ that the NV40 didn't cap the texture formats used by the demo, and therefore didn't run. However thats all off the top of my head.

Kristoph?