Volume texture support in current cards

[Mark R]

A current project I'm working on needs quite extensive volume texture support from the hardware.

I was developing it on an old Radeon 9700 - and in general the support isn't bad (subject to the limitations of only having 128 MB of onboard RAM).

I recently tried to move my development to a more recent card (GeForce 6900) only to find that the support is inadequate (maximum texture size 256 pixels) with a number of bugs.

Does anyone know if this has been addressed in the later 7900 series cards?

Alternatively I suppose I could change to a X1900 as I'd expect the support to be at least as good - but I've heard that the performance isn't as good as the 7900s.

 

[imported_Crusader]

Theres only one forum member here with the knowledge to answer your question, PM Gstanfor.

 

[Zstream]

Originally posted by: Crusader
Theres only one forum member here with the knowledge to answer your question, PM Gstanfor.

LMFAO I think that he has proven to be more of a moron then anything. Atleast by his recent post.

 

[BassBomb]

what do you mean ? could you re-explain

because i know 256x256 is not the maximum size of textures for tons of video cards if thats what u meant

 

[Munky]

These are volume textures, also known as 3d textures. So at 256x256x256 it would take up some considerable chunk of memory.

*edit: and to just give you an idea of the mem requirements, a 256^3 32-bit texture would take up 64MB of video memory. The next level up would be 512^3, and that texture would take up 512MB of video memory.

 

[lifeguard1999]

Originally posted by: munky
These are volume textures, also known as 3d textures. So at 256x256x256 it would take up some considerable chunk of memory.

*edit: and to just give you an idea of the mem requirements, a 256^3 32-bit texture would take up 64MB of video memory. The next level up would be 512^3, and that texture would take up 512MB of video memory.

One application for 3D textures is for quick volume rendering. We do this all the time. Looks like Gstanfor isn't the only one here with that knowledge.

 

[imported_Crusader]

Originally posted by: lifeguard1999

Originally posted by: munky
These are volume textures, also known as 3d textures. So at 256x256x256 it would take up some considerable chunk of memory.

*edit: and to just give you an idea of the mem requirements, a 256^3 32-bit texture would take up 64MB of video memory. The next level up would be 512^3, and that texture would take up 512MB of video memory.

One application for 3D textures is for quick volume rendering. We do this all the time. Looks like Gstanfor isn't the only one here with that knowledge.

nah, he'll be able to add in more than anyone here knows. he always does when the real questions are posted with actual verifiable answers relating to video cards..
and he tends to also lean towards Nvidia..
correlation?

 

[Gstanfor]

I really don't know all that much about 3d Textures other than they rarely see useage in 3D games because of the resources they require. Technically they are known as volumetric textures.

As far as nVIDIA suuport for them, I believe it was first introduced with the GeForce3 series, and nVIDIA licensed the compression scheme to Microsoft for use in DirectX, so nVIDIA bugs sound somewhat suprising, I'm going to guess ATi has taken liberties with the standard which fall other on other hardware.

I'd try using OpenGL instead of DirectX, and also a Quadro rather than a GeForce if this is a serious, business oriented application. BTW, I don't think you are using a 6900, perhaps a 6800 or a 7900 of some description?

The nVIDIA Grace Demo makes use of volumetric texures : "3D textures are used for animating the sparkles on her dress"

Technical Brief: NVIDIA nfiniteFX Engine: 3D Textures

 

[BFG10K]

LMFAO I think that he has proven to be more of a moron then anything. Atleast by his recent post.

You'll notice it was Crusader making that post. This is the guy that registered and jumped straight into the AEG thread to defend the shills like Rollo.

 

[Mark R]

Originally posted by: Gstanfor
As far as nVIDIA suuport for them, I believe it was first introduced with the GeForce3 series, and nVIDIA licensed the compression scheme to Microsoft for use in DirectX, so nVIDIA bugs sound somewhat suprising, I'm going to guess ATi has taken liberties with the standard which fall other on other hardware.

Entirely possible that that's the case. I'd only tried developlemt on my ATI until recently. There were a number of things I had to change to get the code to nVidia hardware. The most frustrating was the difference in preparing dynamic volume textures on the 2 hardware systems - I just had to use trial and error to find code that would work.

I'd try using OpenGL instead of DirectX, and also a Quadro rather than a GeForce if this is a serious, business oriented application. BTW, I don't think you are using a 6900, perhaps a 6800 or a 7900 of some description?

You're right, I meant 6800 - sorry. A slight slip. You're not the first person to suggest I use OpenGL, but I prefer .NET to other frameworks, so am a bit limited - as there aren't any official OGL libraries for it.

My app is meant to perform volume rendering (among other things) of big datasets (My radeon only goes up to 512^3 before it runs out of VRAM. This isn't quite all the data, but it's close enough).

I don't intend to do any serious work with it - or to market it as a serious product. It's meant to be a free/almost free alternative to some very, very expensive workstation software.

But I'm sure you're right - I suspect that this sort of rendering is far better supported on the quadro series of cards. But, from my POV, the quadros are a lot more expensive than the equivalent geforce cards.

 

[Gstanfor]

I suspect a video card with a larger memory may prove beneficial for you. You maybe able to test that theory with a cheap 6200 Turbo Cache card, where system ram can be used as though it were video card ram (not sure if it will work for volumetric textures though - I'm thinking it should).