4 bits textures on GeForce boards q?

back to the roots, i am using 16 colors indexed textures, and i was disturbed about some fillrates issues… In fact, my GeForce boards doesn’t seem to make strong differences by handling 4bits textures or 16bits textures into a scene!! so what?
when i specify GL_COLOR_INDEX4_EXT does OpenGL really uses 4bits data internaly or something bad happens?
any Nvidia coder around could help?
Please don’t tell me that this extension was patched to get more extension defines in the commercial package! )

We support paletted textures (8-bit) natively in HW, but the main purpose of using them shouldn’t be to save bandwidth, because (in some cases) they can actually hurt more than help; it’s difficult to say.

The real motivation for using them is as a form of texture compression – they can make your textures smaller, sometimes without hurting quality.

The shared texture palette is strongly preferred over a per-texture palette, and this goes for most other HW vendors as well.

  • Matt

Ok, but does Nvidia planned to support real 4bits textures with some new chipsets??
in the negative why does the 16 colors paletted extension is activated on boards wich can’t handle these textures formats???
i think it is confusing becoz when i get such an extension i would be pleased that it really works!!!

Not only do we not support 4-bit paletted textures, but I don’t know of anyone else who does.

Not a very interesting feature, in my opinion. Even 8-bit paletted textures are mostly a thing of the past.

  • Matt

Consider using S3TC texture compression instead. It’s 4bit/pixel but way higher image quality than a 16bit palettized texture.

things of the past???
oh my god!! using s3tc instead???
but what’s the point guys??
that’s non sense…
i am not agree with you, but it will be too long to explain…

Just a question?? are you using s3tc and/or 16 bits or above texture formats to map the 200,000 polys that can handle the GeForce 256 32Mb SDR at 60fps ??? you’re kidding!!

the features you’re talking about are Not interesting for TODAYS boards.

I know what i am saying, and why would i use more than 8bits to encode grayscale textures??? )

for more check out http://oks.merseine.nu

Originally posted by Sylvain:
[b]Just a question?? are you using s3tc and/or 16 bits or above texture formats to map the 200,000 polys that can handle the GeForce 256 32Mb SDR at 60fps ??? you’re kidding!!

the features you’re talking about are Not interesting for TODAYS boards.

I know what i am saying, and why would i use more than 8bits to encode grayscale textures??? )

for more check out http://oks.merseine.nu [/b]

Look, s3tc is just as fast or faster than 4bit palettized textures. Are you saying that s3tc is not interesting for todays boards? In my 3d engine under development it boosts performance by 60-70% over 16bit textures. BTW, you’ll have a hard time anyway to reach 60fps with 200000 polys on a GF. It’s theoretical limit is 15million triangles and you’ll need a lot of optimizations to reach 10million even non-textured.

wow

Originally posted by Sylvain:
I know what i am saying, and why would i use more than 8bits to encode grayscale textures??? )

I doesnt sound like you know what your saying. Of course you dont need more than 8 bits for encoding grayscale, but it sounds like you are talking about using a paletted texture for grayscale. Why not just use a 8-bit luminance texture. It will allow you to represent the entire 256 shade grayscale spectrum, and Im almost positive any hardware will store it natively as only 8-bits per pixel (no need to expand it to 16 or 32 bits) so it wont waste any memory. And I imagine it would perform better than a paletted texture too, but I cant speak for sure on that.

How about GL_LUMINANCE4 ?

S3tc, thins of the past??
Non sense!!
have a look at http://oks.merseine.nu (niouze graph section, second button on the tv)

textures are in 16 colors 4 bits textures, so what?? 32 bits & disco packing format are really necessary?? are you saying that a S3tc 25625616Bpp textured prim is fastest to a primitive textured with a shared palette texture?

it sounds strange & Not familiar to me?? and i am quite shocked to hear that 4 bits textures will not be supported in the future! that’s the same idea with an electronic notepad & the paper one!! when electricity is off you can still use a pen with the classic one!