Futuremark: 3DMark06

OpenGL guy said:
Just because 8 samples lie within, or out of, the shadow doesn't mean all 16 will! A better solution is to generate an edge mask so that only pixels within the edge mask get all 16 samples. Pixels outside the edge mask only need 1 sample to determine whether they are shadowed or not.
Just because a pixel isn't inside the edge mask doesn't mean it's not a penumbra pixel. If you take 8 "outer" samples first, the results are likely very similar to those of an edge mask. And generating an edge mask needs sampling from the shadow map, too.
 
Vysez said:
I think it's time for Ati to admit that they lost the IQ crown in favor of the technologically superior nVIDIA™ cards.

This bug on a particular surface in a particular test of 3DMARKS 2006™ is a clear indicative that Ati are not only cheating with their drivers, but are also deceiving their customers, their friends and all the humankind, plus Rys (Since he's not exactly a part of the humankind, he's like an evolved hamster according to some folks).

Here's another unrelated and inconclusive anedoctical evidence to go with the TR one, the other day I saw an ati logo in a magazine, and the logo had clearly image quality issue, like color dithering or something.
You know what that means? Ati cheats with their Drivers. Yeah, even the paper drivers!

I think it's time to call for a general boycott of all Ati products. i'm starting an Online Petition right away!

And before someone points out that it's maybe a simple anecdotical driver bug, and that the TR wanted a few cheap clicks. Let me tell you this you folks of little faith,... You're probably right.
Well said mate :D
 
Jawed said:
It seems to me that the edge map encompasses the entire penumbra, rather than being "1 pixel" thick along "edges".
That's not what I meant. As you are using a finite resolution shadow map, you can miss "single pixel penumbras". It's almost the same with taking 8 "outer" samples first.

btw, your link doesn't work.
 
I corrected the link - copy and pasting from another posting used the truncated-display version :cry:

I can't figure out what a single pixel penumbra is. Is that a penumbra that should be one pixel wide? Or do you mean penumbras due to particles? :oops:

Jawed
 
I mean a penumbra that is just (less than) a single pixel wide. Both approaches have the same problem: sampling gaps.
 
Thanks.

What's puzzling me is whether these algorithms are attempting to vary the penumbra width as the depth-ratio: light-blocker/light-receiver varies. The edge map on page 21 sort of looks like it varies in thickness.

It seems to me that the kernel should vary in diameter as the ratio changes. I'm not sure if that would help with the < single pixel penumbra problem, though.

Jawed
 
Hexus up with a long, thotful analysis: http://www.hexus.net/content/item.php?item=4599

There are many interesting points, technical and, err "political" (for lack of a better term) to point at, but from a summarization pov what really struck me as "the money shot" is about mid-article:

Can you reasonably engineer a faithful and unbiased "Gamer's Benchmark" under those conditions? I'd argue that you reasonably can't. The compromises you have to make would be too polarised, and I think that's entirely visible with 3DMark06.
 
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