Why SSAA and DX10 cen't work together In HD58X0 ?

[Novum]

Texture filtering only ensures that the value coming out of the texture unit is not aliased

And not even that is guaranteed, because the IHVs are "optimizing" the filters...

DirectX doesn't really provide any particular tools to deal with this problem.

What about running the shader at sample rate? That's supported in 10.1 and 11.

 

[Humus]

What about running the shader at sample rate? That's supported in 10.1 and 11.

Sure, but it's not a final solution by any means, just like increasing resolution isn't. It usually just makes it a smaller problem.

 

[fellix]

[PCGH] 55 in-game screen shots comparing ATi's SSAA

 

[Xenus]

There seem to be some anomalies in those screens. Especially in the one of the earlier flatout screens where the stepping on the exhaust on the underbelly of ther car is really noticeable.

 

[Graham]

There seem to be some anomalies in those screens. Especially in the one of the earlier flatout screens where the stepping on the exhaust on the underbelly of ther car is really noticeable.

Flatout renders a lot of it's effects (such as all the particles) at lower resolution to save fillrate, etc.

 

[Xenus]

Even body detail? I could see the exhaust particles but the fact the the stepping on the pipe looks that bad seems weird.

 

[fellix]

FlatOut screens are full of "residual" aliasing, sort of. Most notably on thin objects like the hanging high voltage wires and some hi-contrast surface edges -- the car's wheels, for instance.

 

[Mintmaster]

Even body detail? I could see the exhaust particles but the fact the the stepping on the pipe looks that bad seems weird.

Don't forget that you have to composite that quarter resolution buffer with the z-buffer, which is probably downscaled.

Can you point out the screenshot that you're talking about? I'm just guessing based on the posts.

 

[Xenus]

There are a few that didn't quite seem to fit but this is one of the one's where it's most noticeable.

 

[Mintmaster]

There are a few that didn't quite seem to fit but this is one of the one's where it's most noticeable.

Yup, that's due to exactly what I described earlier. When you draw a 1/4 resolution alpha buffer, you have to draw it into a quater resolution Z-buffer, or else the alpha geometry will simply lay on top of other geometry rather than intersect it (e.g. on top of the exhaust pipe).

The driver can't really correct for this. All it knows is that the app is requesting the Z-buffer to be downsized into a texture measuring 840x525 (quarter res of 1680x1050), and then used as the Z-buffer. It requires a lot of effort to not only detect this and make an AA'd buffer behind the application's back, but also trying to put correct values in each sample.

Damn RSX and it's wimpy alpha fillrate...

 

[Skinner]

I hope they take care off the blurry SSAA asap, hopefully with the next cats.

 

[swaaye]

Has ATI worked DX10+ SSAA in or is it still DX9 or lower only?