DX11 MSAA

[Gabbyjay]

Yo,

one thing i always wondered about is the "quality levels" of Dolphin's MSAA in the DX11-plugin.

What exactly do these quality levels mean? I searched and googled all over but could not find any documentation.

If i turn on, for example, 4 samples (quality level 16), then what do i get?

4 samples is 4xMSAA, so what is added with the quality levels? Is it some kind of coverage sampling, so i get 4 color + 16 additional coverage samples in this case?



This is important as i enhance Dolphin's MSAA with SGSSAA, where its best to match the number of color samples to get the best image quality.

[xemnas]

I used to ask this question before but no accurate answer. How do you enhance MSAA with SGSSAA?

[Gabbyjay]

I enhance it with nvidia inspector, dont know about AMD cards.

SGSSAA uses MSAA's subpixel mask, so a higher SGSSAA-factor than MSAA-factor wont work, obviously.

If you use a higher MSAA-factor than SGSSAA-factor (8x MSAA with 4xSGSSAA, for example), the results are subotpimal, as SGSSAA won't get the ideal sample positions (it will just take the inner subpixels, according to nvidia).


So an explanation on how Dolphin's MSAA works would be great.

[neobrain]

It's up to the driver. There's no specific meaning for what "quality levels" are supposed to be, it's bscly just an internal index for gpu drivers to chose between their internal MSAA algorithms.

[Gabbyjay]

So what do nvidia drivers, for example, make out of it?

I dont even see a difference quality-wise, or in fps.

[neobrain]

I have no idea.

[xemnas]

(10-02-2013, 05:27 AM)Gabbyjay Wrote: I enhance it with nvidia inspector, dont know about AMD cards.

Thanks for the information. I'm using an AMD card. When I played Super Mario Sunshine, I got better result from MSAA 4x than MSAA 4x quality level 16.

[Gabbyjay]

Have you tried setting a MSAA-level in Dolpin an then turning on SSAA in Radeon's drivers?

Let me know if it works.

Playing in 3840x2160 at 8xSGSSAA with 16xAF definitely does a nice job on textures.

[NaturalViolence]

Gabbyjay Wrote:I enhance it with nvidia inspector, dont know about AMD cards.

AMD drivers don't support SGSSAA. They have RGSSAA.

Nobody knows what the quality levels do except nvidia/AMD. And they haven't said anything about them yet.

[Gabbyjay]

AFAIK AMD drivers support SGSSAA too.

4xSGSSAA, for example, essentially is RGSSAA, as you end up with a rotated grid for optimal EER. It's only scaled a bit, so you wont get vast subpixel-free areas between to neighbouring pixels. A rotated grid is a form of sparse grid in this case.

You can also see this on nVidia cards, when you have a look at the sample mask patterns for MSAA/SGSSAA:
http://pics.computerbase.de/1/5/8/8/6/41.png