The TRUTH about SSAA

[Jig McGalliger]

There is a LOT of misconception about SSAA, so here is the truth.

Speaking in terms of FHD or 1920x1080, that is 2,073,600 pixels, 2x SSAA doubles your internal rendering resolution. Meaning the total number of pixels, not double both dimensions; therefore, 2x SSAA gives 4,147,200 pixels, break that down into a 16:9 multiplicative ratio and you get 2715x1527. While 4x SSAA gives 8,294,400 pixels, 8 million pixels is not 8k resolution (so no one gets antzy here!) which is 3840x2160 internal rendering resolution. This is not additive or exponential, it is multiplicative then applied to a ratio.

This excerpt is straight from Nvidia and 4A:

"By default, Metro: Last Light utilizes 4A’s proprietary Analytical Anti-Aliasing (AAA) to lessen the impact of jagged, aliased edges on geometry, objects, characters, transparent textures, and all other screen elements. A combination of FXAA and 4A tech, AAA improves upon other post-processing anti-aliasing techniques by doubling the internal resolution of the picture using pattern and shape detection, and downsampling the post-processed result back to the user’s screen resolution, resulting in an anti-aliased image that is far smoother and clearer than traditional post-process techniques can create.

In Metro 2033, players could utilize Multisample Anti-Aliasing (MSAA) instead of Analytical Anti-Aliasing to generate an even sharper, less aliased image. Unfortunately, due to 2033’s deferred lighting, the performance impact of MSAA was tremendous, making its use unfeasible on anything other than a three or four multi-GPU system when every other setting was enabled and maxed out. For Last Light, 4A has replaced Multisample Anti-Aliasing with Supersampling Anti-Aliasing (SSAA), which creates a significantly smoother, more detailed image by internally rendering every element of the screen at a higher resolution. In other words, on a player's 1920x1080 monitor, 2X SSAA renders Last Light at 2688x1512 on the GPU before resizing the image to 1920x1080, increasing the amount of detail per pixel. At 3X SSAA the downsample resolution increases to 3264x1836, and at 4X SSAA it is 3840x2160, the resolution of next-gen “4K” monitors and screens.

To ensure maximum anti-aliasing quality, 4A continue to use AAA even when SSAA is enabled, simultaneously drawing on the strengths of both techniques. And because SSAA supersamples everything, AAA is also supersampled, doubling in quality when 4X SSAA is enabled."

http://www.geforce.com/whats-new/guides/metro-last-light-graphics-breakdown-and-performance-guide#last-light-anti-aliasing

Interesting note about development of 4A's Anti Aliasing, the engineers are pretty smart. They opposed FXAA (which they rewrote for AAA) and TXAA (both Nvidia tech) because they think AA should be the job of the programmers and not some magic one-all by the drivers. On a fully deferred rendering system (all Metro games) 2x SSAA runs more efficient and looks better than 4x MSAA. These are some of the same engineers that made the X-ray engine for all the Stalker games, they left when GSC wouldn't give interest in their new engine ideas.

[-BMF-]

Was worth the read.

[Jewva]

+1

[GAmbrose]

Thanks, that clarifies what I told somebody else that 4xSSAA @ 1080p was 'only' 4k.

They said I was wrong.

[D-M4L1C3]

i m using 4k thats why i m not using any ssaa ^^ but its nice that some devs using ssaa (croteam, ...)

[Death Metal Koro]

If your computer can handle it, SSAA will make your game so much more beautiful...too bad it kills most computers..

[FrosTytheNoob]

Originally posted by Jig McGalliger:

There is a LOT of misconception about SSAA, so here is the truth.

Speaking in terms of FHD or 1920x1080, that is 2,073,600 pixels, 2x SSAA doubles your internal rendering resolution. Meaning the total number of pixels, not double both dimensions; therefore, 2x SSAA gives 4,147,200 pixels, break that down into a 16:9 multiplicative ratio and you get 2688x1512. While 4x SSAA gives 8,294,400 pixels, 8 million pixels is not 8k resolution (so no one gets antzy here!) which is 3840x2160 internal rendering resolution. This is not additive or exponential, it is multiplicative then applied to a ratio.

This excerpt is straight from Nvidia and 4A:

"By default, Metro: Last Light utilizes 4A’s proprietary Analytical Anti-Aliasing (AAA) to lessen the impact of jagged, aliased edges on geometry, objects, characters, transparent textures, and all other screen elements. A combination of FXAA and 4A tech, AAA improves upon other post-processing anti-aliasing techniques by doubling the internal resolution of the picture using pattern and shape detection, and downsampling the post-processed result back to the user’s screen resolution, resulting in an anti-aliased image that is far smoother and clearer than traditional post-process techniques can create.

In Metro 2033, players could utilize Multisample Anti-Aliasing (MSAA) instead of Analytical Anti-Aliasing to generate an even sharper, less aliased image. Unfortunately, due to 2033’s deferred lighting, the performance impact of MSAA was tremendous, making its use unfeasible on anything other than a three or four multi-GPU system when every other setting was enabled and maxed out. For Last Light, 4A has replaced Multisample Anti-Aliasing with Supersampling Anti-Aliasing (SSAA), which creates a significantly smoother, more detailed image by internally rendering every element of the screen at a higher resolution. In other words, on a player's 1920x1080 monitor, 2X SSAA renders Last Light at 2688x1512 on the GPU before resizing the image to 1920x1080, increasing the amount of detail per pixel. At 3X SSAA the downsample resolution increases to 3264x1836, and at 4X SSAA it is 3840x2160, the resolution of next-gen “4K” monitors and screens.

To ensure maximum anti-aliasing quality, 4A continue to use AAA even when SSAA is enabled, simultaneously drawing on the strengths of both techniques. And because SSAA supersamples everything, AAA is also supersampled, doubling in quality when 4X SSAA is enabled."

http://www.geforce.com/whats-new/guides/metro-last-light-graphics-breakdown-and-performance-guide#last-light-anti-aliasing

Interesting note about development of 4A's Anti Aliasing development, the engineers are pretty smart. They opposed FXAA (which they rewrote for AAA) and TXAA (both Nvidia tech) because they think AA should be the job of the programmers and not some magic one-all by the drivers. On a fully deferred rendering system (all Metro games) 2x SSAA runs more efficient and looks better than 4x MSAA. These are some of the same engineers that made the X-ray engine for all the Stalker games, they left when GSC wouldn't give interest in their new engine ideas.

What I hate about METRO is that it does not give you the option to disable thier built-in AAA. I'd rather play with jaggies with full HD textures than haveto deal with SSAA

[Cuddle Bunny!]

If people don't know this type of stuff they should stick with consoles or do a lot of homework on pc settings and what the settings do

[Jig McGalliger]

Originally posted by FrosTytheNoob:

snip

Why would you disable a great AA method? AAA actually doesn't filter out the texture quality like FXAA does. All of the 4 Metro games have used AAA at all times.

[FrosTytheNoob]

Originally posted by Jig McGalliger:

Originally posted by FrosTytheNoob:

snip

Why would you disable a great AA method? AAA actually doesn't filter out the texture quality like FXAA does. All of the 4 Metro games have used AAA at all times.

the default AAA of metro still uses FXAA it still a little bit blurs out textures I can notice it compared when I activate SSAA which basically doubles the pixels which makes it ultra clear but at a cost of half of your fps.

Any game using FXAA should be abandoned to be honest FXAA is the worst AA out there

[Jig McGalliger]

AAA is not the same as FXAA, nor does it "use" FXAA. SSAA does NOT disable AAA, so you are still seeing AAA when you turn on SSAA. You clearly didn't read the the post.

[trek554]

Originally posted by Jig McGalliger:

AAA is not the same as FXAA, nor does it "use" FXAA. SSAA does NOT disable AAA, so you are still seeing AAA when you turn on SSAA. You clearly didn't read the the post.

actually AAA does use some FXAA. remember search first before arguing...lol

http://www.geforce.com/whats-new/guides/metro-last-light-graphics-breakdown-and-performance-guide

"A combination of FXAA and 4A tech, AAA improves upon other post-processing anti-aliasing techniques by doubling the internal resolution of the picture using pattern and shape detection, and downsampling the post-processed result back to the user’s screen resolution, resulting in an anti-aliased image that is far smoother and clearer than traditional post-process techniques can create."

blurriness can range wildly depending on what level and type of FXAA is used and in this game I dont think it negatively impacts the image at all though like he is claiming.

[Jig McGalliger]

Again, it doesn't "use" FXAA. That is like saying a Mac is just a Linux PC (is is, but it is heavily rewritten from the kernel up). AAA is heavily rewritten to do what FXAA does in a different manner, namely with shape detection. The only blurring it does it around the edges of objects (where you want it), instead of the scene as a whole like FXAA. Any texture degradation on screen is happening only in places where you can't even see more than a few pixels of that texture. Multisampling does this too. I know the article, I'm the OP.

[trek554]

Originally posted by Jig McGalliger:

Again, it doesn't "use" FXAA. That is like saying a Mac is just a Linux PC (is is, but it is heavily rewritten from the kernel up). AAA is heavily rewritten to do what FXAA does in a different manner, namely with shape detection. The only blurring it does it around the edges of objects (where you want it), instead of the scene as a whole like FXAA. Any texture degradation on screen is happening only in places where you can't even see more than a few pixels of that texture. Multisampling does this too. I know the article, I'm the OP.

ok then argue with yourself as it flat out says that it is a combination of FXAA and 4A tech.

[Jig McGalliger]

Yes, making it not FXAA at all. Here is how it works, they analyze what this certain technique does (FXAA) then they see how that technique works. Then they find ways to get around it's limitations and how they can do what said certain technique does in a DIFFERENT way. Nearly anything that resembles FXAA has been stripped out. You can read more about it on digital foundry.

[trek554]

Originally posted by Jig McGalliger:

Yes, making it not FXAA at all. Here is how it works, they analyze what this certain technique does (FXAA) then they see how that technique works. Then they find ways to get around it's limitations and how they can do what said certain technique does in a DIFFERENT way. Nearly anything that resembles FXAA has been stripped out. You can read more about it on digital foundry.

so then it still contains some FXAA elements. lol using your logic there is no side effects to alcohol in my drink since I mixed it with a Coke...