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At 4K does AA become unneeded?

bomblord1

Banned
When you say "4k IR" then do you mean 4k internal resolution? because then it's rendering at 4k. With 2xAA.

Inany case, there's pretty obvious aliasing on the sword tips and at the first bright horizontal line from the top center.

What on earth are you talking about. I actually moved this picture to my 42" TV and got about 5" from it to be sure and there is not any aliasing on that. I think what you are seeing is the low poly geometry. Hold on I'll find a better picture it was my fault for choosing a poor example.
 

Seanspeed

Banned
What on earth are you talking about. I actually moved this picture to my 42" TV and got about 5" from it to be sure and there is not any aliasing on that. I think what you are seeing is the low poly geometry. Hold on I'll find a better picture it was my fault for choosing a poor example.
You don't get to pick better examples until you find one that satisfies your theory. You should be able to bring up any screenshots of any game at any moment, and if you can see aliasing in any of them, then you're wrong man.
 

Durante

Member
What on earth are you talking about. I actually moved this picture to my 42" TV and got about 5" from it to be sure and there is not any aliasing on that. I think what you are seeing is the low poly geometry. Hold on I'll find a better picture it was my fault for choosing a poor example.
First answer the question of whether you are using 4k internal resolution.

Because then what you are posting is a downsampled (to 1080p) 4k image with 2xAA.

So a 1080p image with 4xSSAA and 2xMSAA on top of that.

(And actually, that's a very low-contrast game overall, which inherently makes aliasing issues less pronounced)

Oh, and I am quite capable of distinguishing low-poly rendering from aliasing :p
 
I don't mind a little bit of aliasing, so at 1440p AA is the last thing i ever enable. Of course high resolutions are harder to drive as it is, so I'd take the performance jump every time over AA.

I imagine if I got a 4K screen I'd hardly ever use AA and wouldn't really mind, but it would still be noticeable, yeah.

Considering that an 8K 27 inch monitor would have a similar pixel density to the iPhone 5, and aliasing is still slightly noticeable on that device, we'd probably need something like 400 PPI, so like 10K or something.
 

shandy706

Member
I sit so far away, 12' from my 1080p set, that 4k looks like a movie, lol.

I can play a lot of games at 4k with my 980 now and I just turn off AA.


(although I still prefer a lower internal render with some AA for performance reasons)
 

Coconut

Banned
No.

As for when it becomes completely unnecessary, probably around 32k resolution per eye for a full FoV. 8k could be enough for a typical screen FoV, though it probably wouldn't eliminate shimmering completely.

Does AA help with textures?
 

bomblord1

Banned
First answer the question of whether you are using 4k internal resolution.

Because then what you are posting is a downsampled (to 1080p) 4k image with 2xAA.

So a 1080p image with 4xSSAA and 2xMSAA on top of that.

(And actually, that's a very low-contrast game overall, which inherently makes aliasing issues less pronounced)

Yes.

His original example said that AA is needed even when downsampling from 5K (also its 4X IR not 4K ir that's a typo 4x 480p) It's a ~2k image being rendered to a 1080p window with 2X AA.
 

Peterpan

Member
Shouldn't it be at what PPI level is AA not needed? Serious question. It doesn't help if your tv is 4k but it's massive.
 

Durante

Member
Does AA help with textures?
Help what? And which type of AA?

MSAA doesn't change textures at all.
SSAA improves perceived texture detail and reduces texture aliasing.
FXAA also may reduce texture aliasing, but at the cost of some blurring.
 

-griffy-

Banned
Super sampling is Anti-Aliasing. It's the best kind of AA as well.

I know what it is, I described what it is in the post you responded to.

I also edited that post to add:
If we were to take your method for eliminating aliasing at 1080p and apply it to a 4K screen resolution, it seems we would be rendering at 8K, with 2xSSAA applied over the top of that to effectively be needing the power to run at a resolution of 16k or so. That's just not feasible as far as hardware at this point, and not a realistic way to deduce that AA at 4K is not needed.
 

Durante

Member
Shouldn't it be at what PPI level is AA not needed? Serious question. It doesn't help if your tv is 4k but it's massive.
As I said earlier in the thread, what it really should be is pixels per degree of the field of view.

PPDFOV if you will.
 

Seanspeed

Banned
Yes.

His original example said that AA is needed even when downsampling from 5K (also its 4X IR not 4K ir that's a typo 4x 480p) It's a ~2k image being rendered to a 1080p window with 2X AA.
Stop saying 2xAA. Saying what type of AA, cuz its becoming confusing what you're talking about.

Also '2k' isn't any one thing. It could mean one of several different resolutions.

Be clear when talking about this stuff so we're all on the same page.
 

bomblord1

Banned
You don't get to pick better examples until you find one that satisfies your theory. You should be able to bring up any screenshots of any game at any moment, and if you can see aliasing in any of them, then you're wrong man.

I'm saying you are perceiving aliasing where there is none the sprites and textures are being blow up from 480p (this is a wii game) to 1080p that's where the effect is coming from.

I just grabbed a random screenshot of a game I took in dolphin (I know the settings I took it in) because I remembered it being incredibly crisp without inspecting it well enough (low res textures and sprites causing issues). the actual geometry in that picture has no visible aliasing in it. Look at the edge of the shoulders for example.
 

Seanspeed

Banned
Jaggies and aliased sprites aren't something that can be solved with any type of AA, and has nothing to do with resolution.

Anyway, Durante is all up in this
female dog
.
Well technically no, it cant be 'solved', but you *can* diminish jaggies to a degree that they become imperceptible depending on your viewing situation. And this is done through AA techniques and resolution. Obviously if get close/zoom in enough, you'll still be able to see the pixel steps of an object but there's no need to be so literal about it when we're talking about practical scenarios.
 

bomblord1

Banned
Stop saying 2xAA. Saying what type of AA, cuz its becoming confusing what you're talking about.

Also '2k' isn't any one thing. It could mean one of several different resolutions.

Be clear when talking about this stuff so we're all on the same page.

4x 480p exactly 2560 x 2112 with 2x AA running in dolphin.
 

Durante

Member
Stop saying 2xAA. Saying what type of AA, cuz its becoming confusing what you're talking about.

Also '2k' isn't any one thing. It could mean one of several different resolutions.

Be clear when talking about this stuff so we're all on the same page.
4x native in dolphin is 2560x2112. I believe they implement 2xSSAA one-dimensionally, so what we are seeing there is either 5120x2112 or 2560x4224 downsampled to 1080p. Combined with the overall low contrast, and the fact that it's just an image (eliminating temporal aliasing and flicker) it's not too surprising that there's little aliasing in that.
 

bomblord1

Banned
I know what it is, I described what it is in the post you responded to.

I also edited that post to add:
If we were to take your method for eliminating aliasing at 1080p and apply it to a 4K screen resolution, it seems we would be rendering at 8K, with 2xSSAA applied over the top of that to effectively be needing the power to run at a resolution of 16k or so. That's just not feasible as far as hardware at this point, and not a realistic way to deduce that AA at 4K is not needed.

I don't know if it's needed at 4K I just thought since I can't even see it on my 20" monitor while downsampling in dolphin to 1080p with 2xAA then a 4K monitor would probably be not needed. I've never seen a 20" 4K monitor in person. That initial "32K" resolution was what started this.
 

-griffy-

Banned
4x native in dolphin is 2560x2112. I believe they implement 2xSSAA one-dimensionally, so what we are seeing there is either 5120x2112 or 2560x4224 downsampled to 1080p. Combined with the overall low contrast, and the fact that it's just an image (eliminating temporal aliasing and flicker) it's not too surprising that there's little aliasing in that.

And it's therefore not really accurate to say "1080p with 2xAA has no noticeable aliasing on my 1080p monitor" when that is what you are actually talking about.
 

-SD-

Banned
Here's an example of those nasty moiré patterns mentioned earlier that SSAA helps reduce.

No AA ---> @_@
2014-09-29_12.44.43mii0t.png


8X SSAA to the rescue! (supersample antialiasing)
2014-09-29_12.45.50_sw9e6g.png
 

Coconut

Banned
Help what? And which type of AA?

MSAA doesn't change textures at all.
SSAA improves perceived texture detail and reduces texture aliasing.
FXAA also may reduce texture aliasing, but at the cost of some blurring.

the different functions kinda answers my questions. In my mind and mostly in the way I hear AA spoke of it usually seems to only be in regards to the edges of a model rather than what's going on inside of the model, if that makes sense.
 

Seanspeed

Banned
I'm saying you are perceiving aliasing where there is none the sprites and textures are being blow up from 480p (this is a wii game) to 1080p that's where the effect is coming from.

I just grabbed a random screenshot of a game I took in dolphin (I know the settings I took it in) because I remembered it being incredibly crisp without inspecting it well enough (low res textures and sprites causing issues). the actual geometry in that picture has no visible aliasing in it. Look at the edge of the shoulders for example.
You're not seeing the same things we are, since you're on a 20" monitor from 3ft away, obviously. There *is* aliasing in that screenshot.

You should probably get a larger monitor if you're sitting that far away, too. Must seem tiny.
 

bomblord1

Banned
And it's therefore not really accurate to say "1080p with 2xAA has no noticeable aliasing on my 1080p monitor" when that is what you are actually talking about.

You are right I was wrong on that I didn't actually check the rendering resolution until I started grabbing screenshots. It would be better to say 2560x2112 downsampled to 1080p with 2xAA
 

bomblord1

Banned
You're not seeing the same things we are, since you're on a 20" monitor from 3ft away, obviously. There *is* aliasing in that screenshot.

You should probably get a larger monitor if you're sitting that far away, too. Must seem tiny.

Just moved to my 42" TV still not seeing it.
 

shockdude

Member
You are right I was wrong on that I didn't actually check the rendering resolution until I started grabbing screenshots. It would be better to say 1080p with 4xSSAA (which is 4K right?)
No. 4xIR in Dolphin is 4x of 640x528 which is 2560x2112. 4K is 3840x2160.

To be fair 2560x2112 with 2xMSAA, while not perfect, is pretty decent.

As for the screenshot, I noticed aliasing in the right character's right leg; you can see a tiny little stairstep in front of the left guy's sword.
 

Mohonky

Member
Depends on the display tech also. I game on a plasma so the image is inherently softer. Bayonetta 2 got murdered when people discussed its graphics because of jaggies and honestly I saw fuck all jaggies when I played it. The only time I saw them was during cutscenes which looked oddly lower res for some reason and the jaggies were really obvious, in game though I barely even noticed any anyless there was an object that was prism shaped with hard sharp edges, thats when thats about the only time in game I noticed them, outside of that and the cutscenes I cant recall seeing fuck all.
 

Stallion Free

Cock Encumbered
On my 42 inch plasma and a proper distance? No. Post-process AA gets it damn close, but shader aliasing can still create issues.
 
Shouldn't that be measured in ppi/dpi?

My surface pro 2 has a 10" 1080p so that'd be 208 dpi, my 47" tv has just 47 dpi in comparison
 

tuxfool

Banned
Dolphin's solution they literally don't label it. Someone earlier said it's MSAA.

Now I want you to attempt similar comparisons with modern games, with more detailed geometry, Higher Dynamic Range and Greater Specular highlights.

Aliasing becomes a lot less visible when there isn't a great deal of contrast. In other words as in generic signal processing terms, you're trying to fit too much real information with too limited a capability to physically replicate.
 

borghe

Loves the Greater Toronto Area
graphics snobs say no... frankly on my PC I am fine with 1080p and no AA. every once in a while I will see a shimmer and think "oh hey..." but mostly I am fine with the higher performance and ultra settings.
 

Durante

Member
http://abload.de/img/so3ee9-3zcsef.png

Same settings ignore the hud and background shrubbery (they are flat textures no geometry) the hud is being rendered in 480p. I can notice slight aliasing here on the edges of characters specifically around the top of the girls hat 4XAA would probably fix that.
There's pretty obvious aliasing on high-contrast near-horizontal or near-vertical edges in that, e.g. between the tree and the sky.


Shouldn't that be measured in ppi/dpi?
No.
As I said earlier in the thread, what it really should be is pixels per degree of the field of view.

PPDFOV if you will.
 

Seanspeed

Banned
So not quite 4k.
About 3 million pixels short, actually.

I got close enough I could make out individual pixels and inspected the edges of all the characters to try to find the Aliasing.
Then you don't know what to look for.

http://abload.de/img/so3ee9-3zcsef.png

Same settings ignore the hud and background shrubbery (they are flat textures no geometry) the hud is being rendered in 480p. I can notice slight aliasing here on the edges of characters specifically around the top of the girls hat 4XAA would probably fix that.
Aliasing is aliasing man, however its caused. You cant just say, "Oh those jaggies don't count." There's aliasing all over that image. The grass, the walls, the tree trunk, the characters, the stone railing, etc.
 
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