Antialiasing question

[Kamikaze_Ice]

I didn't want to bump THIS THREAD from 2013, so I'm making this one.
What kind of SSAA does Dolphin use for each backend? Ordered, rotated, sparse, other grid?

I'm feeling a bit stupid at the moment, so I've probbably found my answer and didn't even realize it.
Basically I'm wanting to use SGSSAA and not the other types, if possible.

I've already tried forcing SGSSAA via Nvidia Inspector, but none of the compatibility flag bits I've tried have worked (DX11). OpenGL does not like being told what to do either.
So to continue the thread from 2013, are there any known compatibility flag bits for forcing AA via driver for DX9/DX11/DX12 and OpenGL?

I feel stupid for having to ask this, I'm sure what kind of AA being used is documented somewhere (manual, official website, wiki, tooltip, help).... right?

[degasus]

You'll get ordered grid if you just choose the double IR, else we don't have any configuration how to set the GRID, so if you just select SSAA, the grid will be choosen by the driver. But bad luck, the driver AA options are usually only for the default framebuffer, not for offscreen rendering. We render everything offscreen, so I don't know a way to configure it.

[Kamikaze_Ice]

Forgive me, I'm posting this right after work. And it's been one of those days where I have too much blood in my caffeine system.

(01-26-2016, 06:55 PM)degasus Wrote: You'll get ordered grid if you just choose the double IR,...

How should I interpret this statement?
A) 2x internal resolution (1280x1056), alone, triggers OGSSAA?  I really don't think this is what you're saying, but someone else could take it as such.
B) 2x internal resolution (1280x1056), when used with SSAA option, does OGSSAA.
C) SSAA, when enabled on all internal resolutions greater than or equal to 2x internal resolution (1280x1056) will have an ordered grid sampling pattern.
Can you please clarify? Thanks.

(01-26-2016, 06:55 PM)degasus Wrote: ... else we don't have any configuration how to set the GRID, so if you just select SSAA, the grid will be choosen by the driver. ...

Does that mean we can "force" the sampling patterns by defining them in the driver ala Nvidia Inspector. What I mean is, define the supersampling option, but leave actual AA method as "application enabled" aka default?

(01-26-2016, 06:55 PM)degasus Wrote: ... But bad luck, the driver AA options are usually only for the default framebuffer, not for offscreen rendering. We render everything offscreen, so I don't know a way to configure it.

Ok, now by this statement I'm interpreting that your whole message was entirely about forcing any and all AA options via drivers ala Nvidia Inspector.
So now let's see if I get this.  "SSAA@2xIR=OGSSAA" and "SSAA@all other resolutions=driver default", but the driver default is basically an "unknown" (read: possibly different between drivers and/or video cards).

Forgive me degasus if I'm getting your message/intent bass ackwards (more like completely wrong, lol). Caffeine... hell of a drug.

I'm really trying to search for answers before asking questions and bothering other people, but things have "changed" since version 3.0, which is what the majority of my search results. And when everyone, including developers, is recommending development builds over the "stable" builds, I have a tendency to just ignore this "outdated" information.

In some other threads, I've seen statements, to paraphrase, that no one a handfull of people wanted a few more/better options.
I'll join thems minority peoples in the party/pantry/closet/room/cage under the stairs (read: requesting a "sparse grid" toggle/checkbox/option when using MSAA).



And one last question. Hypothetically speaking let's say we could force working AA via driver ala Nvidia Inspector. Would Dolphin's screenshot feature capture any AA forced this way? I know some PC games can do this, and some that can't, and I know Dolphin does not work the same way.
Actually, I think I just answered my own question; answer=no.

[AnyOldName3]

If you increase the game's internal resolution, then it still takes samples from the centre of each pixel. These pixels are in an ordered grid relative to the game's default pixels, so if you then play on a tiny monitor so the extra pixels from the increased IR need to be averaged together (or you play on a normal monitor with the IR set higher than your display resolution) that'll give the effect of OGSSAA. Think of it like Dynamic Super Resolution - you force the game to render to a higher resolution virtual screen and then filter it back down.

Dolphin's AA settings work within the high-IR pixels, and use whichever sampling mode the driver decides is appropriate. The implication of this is that there are two stages at which Dolphin can take multiple samples for one pixel in the original game, and there are therefore two stages at which multiple samples will be blurred together if the screen can't display them.

[Kamikaze_Ice]

Not trying to be snide here, but thanks for telling me something I already know (first paragraph), AnyOldName3. I am grateful for both you and degasus for taking time out of your day to reply to my inquiries.

I made my second post because degasus confused me with how his reply was written, which I broke into segments and tried to explain my interpretation. I know I'm terrible at putting my thoughts into words in a way that others can understand.

Here is the first confusion:

(01-26-2016, 06:55 PM)degasus Wrote: You'll get ordered grid if you just choose the double IR,...

If I was to have absolutely know idea about anything about antialiasing beyond "AA=no jaggies", and was to read this, I would assume degasus was being quite literal: only 2x internal resolution = ordered grid AA, and put the AA option to none (instead of MSAA or SSAA).
I don't think that the intent of degasus, I just wanted to point it out if someone else in the future was to arrive at this thread from searching.

Second confusion:

(01-26-2016, 06:55 PM)degasus Wrote: ... else we don't have any configuration how to set the GRID, so if you just select SSAA, the grid will be choosen by the driver. ...

Ignoring my first confusion, I read this as saying we can force the SSAA sampling pattern via driver ala Nvidia Inspector, and only the pattern (leaving the AA method as application-controlled, and not "enhancing" or "overriding" the app's AA method, but only defining the supersampling option as ordered/sparse/rotated grid types of supersampling).

Final confusion:

(01-26-2016, 06:55 PM)degasus Wrote: ... But bad luck, the driver AA options are usually only for the default framebuffer, not for offscreen rendering. We render everything offscreen, so I don't know a way to configure it.

The wording of this, to me, implies that the context was about "forcing" AA via the driver ala Nvidia Inspector, but "forced" AA would only apply to the default framebuffer, which Dolphin does not use due to offscreen rendering.


Now with your post, AnyOldName3, you say the driver decides what is appropriate. How does this work, why does it opt to use one method over another?
Why does 2x internal resolution implement ordered grid? Is it ONLY 2x internal resolution, or DOUBLES of Internal resolution (i.e. 2/4/8/16x Internal resolution and not 1.5/2.5/3/5/6/7x Internal Resolution).

Again, I do understand the various types of AA well enough (not at NaturalViolence's technical level). I found Dolphin's description of "SSAA" to be very... vague. Vague, only because there are different types of "SSAA" (aka ordered, rotated and sparse grids, each having their own pro/cons--covered in past threads on this forum; not trying to bring up another discussion about them).

From reading the 2013 thread, and others, it seems possible to add other grid sampling patterns (rotated and sparse grid), so could this be considered as a low priority feature request? Those threads seem to imply that only a few people has requested options like this, and I think it's because if it's not explicitly given as an option menu (which is VERY few games), the majority of gamers don't even know other options are availible. And the majority of those who DO know, know it's typically required that we need to FORCE it in the driver, and if it doesn't work then hope guru3d has found a working compatibility flag. At the end of the day, few people think to ask for the option under the assumption that it can't work period otherwise they could have forced it to work.


And again, I do have another question.
When are shaders added to the frames? I.e. would FXAA be applied to the Internal Resolution BEFORE it get's downsampled to my chosen screen resolution?
...And this might sound stupid, but has anyone tried double downsampling? Sure it's illogical, but "/shrug why not? 'Cause I can!"
I do find it interesting... high Internal Resolution downsampled by dolphin to a resolution greater than my native display, then using display (ala Nvidia "DSR" feature) to downsample the final image from Dolphin to my screen resolution).



Also, I wanted to share this.
Durante (of Dark Souls/Deadly Premonition and GeDoSaTo fame) made a little utility to easily and quickly compare various AA methods and how well they remove the various types of aliasing (like temporal/motion/shader/scaling/edge).
http://blog.metaclassofnil.com/?p=444 - A link to his blog with said tool.