Anti Aliasing vs Internal Resolution

phenomenalkai · 06-17-2015, 07:29 AM #1

I'm curious as to what would be a better experience if you have the graphical power to use in Dolphin. For example playing on a 1080p screen, would it be better to increase IR to 6x with no AA or would it be better to play at 3x which is 1080p and increase the AA to like 8 samples (quality level 16)? I'm interested to know about this for the latest Dolphin build. Thank you for reading!

***MayImilae*** · 06-17-2015, 07:42 AM #2

Raising the internal resolution will be a poor substitute for anti-aliasing. Dolphin doesn't have a scaling filter for it's internal resolution system, so you can raise the internal resolution as high as you want, and aliasing will still appear! It's better to set the internal resolution to something that matches your system (3x native for 1080p for example) and then turn on SSAA.

Helios is working on a PR to tip users about this in the GUI. Apparently that is really needed!

**Helios** · (This post was last modified: 06-17-2015, 09:55 AM by Helios.)

Hi! I am in fact working on a warning for this. Unfortunately right now it's a really situational answer for what you're asking. what major says is entirely correct as far as I know. In your situation, it's ideal to set 3x and turn on the AA of your choice. However, with some games AA can KILL performance, so be mindful!

In the future we'll have a proper downsampling filter (I believe some people more capable than I are working on that), until then, when I figure this out we'll have a nice little warning in the settings dialog to warn you of suboptimal IR settings. Smile

EDIT: Dev team are actually pretty divided on this issue. I don't think a warning is going to happen. The better solution would be to implement a downsampling filter.

kirbypuff · (This post was last modified: 06-18-2015, 01:07 AM by kirbypuff.)

(06-17-2015, 07:29 AM)phenomenalkai Wrote: For example, on a 1080p screen, would it be better to increase IR to 6x with no AA or would it be better to set the IR to 3x which is 1080p and increase the AA to like 8 samples (quality level 16)?

I wouldn't recommend using any kind of standard AA (MSAA/CSAA/EQAA/MFAA), It's relatively low quality and introduces all kinds of issues.
8xMSAA is also a worse choice than 4xMSAA (anything higher than 4x is too blurry / a waste of GPU power).

For best image quality without any issues, set the IR to 3x and use SSAA.
SSAA is available only if you use the OpenGL backend.

NOTE: SSAA can be very demanding (when combined with a high IR), especially the '9x' setting.
3xIR + 4xSSAA is equivalent to 6xIR (you need a decent (upper mid-range) GPU for this).
3xIR + 9xSSAA is equivalent to 9xIR (you need a high-end GPU for this).

If you use the Direct3D backend (e.g. for better performance on AMD hardware), then the best option is to set the IR to 6x and turn off the standard AA. Direct3D doesn't have a SSAA option (yet), so 6xIR is recommended in this case.

**admin89** · 06-18-2015, 01:22 AM #5

IMO , FXAA is the best

kirbypuff · (This post was last modified: 06-18-2015, 02:05 AM by kirbypuff.)

(06-18-2015, 01:22 AM)admin89 Wrote: IMO , FXAA is the best

Downsampling / SSAA is better than any "poor man's AA" (post-processing AA shader).
Downsampling / SSAA, for example, adds more detail or sharpness in addition to smoothing out the jagged edges.

**admin89** · 06-18-2015, 01:46 AM #7

For Speed : FXAA > 4x MSAA > 8x MSAA > .... > 4xSSAA
For Quality : 4x SSAA > FXAA > 8xMSAA > 4x MSAA
SSAA is just too demanding , both MSAA and MFAA are too blurry
That's why FXAA is the best of both worlds.

***Shonumi*** · 06-18-2015, 01:49 AM #8

Eh, I've never had an issue with MSAA looking too blurry. I'm actually hard-pressed to notice a difference between 4x, 8x, and 16x when using a high IR. It probably makes a bigger difference on lower IRs (too lazy to test).

kirbypuff · (This post was last modified: 06-18-2015, 02:12 AM by kirbypuff.)

(06-18-2015, 01:46 AM)admin89 Wrote: That's why FXAA is the best of both worlds.

"Best of both worlds" would be a combination of slight downsampling (4xIR -> 1080p) and a post-proc AA shader (HQ FXAA or SMAA 1x)

phenomenalkai · 06-19-2015, 07:15 AM **#10**

(06-18-2015, 12:49 AM)kirbypuff Wrote:
(06-17-2015, 07:29 AM)phenomenalkai Wrote: For example, on a 1080p screen, would it be better to increase IR to 6x with no AA or would it be better to set the IR to 3x which is 1080p and increase the AA to like 8 samples (quality level 16)?

I wouldn't recommend using any kind of standard AA (MSAA/CSAA/EQAA/MFAA), It's relatively low quality and introduces all kinds of issues.
8xMSAA is also a worse choice than 4xMSAA (anything higher than 4x is too blurry / a waste of GPU power).

For best image quality without any issues, set the IR to 3x and use SSAA.
SSAA is available only if you use the OpenGL backend.

NOTE: SSAA can be very demanding (when combined with a high IR), especially the '9x' setting.
3xIR + 4xSSAA is equivalent to 6xIR (you need a decent (upper mid-range) GPU for this).
3xIR + 9xSSAA is equivalent to 9xIR (you need a high-end GPU for this).

If you use the Direct3D backend (e.g. for better performance on AMD hardware), then the best option is to set the IR to 6x and turn off the standard AA. Direct3D doesn't have a SSAA option (yet), so 6xIR is recommended in this case.

So for my R9 280. I should turn off AA and run the game at 6x resolution (effectively 4k according to GUI).
My CPU is an i5 4690k overclocked to 4.5 ghz btw.