Is ssaa 2x same as 2560x1440 ？

[AcidRains2016]

maybe i'm not saying very accurate, i mean, is ssaa 2x same as double native resolution?
I knew ssaa stands for supersampling, and by double resolution i mean something like dsr or self created downsampling, so i guess there must be something different, so anyone cares to explain the difference of perfomance cost, and image quality as well.

[yusupov]

good question. my guess would be SSAAx2 is better than just using default nvidia DSRx2 because its specifically optimized for the game. and DSR has a 'smoothing' setting that ive never bothered to understand. but yeah im curious what ppl think/know as well

[LexFreeman]

The goal is the same, but the process is pretty different.
You can notice the difference by looking at the HUD: with supersampling (AKA SSAA), its size doesn't change because the actual resolution doesn't change. SSAA 2x renders the image at twice the resolution along each axis, that is 4 pixels in the area of a single pixel, 4x at four times the resolution (so 16x pixels), and so on. Basically, let's say SSAA 2x renders 4 pixels in one.
On the other hand, with downsampling (so DSR/VSR), the game actually runs at a higher resolution and scales everthing else this way; that's why the HUD could look shrunk (but it actually depends on the game you are playing). Then, the graphics driver scales again the image to match the resolution of your monitor.

Performance-wise, SSAA has a greater impact because it does not compress/scale down the higher resolution. But it depends not only on the GPU, but also on the CPU, RAM and motherboard.
As far as the quality is concerned, you should always run DSR together with another AA technique, whether it is FXAA, SMAA, TXAA or SSAA.

About DSR's smoothness, I think it blurs the image a bit too much and I would set it as low as possible, the higher the DSR factor, the lower the smoothness, and then use the game native AA, like SSAA for example. But that's just a personal choice, you should play a bit with the settings and see what looks better for you.

Hope this answer your question!

[Tiranasta]

Originally posted by LexFreeman:

The goal is the same, but the process is pretty different.
You can notice the difference by looking at the HUD: with supersampling (AKA SSAA), its size doesn't change because the actual resolution doesn't change. SSAA 2x renders the image at twice the resolution along each axis, that is 4 pixels in the area of a single pixel, 4x at four times the resolution (so 16x pixels), and so on. Basically, let's say SSAA 2x renders 4 pixels in one.

2x SSAA only contains two times as many samples, not four. It's very similar to scaling the internal resolution by a factor sqrt(2) in each dimension, but the sparse grid sample pattern generally used for SSAA isn't exactly equivalent to any rectangular pixel grid (as neighbouring sample points are neither horizontally nor vertically aligned).

[AcidRains2016]

Originally posted by yusupov:

good question. my guess would be SSAAx2 is better than just using default nvidia DSRx2 because its specifically optimized for the game. .

yes,think about the same too, because judge from some game have it's own ssaa so maybe they got a nice optimization for it, i think i'm going to try it myself for the second playthrough,
and the smoothing settings via dsr i think it is gaussian filter from what i heard, adjusting it can somehow gets image blurrier or sharper, won't hurt to have an option for tweaking and tuning i guessed=)

Originally posted by LexFreeman:

The goal is the same, but the process is pretty different.
You can notice the difference by looking at the HUD: with supersampling (AKA SSAA), its size doesn't change because the actual resolution doesn't change. SSAA 2x renders the image at twice the resolution along each axis, that is 4 pixels in the area of a single pixel, 4x at four times the resolution (so 16x pixels), and so on. Basically, let's say SSAA 2x renders 4 pixels in one.
On the other hand, with downsampling (so DSR/VSR), the game actually runs at a higher resolution and scales everthing else this way; that's why the HUD could look shrunk (but it actually depends on the game you are playing). Then, the graphics driver scales again the image to match the resolution of your monitor.

Performance-wise, SSAA has a greater impact because it does not compress/scale down the higher resolution. But it depends not only on the GPU, but also on the CPU, RAM and motherboard.
As far as the quality is concerned, you should always run DSR together with another AA technique, whether it is FXAA, SMAA, TXAA or SSAA.

About DSR's smoothness, I think it blurs the image a bit too much and I would set it as low as possible, the higher the DSR factor, the lower the smoothness, and then use the game native AA, like SSAA for example. But that's just a personal choice, you should play a bit with the settings and see what looks better for you.

Hope this answer your question!

Thanks, very enlighten, nice explaination, this helps a lot=)

Originally posted by Tiranasta:

Originally posted by LexFreeman:

The goal is the same, but the process is pretty different.
2x SSAA only contains two times as many samples, not four. It's very similar to scaling the internal resolution by a factor sqrt(2) in each dimension, but the sparse grid sample pattern generally used for SSAA isn't exactly equivalent to any rectangular pixel grid (as neighbouring sample points are neither horizontally nor vertically aligned).

thank you, i'm curious about this sparse grid sample, any advantage or disvantage of it ?

[danman]

Originally posted by acidrains2016:

thank you, i'm curious about this sparse grid sample, any advantage or disvantage of it ?

It's more random than an ordered grid, so less prone to produce artifacts at certain angles of the geometry IIRC.