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Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

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Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#51

Post by mananaysiempre »

Geee wrote: post #30
overgard wrote: post #7

I agree with his overall point, but I would point out: realism is not usually the point, the point is to look good. The problem with realism is once you get past "wow the computer can do that now", it's not very interesting -- most of reality is pretty dull looking!

I don't think this is true at all. I've been experimenting with a physical sky / atmosphere modeling, and it really seems that the most physically accurate sky is the most beautiful. I think this applies more generally to all light and shadows, and all natural effects which people perceive as beautiful, and at the same time difficult / expensive to recreate on a computer.

I recall a GDC presentation about a physically-based atmospheric model developed for a (good) AAA game released sometime in the last decade, and it reportedly took up a noticeable part of the frame budget, so evidently you’re not alone in this opinion.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#52

Post by mananaysiempre »

mrandish wrote: post #41
aaroninsf wrote: post #35

Earlier quoted context omitted.

I would suggest that both are true! It's common for games to have an intentional designed aesthetic which uses cultural and social and graphical "languages" to create specific emotional impacts and effects. The lower the budget the more this is leaned into for expedient reasons but that in turn creates genre expectations! Low-poly and 8-bit are fine examples of what were once a product of technical limitations becomi…

> It's common for games to have an intentional designed aesthetic ... to create specific emotional impacts and effects. And before games this was true of movies and before that photos and paintings. A master cinematographer can spend hours lighting a shot that will later be praised for its 'gritty realism' :-).

Yup. I once came across a (picture of a) test print made by one of the old black-and-white street photography greats, and it was all marked up with development adjustments for better lighting, contrast, and subject separation. Those were always a photographer’s main concern.

I think a Horizon Zero Dawn developer characterized their approach as “more realistic than reality” or something along those lines, i.e. they were aiming for the kind of perfect saturated look that you would only get in that golden hour with ideal surroundings but that we all recognize as real and at the same time don’t find too dull to stare at for hours. And I think for daytime HZD did do that quite well.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#53

Post by Terr_ »

dcrazy wrote: post #20
wincy wrote: post #12

Earlier quoted context omitted.

I think there’s a value in realism, ARC Raiders is one of my favorite games right now and it reminds of of movies like Stalker or The Shape of Water, movies that show old run down buildings and industrial complexes in their full glory, paint flaking, water in the wrong place, it’s just fantastic. It really sells me on being in a once busy space that’s been abandoned and fallen from its former glory.

I’m not on the ARC Raiders art team, nor have I even played the game. But I can say with some confidence that what people react to in computer graphics isn’t realism per se, it’s verisimilitude .

Right, too many games pitch the "realism" of "really like a Hollywood movie", reproducing effects which are really telltale flaws in cameras, microphones, or the theater-experience.

This is in contrast to the realism of "if you were there in person". If you step outside and look towards the sun and see lens-flares, consult an eye-doctor. If you see polyhedral lens-flares or bokeh... consult a roboticist.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#54

Post by hackrmn »

overgard wrote: post #7

I agree with his overall point, but I would point out: realism is not usually the point, the point is to look good. The problem with realism is once you get past "wow the computer can do that now", it's not very interesting -- most of reality is pretty dull looking!

I don't know, I was very happy when I discovered what Radiance can do with what you give it. I hear people get very good looking rendering with Blender, but my brain doesn't work like that (anymore?). Point being that not everything is about games and looking good, we need reliable tools to render synthetic scenes to assess a lot of non-game related things, like quality of lighting in architecture before erecting a skyscraper or buying a house etc. To that end, every bit of knowledge like the author seems be focused on, helps. I absolutely relate to the problem with "faking" things. Even developers of Unreal engine had acknowledged -- all too late, as it is -- that it's _light_ that most affects our perception of "realism". That and materials, which is why they had some sort of field trip to Iceland taking raw photos of rocks they could add to their materials library.

Another problem with looking good is that it's a) subjective (since it has no real or objective reference point, really) and b) it quickly goes stale once something else looks "better". Just look at Doom. It looked good in 1993, everyone would agree on that. It's not realistic, never was realistic and will certainly never be realistic unless you take a particular cocktail of drugs, I guess.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#55

Post by gmueckl »

ambicapter wrote: post #43
Geee wrote: post #30

Earlier quoted context omitted.

I don't think this is true at all. I've been experimenting with a physical sky / atmosphere modeling, and it really seems that the most physically accurate sky is the most beautiful. I think this applies more generally to all light and shadows, and all natural effects which people perceive as beautiful, and at the same time difficult / expensive to recreate on a computer.

> I think this applies more generally I would say the sky and a private eye's dimly lit, smoke-filled 1920s office are pretty different, actually.

While the resulting looks and aesthetics are very different, the same physical model for light scattering can be used to describe both. Any approximations of that are a concession to available computer performance.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#56

Post by Maken »

mfro wrote: post #2

SSAO really is awful but it’s the best performing AO we could get for a long time afaik. It’s such a hallmark of 00s and 10s rendering that I laugh every time I see it in a modern release. There are some new solutions hitting the space, I believe RTGI/PT inherently handles AO, and there is even a new method called ‘FidelityFX CACAO’ which does look considerably more realistic. Things are improving… slowly.

AO is an approximation of how indirect light behaves. If you have an actual global illumination solution you don't need these tricks.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#57

Post by Maken »

ivanjermakov wrote: post #25

Ambient occlusion is not only about realistic indirect lighting, but also about giving objects more depth. Great example here: https://developer.playcanvas.com/user-manual/graphics/lighti... Also, looking just at inner corners of the room is too specific, SSAO affects creases everywhere, not just at the inner corners of the box.

These examples mention explicitely ambient light, which is the point of the article. SSAO makes no sense for direct ligth.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#58

Post by gmueckl »

mrandish wrote: post #41
aaroninsf wrote: post #35

Earlier quoted context omitted.

I would suggest that both are true! It's common for games to have an intentional designed aesthetic which uses cultural and social and graphical "languages" to create specific emotional impacts and effects. The lower the budget the more this is leaned into for expedient reasons but that in turn creates genre expectations! Low-poly and 8-bit are fine examples of what were once a product of technical limitations becomi…

> It's common for games to have an intentional designed aesthetic ... to create specific emotional impacts and effects. And before games this was true of movies and before that photos and paintings. A master cinematographer can spend hours lighting a shot that will later be praised for its 'gritty realism' :-).

One theme that is common to almost all visual art that strives for some form of realistic appearance is that they start out with real material appearances and physical lighting behavior. Both are inescapable parts of the reality in our physical world, anyway.

By extension, this means that it is highly desirable to have a renderer capable of reproducing the real world as a baseline for highly controllable aesthetic tweaks. When you look especially at VFX specific tools, they have - almost without exception - two layers of tools: the first creates a realistic simulation (e.g. water/fire/shattering...) and the second layer allows for tweaks to control the final look.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#59

Post by gmueckl »

Maken wrote: post #56
mfro wrote: post #2

SSAO really is awful but it’s the best performing AO we could get for a long time afaik. It’s such a hallmark of 00s and 10s rendering that I laugh every time I see it in a modern release. There are some new solutions hitting the space, I believe RTGI/PT inherently handles AO, and there is even a new method called ‘FidelityFX CACAO’ which does look considerably more realistic. Things are improving… slowly.

AO is an approximation of how indirect light behaves. If you have an actual global illumination solution you don't need these tricks.

AO is derived from full GI with some extremely crude approximations. Anything that simulates full GI more accurately is implicitly a more physically accurate replacement of AO. Still, AO is not dead because it is still a rather simple and cheap cheat to add more visual definition to concave corners and highly shadowed areas. Sometimes, artists decide that their scene should have this extra touch.

Re: Corners Don't Look Like That: Regarding Screenspace Ambient Occlusion (2012)

#60

Post by groundzeros2015 »

Geee wrote: post #30
overgard wrote: post #7

I agree with his overall point, but I would point out: realism is not usually the point, the point is to look good. The problem with realism is once you get past "wow the computer can do that now", it's not very interesting -- most of reality is pretty dull looking!

I don't think this is true at all. I've been experimenting with a physical sky / atmosphere modeling, and it really seems that the most physically accurate sky is the most beautiful. I think this applies more generally to all light and shadows, and all natural effects which people perceive as beautiful, and at the same time difficult / expensive to recreate on a computer.

Modern games struggle with readability which is why there is a trend to paint interactive objects yellow. So arguably the realistic visuals are interfering with the purpose of the game.
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