Real Time GI idea for skyrim?

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Re: Real Time GI idea for skyrim?

Dude, you should trust my knowledge and experience a little bit more.
In case of reflections, they are useless, because only low lod drawed and not all the time. Game scene differs a lot from reflections.
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Re: Real Time GI idea for skyrim?

I never said I didn't trust your knowledge? I know that's its a low level lod. But it might still have some use. Idk where XD (pbr? probably not...)
but, idk I heard sonic talking about screen space GI. Idk if you could make the camera out put into a different shape then do the GI effect.
But I was just thinking as always.

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Re: Real Time GI idea for skyrim?

Skyrim Raytracing ENB Idea:


Basically you guys have said ray tracing in TES V Skyrim is not possible. Hear me out on this, but I think it might be and I hopeful can show how it might be.

So I was looking through rasterization and gpu techniques for path tracing (or raytracing) when I can appon this!
[youtube] https://www.youtube.com/watch?v=0yLrVZGNFlA [/youtube]
This proposes away to ray trace, or path trace a scene using only a buffer from 6 different views, or a cube map essentially. I know that skyrim's cube maps are in really low res lod (I’m not sure about special editions though). I realized that, if this is used for only a diffuse pass that it might be okay. As a diffuse reflection is not a perfect reflection, thus no one will knowest if it’s an lod or not.


The only problems with is:
a. How to get it on screen or back on objects without distortion, or a weird effect of stretching? (which might be easy to do).

b. An extension of the first problem but a different approach. Because this is cube map space how do I get it back on the screen without having to up directly the low level lod cube map on screen?


My solutions:
a. Some way of comparing the camera direction and pixels to the cube maps.


Here’s so more info:
http://graphics.cs.aueb.gr/graphics/doc ... 016-av.pdf

And code with extra demo link

http://graphics.cs.aueb.gr/graphics/dow ... ode-cr.zip

http://kostasvardis.com/files/research/ ... i3d2016.7z

I’m also not sure if some one here as already thought of this… So sorry for posting this if they have...

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Re: Real Time GI idea for skyrim?

Dude, i told you already, cubemap in skyrim is piece of shit. It's not drawed every frame, so while moving things go wrong. Objects drawed to it are not what you see on screen, it contain almost nothing and low lod landscape which have different color, different lighting and have huge difference by position from the high detailed version of it from the screen. Even as IBL map such texture can't be used, it's awful. Engine is prehistoric crap and B*da do not have good programmers who can change it to the better, dx11 version is a bit faster only because of lower draw calls costs compared to dx9, but game still draws many thousands of objects on screen. Draw them again 6 times to cubemap means decrease performance 6 times.
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Re: Real Time GI idea for skyrim?

Okay, because where taking the cube map and getting a bunch of depth maps from them just offset the points when I move. Again It shouldn't matter every frame or not because of diffuse. I could see a problem with npcs though.
Also, drawing them 6 times = worse perforce? Were talking about path tracing here correct? It will already be "bad performance", Also the people running this would need like gtx titans+ So< I doubt that would be an issue. In his video he uses a resolution of 400x400 for all other views. So, it would be like an extra view the size of 2000x2000 compared to 1080x1920 for each screen, or an extra view of 5400x9600.

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Re: Real Time GI idea for skyrim?

So, you asking for non realtime bruteforce gi without optimizations? Sorry, as programmer i'm not interested absolutely, there are other ways much more precise to implement it, if performance doesn't matter. And it's also doesn't matter diffuse colors or depth do you need in cubemaps, because depth is also differs from scene which you see on screen.
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Re: Real Time GI idea for skyrim?

Hi Boris, I thought of making a new topic for what I'm about to say, but I figured this thread would be a good enough place.

So, regarding real-time GI from sunlight, have you considered using reflective shadow maps? I've had quite good results using a custom variation based on directly sampling depth, flux/albedo, and normal buffers instead of using virtual point lights (so, "gathering" instead of "shooting"). My results have been quite good and fast enough to use in my own projects. Considering your skill and familiarity with stochastic/jittered sampling and filtering, as well as gathering screen-space data for SSIL, I'm sure you could come up with a fantastic result!

I'm not sure, but I'm guessing that with this kind of modding, you don't have the luxury of rendering custom shadow maps. From what I can see, I'd guess that you do at least have access to the sunlight shadowmap depth textures. If this is the case, you could construct a shadow-space normal texture from the shadow depth texture in a separate pass. I think that with these two textures, a decent result could be achieved, although bounced light would have to be an "assumed" color due to the lack of a flux/albedo texture, but I have an idea for that.

So, if you can't draw albedo textures during the sun shadow map render passes (or modify those passes at all), am I right in guessing that you're able to load texture assets from Skyrim's data files? Skyrim uses a set of color textures for rendering distant terrain (I think I spotted them when browsing through Skyrim's textures), right? Well, perhaps you can sample the color from these textures based on the position of the cell that the player is in as an approximate substitute for a proper flux/albedo buffer. That way, at least the bounced light would assume the color of nearby terrain.

Of course, all of this being possible rides on whether you have sunlight shadow depth buffer access. And hey, maybe you've already thought of all this, but I figured I'd share my thoughts just in case!

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Re: Real Time GI idea for skyrim?

I tried that, but only intensity without colors as i can't draw any extra geometry without huge performance impact. At first i thought about accumulating data from screen, kinda voxelisation, but when it comes to modified game which allow to switch weathers and increase time scale, accumulation result fails and looks buggy. Color of the sun as indirect light do not look well in many cases, much more important to have green reflection on body near grass, while just yellow or white isn't much noticable compared to ambient bottom color. In Dragon's Dogma that looked more or less okay, because game itself much worse, but in Skyrim with current ENBSeries such addon seems not worth the result (not many players even use ssao/ssil). Look at the legs, it's just pure luck that most of areas are sandy color:
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Re: Real Time GI idea for skyrim?

What about my idea of using the distant terrain LOD textures (the ones located in textures/terrain/tamriel inside Skyrim - Textures.bsa) as a source for indirect light color? Is that not possible? Sure, you wouldn't get specific object colors, but at least you'd get green for grassy regions, white for snowy, orangish for tundra, etc.

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Re: Real Time GI idea for skyrim?

Sorry, i can't use them, don't touch engine that deeply.
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