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TES Skyrim development

Posted: 17 Mar 2013, 18:10
by ENBSeries
Can't decide how to make distant fog fading, so posting shots modified in image editor, criticize them (one is vanilla fog):

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There is no data by height of the fog, so to make correct looking distance fog impossible, guess nobody will do special objects which represent fog height in game world, but if only such data could be available, then several different effects could be done.
Long time ago i tried to blend distant fog as transparency of sky, but result is even worse than artufacts of classic game distance fogging. Tried to make clouds only blended on the rocks depending from fog amount - also bad. Third idea i tried for skyrim is to apply fog to sky based on top-horizon angle and fog density, but the sky get fogged too much in this case, because it's depth is infinite, so all objects looks unfogged on such foggy sky. Another issue with such method is when looking at very high object, it's top is fogged, but sky is not, so original artifact present and new one.


Here is the real samples where common bug of distance fog not exist because of height
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Re: TES Skyrim development

Posted: 17 Mar 2013, 18:27
by Rubber-De-Flubber
I'd have to say I like both the 2nd and 4th ones. The second one could be good for most screenshots, but sometimes I just feel like I need a lot of fog in my shots. Either one is fine with me, though.

Re: TES Skyrim development

Posted: 17 Mar 2013, 19:50
by Kermles
Hmm, I like the 4th one the best. I love how you can see it has settled in the valley. The third one looks almost as good but slightly resembles low clouds instead of fog, like the gradient is too sharply decreasing from top to bottom. The 2nd one is good but I think looks unnatural near the top, like the fog is painted on. First one looks not bad but a little plain compared to the others, although it would be good for some scenes that aren't supposed to have too much fog, like very distant scenery on a sunny day.

To me the 4th one is just about right :)

Re: TES Skyrim development

Posted: 17 Mar 2013, 20:14
by chan
I like 2 and 3.

For me, I want fog to be reliant on IBL.

If I have little clouds in the sky, then IBL should be bright, and if I have a lot of clouds, IBL should be 0. If IBL is 1, then no fog, and if IBL is 0, then a lot of fog, like in 2 and 3 screen-shots.

Re: TES Skyrim development

Posted: 17 Mar 2013, 21:22
by mindflux
Hard to say without knowing the weather type, I guess it depends on how the new fog will react to parameters in the CK. Number 2 looks more realistic for the weather type shown in the screens, but maybe I'd pick number 4, assuming that fog thickness can still be altered in ordinary means via enbseries.ini and the CK. I haven't researched how fog is usually implemented in modern engines, but it often looks a lot 'smoother' than for example in Skyrim, which I guess just uses a simple overlay. It's really a shame that height fog is not possible, but understandable.

By the way, any chance of atmospheric light scattering with the Skyrim engine?

Re: TES Skyrim development

Posted: 18 Mar 2013, 05:12
by ENBSeries
About two or three weeks i'm trying to find solution for volumetric lighting of fog, which is similar to atmospheric scattering, but only partially computed. Even this have many problems which can't solve (at least haven't found how to do this). Shadow in game drawed not from sun direction (possible to make correction, but at cost of some artifacts), it's ignore many objects as shadow casters, especially distant rocks which are occluders for sun. When camera moving or rotating, effect "flow" and flicker in some places, i don't like this. Render objects outside of screen for masking could help a little, but performance...
Simplest lit fog like this one (without computing occluders and only at far distance) is very bad looking when sun is hidden by rocks or player entering cave:
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Re: TES Skyrim development

Posted: 19 Mar 2013, 00:39
by far327
2 seems balanced. 4 seems balanced as well. 1 is too vanilla like... 3 just looks strange to me.

I think 2 would be my number one choice!

Re: TES Skyrim development

Posted: 19 Mar 2013, 03:15
by evok99
I like 2 and 3. 2 does not have enough fog. 3 has too much fog. Somewhere in between. 2.5

Re: TES Skyrim development

Posted: 19 Mar 2013, 07:06
by SiSaSyco
2 looks good for me, because it blends the Mountains nicely in the Sky.
4 Would be good for more dense fog, but without looking like clouds, but I guess that looking like clouds is because of 2D-Image editing to show effect, is it?

Re: TES Skyrim development

Posted: 19 Mar 2013, 09:17
by ENBSeries
That looks like clouds, because it's blurred rocks, which brighter than sky on the image. Of course depth is not exist on such edited image, but it's close enough to ideas i have. These all are just walkarounds for hiding artifacts with vanilla fog, some blurring is good for rainy weather or real fog, but it's not what i need to show on screenshots. Don't know, may be to make height of the fog relative to camera, fast moving in world will give strange results i guess (whe i tried shadows from clouds, it's very noticable that they move with camera as relative to it instead of world).