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    #31
    Originally posted by Terrian View Post
    You realize that what you just described is one of the core points behind PBR systems... Physically Based Rendering.

    I'm glad the trend is to remove hacky features. What you call "artistically crippled" I call "logically sound".
    I'm just saying that the current ways to tweak the fog seems somewhat limited.
    Unreal is a game engine, not a nature simulator. If artists can't have creative control then we are doing something wrong.

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      #32
      What determines the ParticleRadius Node in Materials?
      Cascade doesn't have a module "Radius"

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        #33
        Originally posted by Terrian View Post
        You realize that what you just described is one of the core points behind PBR systems... Physically Based Rendering.

        I'm glad the trend is to remove hacky features. What you call "artistically crippled" I call "logically sound".
        you have to realize that not everyone is trying to make games with realistic graphics. there's a big artistic component in video games which is up to... well to the artists making those games.
        games with unique art styles (Zelda BotW, ABZU or DOTA2 to name a few) are only possible because game engines don't force an entire shading philosophy down their throat.
        I think people making non-realistic artstyles will only fight against the engine for so long until they get tired and move on to a different engine
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          #34
          Originally posted by Chosker View Post
          you have to realize that not everyone is trying to make games with realistic graphics. there's a big artistic component in video games which is up to... well to the artists making those games.
          games with unique art styles (Zelda BotW, ABZU or DOTA2 to name a few) are only possible because game engines don't force an entire shading philosophy down their throat.
          I think people making non-realistic artstyles will only fight against the engine for so long until they get tired and move on to a different engine
          ABZU runs on UE4, and started development when UE4 was still new and didn't have all the features it has now. And no-one is being forced to use Unreal. And if anyone wants to do something else with Unreal, the source is available. The developers of ABZU did that. No-one can expect Epic to literally do everything everyone wants.

          ----

          On top of that, this is "volumetric lighting/fog". Light shafts are supposed to appear based on the fog. If someone only wants light shafts, that's a completely different graphical feature, like the built-in shafts (which are limited I agree).

          I agree on the part that only supporting PBR can block someone's artistic view, but I would rather embrace it than criticize it. Especially after seeing Gearbox' presentation during GDC, as I was somewhat skeptical before.

          Of course, this is all just my opinion.
          Portfolio: https://www.artstation.com/final-frontier
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            #35
            Originally posted by Raildex_ View Post
            What determines the ParticleRadius Node in Materials?
            Cascade doesn't have a module "Radius"
            Particle size I presume.

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              #36
              Originally posted by stargatefreak92 View Post
              Of course, this is all just my opinion.
              I share your opinion. And given time I think people will figure out what artistic overrides are possible and which, if any, it makes sense for epic to add to this system.

              I suspect that some of the scenarios people are complaining that the system cannot handle will be achievable once people have had more time to experiment with all of the options and especially the use of volume materials & particle systems to influence the degree of fog present in particular regions.

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                #37
                Originally posted by SteveElbows View Post
                Particle size I presume.
                Click image for larger version

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                I don't think so:/

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                  #38
                  Originally posted by SteveElbows View Post
                  I share your opinion. And given time I think people will figure out what artistic overrides are possible and which, if any, it makes sense for epic to add to this system.

                  I suspect that some of the scenarios people are complaining that the system cannot handle will be achievable once people have had more time to experiment with all of the options and especially the use of volume materials & particle systems to influence the degree of fog present in particular regions.
                  Didn't mean to start such a discussion


                  What I feel is missing in particular is most likely adressed with some cutoff/distance settings.

                  What I want: A more distinct cut where the border of the fog is. So it's more noticeable.
                  What I don't want: To feel that the scene is so foggy.

                  If I could set a short fog distance and high intensity. Then the fog should be the same for close and far objects. I guess that could be a start.

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                    #39
                    Originally posted by Raildex_ View Post
                    [ATTACH=CONFIG]138945[/ATTACH]
                    I don't think so:/
                    Just because the size of each particle in X,Y,Z is available with the particle size node, doesnt mean particle radius is unrelated to particle size.

                    Here is what the manual says:

                    The ParticleRadius expression outputs the radius in Unreal units of each particle individually. This allows, for example, for changes to be made to a material once the radius has reached a certain point.

                    Taken from: https://docs.unrealengine.com/latest...particleradius

                    edited to add - I followed the example for creating a very simple volume material and it uses ParticleRadius fed into SphereMask radius. ParticleSize is not used. But when I change the size of the particles by editing the particle system, I see the changes I expect, and this is why I am so confident that ParticleRadius is influenced by the size of particles in practice not just in theory.
                    Last edited by SteveElbows; 04-28-2017, 09:42 AM.

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                      #40
                      Originally posted by stargatefreak92 View Post
                      ABZU runs on UE4, and started development when UE4 was still new and didn't have all the features it has now. And no-one is being forced to use Unreal. And if anyone wants to do something else with Unreal, the source is available. The developers of ABZU did that. No-one can expect Epic to literally do everything everyone wants.
                      not everyone has the manpower to dive into the engine to change its rendering features.
                      I'm not saying Epic should literally do everything everyone wants (though they did design UE4 with the philosophy to be much more open than UE3 and cater a broader audience) - I'm just expecting Epic to not make features as "opt-in" only if you're making a game with realistic graphics. Especially since exposing a few parameters could go a long way into getting that freedom, as opposed to "deeply learning how the every parameter works so you can find workarounds to actually achieve what you want" as others seem to be suggesting

                      Originally posted by stargatefreak92 View Post
                      On top of that, this is "volumetric lighting/fog". Light shafts are supposed to appear based on the fog. If someone only wants light shafts, that's a completely different graphical feature, like the built-in shafts (which are limited I agree).

                      I agree on the part that only supporting PBR can block someone's artistic view, but I would rather embrace it than criticize it. Especially after seeing Gearbox' presentation during GDC, as I was somewhat skeptical before.

                      Of course, this is all just my opinion.
                      I agree this is the "volumetric lighting/fog" feedback thread, I'm just saying that it doesn't have to be. it could very well be the "underwater fog effect" or the "alien planet atmosphere effect" or the "high fantasy light effect" if they weren't so inclined into forcing physical properties into every single rendering feature
                      Follow me on Twitter!
                      Developer of Elium - Prison Escape
                      Local Image-Based Lighting for UE4

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                        #41
                        ^Oh, I haven't found the ParticleRadius Documentation, I thought it is new in 4.16. THank you

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                          #42
                          Originally posted by Chosker View Post
                          I'm just expecting Epic to not make features as "opt-in" only if you're making a game with realistic graphics. Especially since exposing a few parameters could go a long way into getting that freedom, as opposed to "deeply learning how the every parameter works so you can find workarounds to actually achieve what you want" as others seem to be suggesting

                          I agree this is the "volumetric lighting/fog" feedback thread, I'm just saying that it doesn't have to be. it could very well be the "underwater fog effect" or the "alien planet atmosphere effect" or the "high fantasy light effect" if they weren't so inclined into forcing physical properties into every single rendering feature
                          I dont think PBR and physically based effects etc are only about creating realistic looking games at all. And I did not mean to suggest that extremely deep and confusing learning must be undertaken in order to do something different. My point along those lines was more about how early it is and that people havent yet had much chance to share their tips for how to do various things.

                          I found it very easy to create stuff with the new system that does not look realistic at all, especially if I start playing with emissive colour of a volume material, or playing with particle lights or the colour of other lights.

                          I do not mean to claim that there are no missing options, eg it does sound like some additional cutoff controls will be necessary for certain situations. But physically based stuff is more about the underlying maths and the language used to describe options, about consistency and what not to bake into materials for artistic but rigid control. It's not just about delivering results that must always reflect the way we are used to seeing light behave on planet earth. But depending on the maths used some of the stuff you might want is not simply hidden from the user, waiting to be exposed, but simply not part of the equation at all. Depending on the detail some could be added in quite trivially, whilst others might impede the entire philosophy of the physically based approach but in many situation I think a happy balance will be found that does not leave artists who want to crank things 'beyond the norm' out in the cold at all.

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                            #43
                            Is manually placing particles in the buildings that try to fill the building geometry as closely as possible really the only way to remove the fog in the buildings?
                            I hope in the future we will have some sculpting tools for 3d fog density. Then you can place a 'fog volume' and just paint density within it, straight into the level. Then you just don't paint inside.

                            I haven't played with the new fog yet, but is it possible to simulate the Tyndall Effect, IE: blue light gets reflected, and red/orange light gets transmitted?
                            Not at the moment. Tyndall effect happens more with Raleigh Scattering, which is caused by tiny atmosphere particles, much smaller than the dust / smoke / haze / fog particles that Volumetric Fog is simulating. It would still be cool though. It adds some cost as you have to store 3 extinctions, one for each channel.

                            Can you explain a bit more about how particle sprites trigger the fog field?
                            Basically the Volume material is run on every voxel inside the particle's bounding sphere. You can output Albedo (reflectivity), Extinction and Emissive for every point in that space. Usually you texture using WorldPosition. Only particle sprites supported correctly atm.

                            Is there a way to decouple volumetric fog center from the camera? Ie something like vxgi anchor? It would be very useful for top down games.
                            Not at the moment. Standalone volumes would be very cool, although it's hard to integrate them with translucency efficiently.

                            BTW....if you look at volumetric lighting in Horizon Zero Dawn...they have some nice lightshafts too, but their stuff is also quite foggy
                            The main thing they have going on is the fog is restricted to only be dense in the low areas. This is the key to getting cool volumetric lighting without it being so strong. Don't turn it up globally, then you can't see to play the game. Have it be more dense in low areas, and in areas where you have 'painted' it in with particles, and in areas where you have localized spot lights.

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                              #44
                              I feel this is a general problem with the current state of PBR in UE4. There are a lot of minor settings that would have helped artists a lot, but are not added because they are not "correct".
                              And the current implementation of volumetric fog seems to go down the same path of being physically correct, but artistically crippled.
                              There are a bunch of volumetric fog settings which are not physically based already. VolumetricScatteringIntensity on a light for example, there is no parallel to modifying a light's participating media scattering separately from its surface scattering in real life. The energy of the light affects both equally.

                              Saying 'it should be more stylized' is not actionable. There are also infinite ways to stylize rendering, we don't try to support all of them. Where there are clearly useful artist tweaks, we add them.

                              To some extent, this volumetric fog algorithm is forced to be physically correct because it actually simulates light travelling through every unit of space, and we are limited by that. You can't just specify the final color.

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                                #45
                                I thought movable directional lights where supported? I get very weird results when the sun is set to movable.
                                Cascaded shadowmaps are supported and generally much higher quality than static shadowing from a Stationary directional light. Can you setup in a small test scene and isolate what the difference is?

                                I'm getting weird side effects when using high res screen shot tool. it's different each time I try.
                                Thanks for the bug report, I'll add that to my list to fix. High res screenshot has some unique requirements.

                                Are there plans in the future to support a separate cascaded shadow map for the fog? Having to reduce overall shadow quality or the number of cascades for the directional light is a little unfortunate.
                                Why do you have to reduce overall shadow quality, or the number of cascades?

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