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    The shadows do look dark (had the skylight set to 1). Here's a comparison of intensity 1-3:

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      Originally posted by The_Distiller View Post
      @Laserman: You did tick "Generate mesh distance field" in the projects settings under rendering right?

      @Nick!: I haven't tested it in a real indoor environment, yet. I think it's too early for that, since the current iteration of the tech has lots of artifacts in shadowed areas.

      Yeah, I enabled that via the consolveVariables.ini and double checked it via the preferences and it was enabled.

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        Originally posted by TheJamsh View Post
        Is it me, or do Shadows look insanely dark even at midday? Mind you I don't think this is necessarily anything to do with the DFGI implementation, more just games in general. I mean, if you go outside in that environment IRL, you'd probably see hardly any shadow at all, or if you did it'd be considerably more lit up and faded than that.
        This is one of my biggest pet peeves with video game rendering. I think a lot of artists rely too heavily on the game's GI solution and are unwilling to accept that general lighting is really necessary. Actually, not only does light bounce an infinite number of times in real life (whereas lightmass only computes 3 bounces, and most dynamic GI solutions only compute up to 2 bounces), but light is practically coming from everywhere: the sun emits light, which is then scattered by the atmosphere, which then hits a multitude of surfaces scattering all that light in all directions. Generally speaking, most of the light is coming from the sun of course, but light is omnipresent until the sun recedes below the horizon and the sky dims.

        Any dynamic GI solution should have some sort of ambiance measure that doesn't need to be too accurate but simulates this kind of general lighting from all over. I'm pretty sure just trying to replicate light bouncing is not going to be enough because of how multi-directional light in the real world really is.

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          Originally posted by mariomguy View Post
          This is one of my biggest pet peeves with video game rendering. I think a lot of artists rely too heavily on the game's GI solution and are unwilling to accept that general lighting is really necessary. Actually, not only does light bounce an infinite number of times in real life (whereas lightmass only computes 3 bounces, and most dynamic GI solutions only compute up to 2 bounces), but light is practically coming from everywhere: the sun emits light, which is then scattered by the atmosphere, which then hits a multitude of surfaces scattering all that light in all directions. Generally speaking, most of the light is coming from the sun of course, but light is omnipresent until the sun recedes below the horizon and the sky dims.

          Any dynamic GI solution should have some sort of ambiance measure that doesn't need to be too accurate but simulates this kind of general lighting from all over. I'm pretty sure just trying to replicate light bouncing is not going to be enough because of how multi-directional light in the real world really is.
          This is exactly what ambient occlusion does.

          Edit: Also, skylight.
          Last edited by fastcar25; 02-16-2015, 12:25 AM.

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            would like to see this GI used on the elemental demo and compare it with the SVOGI version and a VXGI & AHR version

            a showdown of the ages!

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              I just downloaded the Master Branch, can't see to get the distance field GI to work, when I'm using visualize distance field global illumination I just get black. I got a moveable skylight and moveable directional, and r.DistanceFieldGI=1 and r.GenerateMeshDistanceFields=1 in ConsoleVariables.ini

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                Thanks, I got it working.

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                  This is all amazing work! I don't understand ANY of it but it all looks awesome!
                  KITATUS
                  "Information shouldn't be behind a paywall, It should be free for all!"

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                    The shadows do look dark (had the skylight set to 1). Here's a comparison of intensity 1-3:
                    There's no second or higher bounce lighting supported yet, which is why the ground is so dark.

                    Due to the limited bounce distance and single bounce you definitely need other light sources to rely on, not just GI like you could with Lightmass baked lighting. For outdoors this means a skylight, for indoors it means multiple overlapping lights. I hope to improve these aspects but one step at a time.

                    There's a lot of splotchiness on clean flat surfaces due to the interpolation method, and a lot of noise on foliage due to the low resolution sampling. These are ongoing challenges.

                    So far with the Surfel GI approach (the one The_Distiller posted all the beautiful images of) I have been going for leak-free or at least limited leaking, as this will be used in indoors scenes. This is a big challenge to do in realtime with larger bounce distances, which is why the bounce distance is fairly short (10m by default, you can increase with the skylight MaxOcclusionDistance). For the Heightfield GI I have been going for longer bounce distances with less accurate indirect shadowing (aka more leaking). This looks better with outdoor natural scenes like foliage and terrain, where light bounces everywhere and you never expect fully black. In the final solution which mixes both Surfel GI and Heightfield GI, I'm expecting to expose controls so you can pick whether you want 'no leaking' or 'longer bounces'.

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                      Baking seems to happen in Editor code, which is a bit of a shame as you can't include those parts in a shipping game in case you do some runtime landscape modification
                      That's true, I didn't expect changing landscape materials to be important for now so those textures are baked. It's possible to evaluate them on the fly to support dynamic changes, it wouldn't even be a big change to the algorithm, it would just cost more GPU time. However with surfel GI material changes will be fully supported.

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                        I think a lot of artists rely too heavily on the game's GI solution and are unwilling to accept that general lighting is really necessary. Actually, not only does light bounce an infinite number of times in real life (whereas lightmass only computes 3 bounces
                        That is incorrect, Lightmass computes as many bounces as you request of it, the default is 3 and the upper limit is 10.

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                          just got it working! that is pretty motherflipping cool. got some noise, but man, looking forward to the upcoming releases.

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                            This is exactly what ambient occlusion does.

                            Edit: Also, skylight.
                            Yes, I know. But there are plenty of student projects and even professional ones that don't. After doing some research, it seems stationary skylights can change color and intensity as necessary, which is awesome, so that can totally work as an ambient solution in tandem with GI.

                            That is incorrect, Lightmass computes as many bounces as you request of it, the default is 3 and the upper limit is 10.
                            Well, this is nicer. I think the issue I kept seeing with games (not naming names) is they just forget to add skylights and environment lights. That's not really Lightmass's fault, so, I'm sorry for misconstruing it.

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                              Originally posted by DanielW View Post
                              There's no second or higher bounce lighting supported yet, which is why the ground is so dark.

                              Due to the limited bounce distance and single bounce you definitely need other light sources to rely on, not just GI like you could with Lightmass baked lighting. For outdoors this means a skylight, for indoors it means multiple overlapping lights. I hope to improve these aspects but one step at a time.

                              There's a lot of splotchiness on clean flat surfaces due to the interpolation method, and a lot of noise on foliage due to the low resolution sampling. These are ongoing challenges.

                              So far with the Surfel GI approach (the one The_Distiller posted all the beautiful images of) I have been going for leak-free or at least limited leaking, as this will be used in indoors scenes. This is a big challenge to do in realtime with larger bounce distances, which is why the bounce distance is fairly short (10m by default, you can increase with the skylight MaxOcclusionDistance). For the Heightfield GI I have been going for longer bounce distances with less accurate indirect shadowing (aka more leaking). This looks better with outdoor natural scenes like foliage and terrain, where light bounces everywhere and you never expect fully black. In the final solution which mixes both Surfel GI and Heightfield GI, I'm expecting to expose controls so you can pick whether you want 'no leaking' or 'longer bounces'.
                              Mixed results might be best, tight surfel GI shadowing the heightfield GI, even if the shadowing distance is small it will look better. As for thin geometry and particles, I've found success with what I call "box sampling". Just take the AABB of your asset, or whatever box you want, and sample GI in a sphere from the center. You can then construct, whatever, a spherical harmonic term to apply to the resulting geometry and you're still going deferred. Works with transparent stuff too but then you don't really get specular for glass or whatever unless you sample enough to not make it worth it to begin with. Still, you can specular sample as normal for a pane of glass if you have that set up, then "box" sample for the diffuse, if it's transparent enough it looks fine.

                              There's errors from this of course. But you can sample higher from a single spherical sample than trying to go per pixel on all that stuff, and then apply whatever hacky corrections you can think of like blending it with nearby "boxes" or etc.

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                                So to clearify this subject:

                                I can have DFGI starting with 4.8 builds as an active option and then it may get even better (faster, higher quality) with later builds ?
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