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    Sorry if this sound completely noob, but you're talkin too pro in here and just got me wondering:
    Right now as of 4.7, for a full project (i mean not just tests but a project that will someday become a full game xD) which system is best recommended? DFGI or the *old* LPVGI or any other approach i may have missed?

    Sorry if this is a question that shouldn't be here.
    "sic parvis magna"
    @Meguido

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      Originally posted by Meguido View Post
      Right now as of 4.7, for a full project (i mean not just tests but a project that will someday become a full game xD) which system is best recommended? DFGI or the *old* LPVGI or any other approach i may have missed?
      A few posts back Daniel said it won't be included until 4.8 and then it will be disabled by default until the performance/quality/features are all up to standards which I would expect will be several release cycles from now--the graphics guys need some time to sleep too. Right now in 4.7 your only options would be LPV, baked static GI, or direct lighting.

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        Originally posted by Meguido View Post
        Sorry if this sound completely noob, but you're talkin too pro in here and just got me wondering:
        Right now as of 4.7, for a full project (i mean not just tests but a project that will someday become a full game xD) which system is best recommended? DFGI or the *old* LPVGI or any other approach i may have missed?

        Sorry if this is a question that shouldn't be here.
        Given my small knowledge about this, i would say it depends of what kind of game :
        - If it is a game with relatively small outdoors (really most games) then it would definitly still be Lighmass GI by now.
        - If your game is mostly outdoors then you should consider some non-baked Global Illumination between LPV/DFGI because Lightmass GI become extremely RAM hungry on very big levels.
        - I would never advise VXGI because it will likely need a killer Nvidia graphic card for a while.
        - And for android games, then direct lighting?

        As for me i'm only interested about GI because i'm lazy to learn how to make all these UV ***** works correctly...so i prefer to dump on graphic quality and framerate to gain large amounts of time for really fastly done real time ArchViz
        Last edited by Sunny94; 02-27-2015, 10:30 PM.

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          Thanks both for your answers!
          Well in my game i'll need dynamic light cuz it'll include day-night.
          Is a vast world too (i probably could call it open-world but maybe it's not exactly that :P), it'll have more outdoor than indoor probably but still it'll have both. So i can assume LPV will work cool for an "open-world" kind of game?
          "sic parvis magna"
          @Meguido

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            @Jacky, thanks, I must've skipped over that post or something. Although I'm still unsure how the engine handles a fall-back in case of a lower-end GPU.

            Originally posted by Meguido View Post
            Thanks both for your answers!
            Well in my game i'll need dynamic light cuz it'll include day-night.
            Is a vast world too (i probably could call it open-world but maybe it's not exactly that :P), it'll have more outdoor than indoor probably but still it'll have both. So i can assume LPV will work cool for an "open-world" kind of game?
            LPV would work for that, but DFAO/DFGI seems to be the more supported implementation.
            PSX Shaders | Gangster Weapon Pack | Free Weapon Pack | Various Free Models

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              Sorry if i put this here, but since i started learning ue4, and now reading this thread i'm lost with all the GI solutions.

              Simply, when i launch the 1st person template, and hit Build, what method do i use? Lightmass GI? (Here when it goes over my available Ram, the comp freezes)
              I'm reading a lot about every aspect of the engine, but could someone summarize what are the differences between Lightmass GI, LPV, DFGI, VXGI, where are they, when/why should i use one or the other? Are they dependant on the used lights types (static/movable)?

              Thanks in advance
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                Originally posted by DaveFace View Post
                LPV would work for that, but DFAO/DFGI seems to be the more supported implementation.
                but DFGI is not available in 4.7 isn't it?
                "sic parvis magna"
                @Meguido

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                  Originally posted by Meguido View Post
                  but DFGI is not available in 4.7 isn't it?
                  And version available in 4.8 won't be ready to release.
                  If you want to use dynamic GI you have accept that DFGI is currently WIP part of engine. Work on other parts of your project, having in mind DFGI is coming. Forget about LPV - it's limited implementation and I doubt Epic will develop it in foreseeable future.

                  I'm reading a lot about every aspect of the engine, but could someone summarize what are the differences between Lightmass GI, LPV, DFGI, VXGI, where are they, when/why should i use one or the other? Are they dependant on the used lights types (static/movable)?
                  1. Lightmass GI - static GI with extremely beautiful results. Pros - you bake GI on developer PC and end users(players) CPU/GPU don't have to calculate this part of rendering, it's pre-baked and will work very efficiently. Cons - it static. If you move any object - GI is broken.
                  2. LPV - dynamic GI with good results. Pros - it's fully dynamic, you can move lights and objects without breaking GI. Cons - it's unoptimized and very heavy on players PC, a lot of light leaking with thin meshes, thin spaces and etc. Afaik it's "frozen" project for now.
                  3. DFGI - dynamic GI with good results.Pros - It's fully dynamic, do light leaks, works good with any meshes and more customizable in terms of performance. Cons - it's currently in development and not finished by any means. A lot of optimization work should be done and some bug fixing, but if everything work out - we will get superb GI that works good in outdoors scene AND in indoors!
                  4. VXGI - dynamig GI with more than good results, but works on top nvidia cards only(Not 100% sure though) and very-very costly.
                  Last edited by zeOrb; 02-28-2015, 12:53 PM.
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                    Thanks for your explanation, very clear, but to be sure:
                    So by default in 4.7, Build = Lightmass?
                    DFGI as the next proprietary GI solution, already available in 4.7 in experimental mode, and in normal mode in 4.8?
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                      Originally posted by David Boura View Post
                      Thanks for your explanation, very clear, but to be sure:
                      So by default in 4.7, Build = Lightmass?
                      DFGI as the next proprietary GI solution, already available in 4.7 in experimental mode, and in normal mode in 4.8?
                      Not exactly, it is static GI solution, so in next versions it won't be replaced by DFGI. It's like different tools for different tasks.
                      DFGI is next dynamic proprietary GI solution. Afaik in 4.7 it's disabled and you won't get access to it before 4.8(Well, if you don't use Github ofc)
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                      Level design and prototyping for newbies

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                        Thank you!
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                        https://soundcloud.com/davidboura

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                          I finally found out why i was "unable" to see any difference between putting rDistanceFieldGI=1 in my conf file or not!

                          First, i did not knew i could check it with Show->Visualize->Distance Field Global Illumination.
                          Then, i had two directional lights in my scene (well...it was nicer with it lol) and the GI is totally ignoring my second directional light which is by far the strongest and so it was very hard to notice any difference between with GI or not!
                          Last edited by Sunny94; 02-28-2015, 04:51 PM.

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                            Originally posted by zeOrb View Post
                            And version available in 4.8 won't be ready to release.
                            If you want to use dynamic GI you have accept that DFGI is currently WIP part of engine. Work on other parts of your project, having in mind DFGI is coming. Forget about LPV - it's limited implementation and I doubt Epic will develop it in foreseeable future.

                            1. Lightmass GI - static GI with extremely beautiful results. Pros - you bake GI on developer PC and end users(players) CPU/GPU don't have to calculate this part of rendering, it's pre-baked and will work very efficiently. Cons - it static. If you move any object - GI is broken.
                            2. LPV - dynamic GI with good results. Pros - it's fully dynamic, you can move lights and objects without breaking GI. Cons - it's unoptimized and very heavy on players PC, a lot of light leaking with thin meshes, thin spaces and etc. Afaik it's "frozen" project for now.
                            3. DFGI - dynamic GI with good results.Pros - It's fully dynamic, do light leaks, works good with any meshes and more customizable in terms of performance. Cons - it's currently in development and not finished by any means. A lot of optimization work should be done and some bug fixing, but if everything work out - we will get superb GI that works good in outdoors scene AND in indoors!
                            4. VXGI - dynamig GI with more than good results, but works on top nvidia cards only(Not 100% sure though) and very-very costly.

                            About VXGI, for now it has many bugs and lacking features like emissive materaisl aren't part of their GI system for now, the same for indirect specular. Also VXGI is programmed to only have one bounce level which is not eneough for many scenes since some areas don't get lit by just one bounce thus the lack of many needed results like indirect refelctions.

                            Does DFGI work interiors for the time being? How many bounces does it have (I hope at least two to be reasonable)? Will it be available to to 4.8 preview when it comes to launcher? Thanks !

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                              Originally posted by PLASTICA-MAN View Post
                              About VXGI, for now it has many bugs and lacking features like emissive materaisl aren't part of their GI system for now, the same for indirect specular. Also VXGI is programmed to only have one bounce level which is not eneough for many scenes since some areas don't get lit by just one bounce thus the lack of many needed results like indirect refelctions.

                              Does DFGI work interiors for the time being? How many bounces does it have (I hope at least two to be reasonable)? Will it be available to to 4.8 preview when it comes to launcher? Thanks !
                              I can answer this for you:

                              VXGI emissive:

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                              DFGI emissive:

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                              Although DFGI may have a significantly greater performance now compared to VXGI, this is the level of quality you will get if you look closely.
                              I'm not sure how the quality of DFGI can be improved in the future whilst still having a competitive performance to VXGI - simply because VXGI uses Hardware Filtering which comes naturally from using a 3D Texture. Whereas, it seems that DFGI has to be filtered manually. Then again, DF shadows seem to be really good quality (not sure how its done yet) whereas the quality of voxel based shadows are heavily dependent on the voxel resolution.

                              DFGI is also only capable of diffuse reflections (not specular).

                              DFGI currently only has a single bounce as well.

                              I discovered from the 4.7 release that it now works for point lights and spotlights.

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                                So I just had a look at the DFGI code. I noticed that it samples the SceneColor texture - i.e. this texture has both direct and indirect lighting composited. Correct me if I am wrong, but technically in every following frame, it should sample the indirect lighting which is added to the texture, thus creating multiple bounces. But something seems to be stopping it from doing that. I'm thinking it may be because it is in screen-space thus areas which cannot be seen cannot contribute to a bounce. However, a scene should exhibit color bleeding when only an emissive object is active (with no other lights) - yet it doesn't.

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