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    #31
    I did some quick tests too.

    (to speed up the testing I use lowres lightmaps)



    I use this values in editor parameters :

    Static Lighting Level Scale : 0.1
    Num Indirect Lighting Bounces : 100
    Indirect Lighting Quality : 10
    Indirect Lighting Smoothness : 1

    And in the BaseLightmass.ini :

    NumHemisphereSamplesScale=100

    In my tests, this is the only parameter you need to tweak in baselightmass.ini to remove the skylight "splotches".





    And stop using my old BaseLightmass.ini, like I already say, it's roughtly just random values^^.
    You don't need to boost all the values if you just light your scene with a skylight.

    With the spot/reflector technique (that simulate a skylight with more than 2 bounces) you need more tweaks (and more render time) to have a good quality.
    Last edited by koola; 10-25-2015, 08:48 AM.
    ____________________________________________________________
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      #32
      Great finding Koola!
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        #33
        Thanks for the info Koola. I would like to hear Daniel chime in on this before we all take it as the gospel.

        "And in the BaseLightmass.ini :

        NumHemisphereSamplesScale=100

        In my tests, this is the only parameter you need to tweak in baselightmass.ini to remove the skylight "splotches".

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          #34
          Originally posted by koola View Post
          I did some quick tests too.

          (to speed up the testing I use lowres lightmaps)



          I use this values in editor parameters :

          Static Lighting Level Scale : 0.1
          Num Indirect Lighting Bounces : 100
          Indirect Lighting Quality : 10
          Indirect Lighting Smoothness : 1

          And in the BaseLightmass.ini :

          NumHemisphereSamplesScale=100

          In my tests, this is the only parameter you need to tweak in baselightmass.ini to remove the skylight "splotches".





          And stop using my old BaseLightmass.ini, like I already say, it's roughtly just random values^^.
          You don't need to boost all the values if you just light your scene with a skylight.

          With the spot/reflector technique (that simulate a skylight with more than 2 bounces) you need more tweaks (and more render time) to have a good quality.
          @Koola - What a perfect timing, Now we got all the fuel we required to boost Lightmass learning. If possible kindly have a look on the level with spot lights for the light leak errors.

          I have to confess that I am already using NumHemisphereSamplesScale=64 Value on all of my latest projects without touching other values much (I found this during my experiments that this value is greatly improving the results). But again all I know was this value is improving my results but how? and why? are the questions which still need answers. Light leaks are still unresolved on .1 Value in Static Lighting Level Scale.

          @DanielW - I am becoming desperate to know your findings. My hopes are super high. Kindly provide explanation behind all this.

          Looking Forward.
          Raghu
          http://rag3dviz.com
          HDRI Lighting Tutorial
          Basic UVW Workflow Tutorial

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            #35
            Static Lighting Level Scale : 0.1
            Num Indirect Lighting Bounces : 100
            Indirect Lighting Quality : 10
            Indirect Lighting Smoothness : 1

            And in the BaseLightmass.ini :

            NumHemisphereSamplesScale=100


            Is this even possible to use those in a real scene and without a huge renderfarm tho? :-S

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              #36
              Originally posted by heartlessphil View Post
              Static Lighting Level Scale : 0.1
              Num Indirect Lighting Bounces : 100
              Indirect Lighting Quality : 10
              Indirect Lighting Smoothness : 1

              And in the BaseLightmass.ini :

              NumHemisphereSamplesScale=100


              Is this even possible to use those in a real scene and without a huge renderfarm tho? :-S
              Im wondering about this as well, especially cranking up the Indirect Lighting Quality adds sooo much render time.
              And I actually found that a value of 2-3 gives me a much cleaner result than anything over that.
              My Porfolio

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                #37
                I experienced certain unpredictability of result depending on position of Lightmass Volume. The position seems obvious, it should encompass the scene. But how much ? By atleast 1 or 10perc. ?
                Generally you want all surfaces that need good quality to be contained, plus 10m more or less. The different results from changing it slightly are probably because it redistributed the photons, and there was enough noise from photons in the first place. In other words, there was significant noise present and changing any parameter slightly will shift the noise. The volume is just one of those parameters.

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                  #38
                  Which is also why other renderers brought more advanced secondary solvers (for example Vray's LightCache, while also not perfect esp. when it comes to lightleaks, it's far more evolved than photon mapping
                  I did a quick search, their LightCache is what's known as Importance tracing. It's not a replacement for photon mapping, in fact you can combine the two nicely. Importance tracing = trace from the eye, photon mapping = trace from the light. Many lighting situations, like bright sun hitting a small spot and illuminating the whole room, require a mix of both. In the case of Lightmass though we are building lightmaps, there is no eye position, so it's not applicable.

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                    #39
                    Originally posted by sandermer View Post
                    Im wondering about this as well, especially cranking up the Indirect Lighting Quality adds sooo much render time.
                    And I actually found that a value of 2-3 gives me a much cleaner result than anything over that.
                    I've done scenes with .9, 100, 10, .66 and it took round 7 hours on 2 machines. Not too bad! Under 10 hours is ok-ish but over 10 hours it's a bit long. Koola might use a bigger renderfarm who knows!

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                      #40
                      Regarding each single parameter on the .ini file, well if DanieW is willing to share some knowledge would be great.
                      See post #8.

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                        #41
                        I use this values in editor parameters :

                        Static Lighting Level Scale : 0.1
                        Num Indirect Lighting Bounces : 100
                        Indirect Lighting Quality : 10
                        Indirect Lighting Smoothness : 1

                        And in the BaseLightmass.ini :

                        NumHemisphereSamplesScale=100
                        Thanks for sharing your results koola.

                        NumHemisphereSamples is how many rays will be traced at the base level of refinement for the final gather, which means direct shadowing for a skylight. IndirectLightingQuality already scales NumHemisphereSamples. So those settings are equivalent to massive brute force, something like 16k rays before adaptive sampling even kicks in, which explains the render times.

                        Personally I won't spend over 20 minutes building lighting for such a small scene but I know you guys are going for maximum quality.

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                          #42
                          Most people serious about arch-viz probably have access to a decent render-farm. Even if it takes 10 hours for the final bake, this isn't a big problem as long as it's predictable in the end!

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                            #43
                            Daniel:

                            Is it possible to give us something like this? In Modo for example if there is noise I know to increase the samples in the lights. So, for us non technical people can we get an over view like.
                            Blotchy try x, x and x
                            Light leaks, increase lightmap rez and x
                            Etc.

                            All this tech talk makes my head spin. Hahahaha

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                              #44
                              Originally posted by RI3DVIZ View Post
                              Daniel:

                              Is it possible to give us something like this? In Modo for example if there is noise I know to increase the samples in the lights. So, for us non technical people can we get an over view like.
                              Blotchy try x, x and x
                              Light leaks, increase lightmap rez and x
                              Etc.

                              All this tech talk makes my head spin. Hahahaha
                              There you go!
                              https://wiki.unrealengine.com/Lighti...eshootingGuide
                              Theia Interactive makes immersive VR experiences in collaboration with the world’s leading companies and creatives, leveraging this bleeding edge technology to pioneer the next generation of entertainment, storytelling, and customer engagement.

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                                #45
                                Originally posted by StephaBon View Post
                                Oh! I'm going to check those at home, getting lots of weird issues in my level.

                                Thanks for sharing you guys.

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