Search Unity

Question How do i change the shadowmask at runtime?

Discussion in 'Global Illumination' started by LeoOB, Mar 30, 2023.

  1. LeoOB

    LeoOB

    Joined:
    Sep 4, 2017
    Posts:
    1
    Im currently using this script to change my lightmapping data at runtime:
    https://github.com/MahmoudKanbar/Unity-Dynamic-Lightmaps
    I made some changes to it so i can also swap things like ambient color, skyboxes and such, but now im trying to also switch the shadowmasks at runtime.
    Currently i wanna use shadowmasks only for static objects so im using the shadowmask mode in quality settings, and it works well when i switch to the latest lightmap i baked for the scene, but when i try to load the next one its only rendering dynamic shadows for every object in the scene and i see a noticeable increase on the triangle count (going from around 150k to 470k)

    To change the shadowmask i made sure to save its textures to the LightState assets, and to switch lightmaps the method UpdateLightMapsSettings() gets called (also inside the LightState script)

    Code (CSharp):
    1. public void UpdateLightMapsSettings()
    2.         {
    3.             var newLightmapData = new LightmapData[Size];
    4.  
    5.             for (int i = 0; i < Size; i++)
    6.             {
    7.                 newLightmapData[i] = new LightmapData();
    8.                 newLightmapData[i].lightmapColor = colorMaps[i];
    9.                 newLightmapData[i].lightmapDir = directionMaps[i];
    10.                 newLightmapData[i].shadowMask = shadowMasks[i]; //This is the line i added
    11.             }
    12.  
    13.             LightmapSettings.lightmaps = newLightmapData;
    14.             LightmapSettings.lightProbes.bakedProbes = lightProbesData;
    15. ...
    Am i missing something? i thought by adding the shadowmask textures to the new lightmap data they would also get changed
     
    LeoOB, Mar 30, 2023
    #1

  2. Pema-Malling

    Pema-Malling

    Unity Technologies

    Joined:
    Jul 3, 2020
    Posts:
    320
    The code you have looks sane, but this isn't the only data that feeds into shadowmask rendering. There is also Light.lightBakingOutput (https://docs.unity3d.com/ScriptReference/Light-bakingOutput.html). For each light, this struct contains:
    - A flag indicating whether the light has been baked
    - An enum indicating which part of the lights contribution was baked
    - The mixed lighting mode used for the light
    - The channel in the relevant shadowmask to use for the light
    - The channel in the relevant per-probe-occlusion data to use for the light (like shadowmask, but for probes)

    This struct isn't serialized in the editor like most other data on lights - it's ephemeral data which is usually patched into the scene on load or when a bake has finished. Only when building the player is it serialized into the build (iirc).

    Anyways, if you are messing with shadowmasks, you might want to have a look at these values. You might have to patch them up along with the shadowmask texture, depending on your setup.
     
    Pema-Malling, Apr 4, 2023
    #2
    giorgos_unity likes this.

  3. Kragh

    Kragh

    Joined:
    Jan 22, 2008
    Posts:
    657
    Thank you! Thank you, thank you, thank you! After having struggled ALL DAY with why my distance shadowMasks weren't showing up when the light rt shadows faded out, I finally find the solution here :) Copy/Paste of the the mixed lights BakingOutput settings to the new scenes matching lights (Debug mode in Inspector, and they show up, and can be copy/pasted with right click)
    Having made a system that sets all the other things automatically (So that I can have prefabs with lightmaps from a main scene), this was completely mysterious to me. Works!
     
    Kragh, Oct 12, 2023
    #3