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Fixed in 2021.2.X

Fixed in 2018.4.X, 2019.4.X, 2020.3.X, 2021.1.X



Found in



Issue ID




"Assertion failed on expression: 'pred(*previous, *i)' " is thrown on additively adding a new scene to a baked scene

Progressive Lightmapper


Assertion failed on expression: 'pred(*previous, *i)' is thrown when a new scene is added additively to an existing baked scene having the "Auto-generate" checkbox off in Lighting settings. Refer the attached video

Steps to reproduce:
1) Download the attached project and open `s1Blue` scene
2) Check "Auto-generate" checkbox ON in Lighting settings and let the scene's lighting auto-bake
3) Uncheck the "Auto-Generate" checkbox in the Lighting window
4) Drag the 's1Red' scene from the Project folder to the Hierarchy to additively load it

Actual result: Assertion failed on expression: 'pred(*previous, *i)' is thrown when a scene is added additively to an existing baked scene

Expected result: No errors are thrown when a scene is added additively

Occurring on: 2019.3.0f6 (69ba09c9b97e), 2019.3.0f3

Working fine on: 2020.1.0a19, 2020.1.0a1, 2019.3.0f2

Environment: Only on Windows

Stack trace: Assertion failed on expression: 'pred(*previous, *i)'
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

  1. Resolution Note (fix version 2021.1):

    Verified fix in,

    Version: 2021.1.0b12.2144
    Revision: 2021.1/staging 7b84efee645b
    Built: Thu, 11 Mar 2021 10:21:39 GMT

  2. Resolution Note (fix version 2019.4):

    Verified fix in,

    Version 2019.4.22f1 (9fdda2fe27ad)
    Wed, 03 Mar 2021 01:24:36 GMT
    Branch: 2019.4/staging

Comments (6)

  1. Kleptine

    Feb 04, 2021 22:17

    Can confirm! Please fix!

  2. GamerTobbe

    Oct 16, 2020 13:34

    Happening on windows Unity 2019.4.12f1 (LTS)
    We loading multiplee scenes and get same amount of errors, kinda annoying and dunno if it affects build performance for leaks?

  3. KHUnity7

    Aug 25, 2020 19:56

    Happening on windows Unity 2019.4.8f1 (LTS)

  4. Huxii

    Jul 07, 2020 17:57

    Same issue. I am having the same error Messages in Unity 2019.4.0f1 on Windows.

  5. larryPlayablStudios

    May 02, 2020 00:56

    For context, here is my stack trace for this same error, from the editor log:

    Assertion failed on expression: 'pred(*previous, *i)'
    (Filename: ./Runtime/Utilities/remove_duplicates.h Line: 77)

  6. Incode

    May 01, 2020 19:28

    Happening on Mac as well.

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