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We have decided not to address this issue at this moment. The mass ratio is outside of what can be expected reliable simulation from. Also, from a theoretical perspective both behaviours (pre-change, and after change) are incorrect: before the change the large body would pierce through the small one and only accidentally drag it together at around exit from collision, after the change it won't pierce through but there might be arguably questionable reciprocal motion. It's a consequence of an otherwise good change that addressed CCD objects tunnelling in certain conditions. We might reconsider this resolution later.
Cancelling this 2023.2 tech release issue since the support for this release has come to end of life. Cancelling this 2023.2 port case does not affect any LTS or Unity 6 Beta/Preview that remain open.
How to reproduce:
1. Open the “HeavyObjectBug.zip“ project
2. Open the “TestScene“
3. Enter Play Mode
4. Observe the Game view
Expected results: The heavy GameObject does not stutter on collision with light GameObjects
Actual results: the heavy GameObject stutters on collision with light GameObjects
Reproducible in: 2021.3.30f1, 2021.3.36f1, 2022.3.8f1, 2022.3.20f1, 2023.2.13f1, 2023.3.0b10
Not reproducible in: 2021.3.29f1, 2022.3.7f1
Reproduced on: Windows 11 Pro (23H2)
Not reproduced on: No other environment tested
Note: The issue is very visible when the “CubeLight“ GameObjects have a mass of 1, and the “SphereHeavy“ GameObject has a mass of 1000
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