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Votes

16

Found in

2020.3.35f1

2021.3.5f1

2022.1.6f1

2022.2.0a17

2023.1.0a2

2023.2.0a1

Issue ID

UUM-5698

Regression

No

OnTriggerEnter and OnTriggerExit not working correctly when changing transform and reparenting Articulation Bodies

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Reproduction steps:
1. Open the attached project "1421306.zip"
2. Enter Play Mode
3. Observe the Console window when the "Detectable" GameObject enters, is inside, and exits the "Detector" GameObject

Expected result: OnTriggerEnter is not detected when the "Detectable" is inside the "Detector". OnTriggerExit is detected when the "Detectable" leaves the "Detector".
Actual result: OnTriggerEnter is detected. OnTriggerExit is not detected.

Reproducible with: 2020.3.35f1, 2021.3.4f1, 2022.1.3f1, 2022.2.0a13
Could not test: 2019.4.39f1 - no Articulation Body

Reproduced on: Windows 10 Pro

Notes
- The "Detectable" GameObject is set to be the parent of the "Detector" GameObject when the "Detectable" is inside the "Detector"

  1. Resolution Note:

    One particular limitation of articulation bodies is that one cannot change transforms for them run-time, that stems from the fact that ABs are simulated in the reduced space and any hierarchy change, and most of the transform change kinds requires rebuilding the whole hierarchy.

    That said, pretty much the only transform change allowed is teleporting root. Setting transforms values directly will be ignored (they are simply not listened for). Changing parent requires rebuilding both of the affected articulations. Because of that rebuild, we have to remove objects from the scene and add them back.

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