NetworkAnimator bug in Netcode 1.1

[Chien-65]

Description

I got a null exception in NetworkAnimator.BuildTransitionStateInfoList. Because I only have transition.destinationStateMachine for some transitions, no transition.destinationState. This happen when I upgrade from Netcode 1.0 to Netcode 1.1. This also cause syncing issue from animation state to animation state machine.

Reproduce Steps

1. Create an animator for a character.
2. Create an idle animation state and attack animation state machine. Then create an animation transition connect idle and attack with attack trigger parameter.
3. Inside attack animation state machine, you can create two animation states like sword attack and axe attack.
4. Create an animation transition connect entry node to sword attack state with weapon type int parameter(value 0).
5. Create an animation transition connect entry node to axe attack state with weapon type int parameter(value 1).
6. When you play the game, then you will see a null exception for transition.destinationState in NetworkAnimator.BuildTransitionStateInfoList function.

Actual Outcome

An null exception, also the animation will no sync correctly.

Expected Outcome

No null exception and the animation sync correctly between client and server.

Screenshots

Environment

• OS: Windows
• Unity Version: 2021.3.9f1
• Netcode Version: 1.1m here. Logs, code snippets would be useful here but please also consider attaching a minimal Unity project that reproduces the issue.

[NoelStephensUnity]

Hello @Akyang65,
I apologize for this over-sight on my behalf while trying to address other issues with synchronizing state transitions. Let me look into replicating your scenario on my end (if you can share a culled down version of your setup it would greatly reduce my time to fix this issue correctly).
Once I have replicated the issue on my end I can create a PR with the fix.

[ashwinimurt]

MTT-5083

[NoelStephensUnity]

@Akyang65
Could you send me some screenshots of how you have your attack layer setup and the Sub-State Machine as well?
I would like to make sure I create the same thing on this end to validate a WIP fix.

[Chien-65]

Hi,

I create a test project (testproject.zip) from the "https://github.com/Unity-Technologies/com.unity.netcode.gameobjects/tree/develop/testproject".

Once you open it, please open the SampleScene. When you play as host, you first will see the null exception. After you fix it, you can press space on the host side. You should see it enter "Dagger State" on the client side. I hope this help.

[NoelStephensUnity]

That is even better (thank you)! It wasn't as much as knowing where and why the exception was happening as much as I wanted to make sure everything still synchronizes for connected and late joining clients. This will be a great help. 👍
💯