fix: mixed authority nested NetworkTransform stops updating non-authority nested NetworkTransforms by NoelStephensUnity · Pull Request #4169 · Unity-Technologies/com.unity.netcode.gameobjects

NoelStephensUnity · 2026-09-24T15:42:22Z

Purpose of this PR

This resolves the issue with mixed authority nested NetworkTransform instances can stop child/nested NetworkTransform instances from updating due to a parent (root or otherwise) NetworkTransform that is the authority instance will remove the NetworkObject completely from the non-authority update group causing non-authority instances to never update their state (interpolating or not).

fix: #4159

Jira ticket

UUM-153570

Changelog

Fixed: issue with mixed authority nested NetworkTransform instances can stop child/nested NetworkTransform instances from updating due to a parent (root or otherwise) NetworkTransform that is the authority instance will remove the NetworkObject completely from the non-authority update group causing non-authority instances to never update their state (interpolating or not) on the authority side.

Documentation

No documentation changes or additions were necessary.

Testing & QA (How your changes can be verified during release Playtest)

Functional Testing

Manual testing :

Manual testing done

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Covered by new automated tests

Does the change require QA team to:

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Up-port

Requires an up-port.

Backports

No back-port required.

Fixing issue where a `NetworkObject` with nested `NetworkTransform` components using different `NetworkTransform.AuthorityMode` settings stop updating non-authority instances, because the first authority instance removes the entire `NetworkObject` from the update registration.

The tests that validate this fix.

Adding changelog entry

u-pr · 2026-09-24T15:44:57Z

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u-pr

💡 Harness Review

The mixed-authority registration fix works for transforms sharing an update scheduler, but mishandles nested transforms split between frame and physics updates.

_{Reviewed commit ff196a3}

_{🤖 Helpful? 👍/👎}

Updating comments for clarity

Addressing the u-pr bot's findings.

Adding a test to validate the, now fixed, gap u-pr bot found.

NoelStephensUnity · 2026-09-24T20:05:20Z

@u-pr please review again

u-pr · 2026-09-24T20:08:49Z

Review Summary

The latest updates cleanly address the previous feedback:

Scheduler Awareness in HasNonAuthorityNetworkTransform:
- Accepting forUpdate and filtering out instances configured for a different update stage (forUpdate == networkTransform.m_UseRigidbodyForMotion) ensures registration checks in InternalInitialization only consider transforms operating in the same scheduler (standard update vs. fixed update).
- This prevents authoritative components from prematurely unregistering a NetworkObject that still contains non-authoritative transforms needing the same update loop.
Integration Test Coverage:
- Parameterizing NetworkTransformMixedAuthorityTests across host/server and authority mode permutations provides thorough validation for nested synchronization.
- The new NetworkTransformMixedMotionModelTests confirms that update registration follows the motion model across ownership transfers.

A minor suggestion was left inline regarding an initial baseline assertion in UpdateRegistrationFollowsMotionModel. Overall, the implementation looks solid.

_{🤖 Helpful? 👍/👎}

Applying u-pr's suggestion to this test.

codecov-github-com · 2026-09-24T23:17:41Z

Codecov Report

All modified and coverable lines are covered by tests ✅

@@                Coverage Diff                @@
##           develop-2.0.0    #4169      +/-   ##
=================================================
+ Coverage          74.10%   74.14%   +0.03%     
=================================================
  Files                172      172              
  Lines              28127    28144      +17     
=================================================
+ Hits               20844    20867      +23     
+ Misses              7283     7277       -6

Flag	Coverage Δ
NGOv2_project_testproject_ubuntu	`73.74% <100.00%> (-0.04%)`	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...gameobjects/Runtime/Components/NetworkTransform.cs	`89.14% <100.00%> (+0.35%)`	⬆️

Components	Coverage Δ
com.unity.netcode.gameobjects	`74.14% <100.00%> (+0.03%)`	⬆️

ℹ️ Need help interpreting these results?

…m-updates

EmandM

Looks good, mostly just worried about the number of tests added

EmandM · 2026-09-25T14:53:31Z

+    [TestFixture(HostOrServer.Host, NetworkTransform.AuthorityModes.Server)]
+    [TestFixture(HostOrServer.Host, NetworkTransform.AuthorityModes.Owner)]
+    [TestFixture(HostOrServer.Server, NetworkTransform.AuthorityModes.Server)]
+    [TestFixture(HostOrServer.Server, NetworkTransform.AuthorityModes.Owner)]


Do we need both host and server tests here? Seems overkill maybe?

Looking into this.

EmandM · 2026-09-25T14:54:33Z

        private void MovePlayers()
        {
-            foreach (var networkManager in m_NetworkManagers)
+            foreach (var networkManager in m_ClientNetworkManagers)


Why do we only want the client managers rather than all managers?

Reviewing an alternate approach for this.
This was specific to the issue being resolved which only occurs with a dedicated server (i.e. has no client).

EmandM · 2026-09-25T14:55:30Z

+        private NetworkObject GetAuthorityInstance(NetworkManager player, NetworkTransform.AuthorityModes authorityMode)
+        {
+            var authority = authorityMode == NetworkTransform.AuthorityModes.Server ? m_ServerNetworkManager : player;
+            return authority.SpawnManager.SpawnedObjects[player.LocalClient.PlayerObject.NetworkObjectId];


It's probably worth moving a function like this down into the base NetcodeIntegrationTest. A GetManagersInstance or something like that.

Agreed it belongs in the base. Moving it there.

NoelStephensUnity added 3 commits September 24, 2026 10:34

fix

6b2f648

Fixing issue where a `NetworkObject` with nested `NetworkTransform` components using different `NetworkTransform.AuthorityMode` settings stop updating non-authority instances, because the first authority instance removes the entire `NetworkObject` from the update registration.

test

e98ed18

The tests that validate this fix.

update

ff196a3

Adding changelog entry

NoelStephensUnity marked this pull request as ready for review September 24, 2026 15:44

NoelStephensUnity requested a review from a team as a code owner September 24, 2026 15:44

u-pr Bot reviewed Sep 24, 2026

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Comment thread com.unity.netcode.gameobjects/Runtime/Components/NetworkTransform.cs

NoelStephensUnity added 3 commits September 24, 2026 10:51

style

bef6418

Updating comments for clarity

fix

1bef954

Addressing the u-pr bot's findings.

test

8920574

Adding a test to validate the, now fixed, gap u-pr bot found.

NoelStephensUnity mentioned this pull request Sep 24, 2026

fix: [Up-port] mixed authority nested NetworkTransform stops updating non-authority nested NetworkTransforms #4170

Open

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u-pr Bot reviewed Sep 24, 2026

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Comment thread ....netcode.gameobjects/Tests/Runtime/NetworkTransform/NetworkTransformMixedMotionModelTests.cs

update

674b7d2

Applying u-pr's suggestion to this test.

Merge branch 'develop-2.0.0' into fix/mixed-authority-nested-transfor…

fd5b4f0

…m-updates

EmandM reviewed Sep 25, 2026

View reviewed changes

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fix: mixed authority nested NetworkTransform stops updating non-authority nested NetworkTransforms - #4169

fix: mixed authority nested NetworkTransform stops updating non-authority nested NetworkTransforms#4169
NoelStephensUnity wants to merge 8 commits into
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