fix: match NetworkAnimator transition info by originating state only

Transitions not in the table no longer fall back to the first entry for the destination, and a missing sub-state machine reference no longer throws while the table is built.

Author: NoelStephensUnity

com.unity.netcode.gameobjects/Runtime/Components/NetworkAnimator.cs

@@ -300,8 +300,8 @@ private void BuildDestinationToTransitionInfoTable()
         }
 
         /// <summary>
-        /// Gets the transition info for a destination state, preferring the entry that starts from the originating state
-        /// since several states can transition into the same destination.
+        /// Gets the transition info for a destination state, matched by originating state since several states can
+        /// transition into the same destination. Transitions not in the table, such as non-trigger ones, return false.
         /// </summary>
         internal bool TryGetTransitionInfo(int layer, int destinationState, int originatingState, out TransitionStateInfo transitionInfo)
         {
@@ -311,16 +311,15 @@ internal bool TryGetTransitionInfo(int layer, int destinationState, int originat
                 return false;
             }
 
-            transitionInfo = transitions[0];
             foreach (var entry in transitions)
             {
                 if (entry.OriginatingState == originatingState)
                 {
                     transitionInfo = entry;
-                    break;
+                    return true;
                 }
             }
-            return true;
+            return false;
         }
 
         [Serializable]
@@ -493,7 +492,11 @@ private void ParseStateMachineStates(int layerIndex, ref AnimatorController anim
             foreach (var childStateMachine in stateMachine.stateMachines)
             {
                 var nestedStateMachine = childStateMachine.stateMachine;
-                ParseStateMachineStates(layerIndex, ref animatorController, ref nestedStateMachine, childStateMachineParents);
+                // A missing sub-state machine asset reference leaves this null
+                if (nestedStateMachine != null)
+                {
+                    ParseStateMachineStates(layerIndex, ref animatorController, ref nestedStateMachine, childStateMachineParents);
+                }
             }
         }
 
@@ -1104,14 +1107,11 @@ private void WriteSynchronizationData<T>(ref BufferSerializer<T> serializer) whe
                         stateHash = nextState.fullPathHash;
 
                         // Check if this transition can be synchronized using cross-fading
-                        if (m_DestinationStateToTransitionInfo.ContainsKey(layer))
+                        if (TryGetTransitionInfo(layer, nextState.shortNameHash, synchronizationStateInfo.shortNameHash, out var transitionInfo))
                         {
-                            if (TryGetTransitionInfo(layer, nextState.shortNameHash, synchronizationStateInfo.shortNameHash, out var transitionInfo))
-                            {
-                                stateHash = transitionInfo.OriginatingState;
-                                // Set the destination state to cross-fade to from the originating state
-                                animationState.DestinationStateHash = transitionInfo.DestinationState;
-                            }
+                            stateHash = transitionInfo.OriginatingState;
+                            // Set the destination state to cross-fade to from the originating state
+                            animationState.DestinationStateHash = transitionInfo.DestinationState;
                         }
                     }
 

com.unity.netcode.gameobjects/Tests/Editor/NetworkAnimatorEditorTests.cs

@@ -239,6 +239,7 @@ public void TransitionInfoLookupMatchesOriginatingState()
             Assert.That(networkAnimator.TryGetTransitionInfo(0, stateB.nameHash, stateC.nameHash, out var infoFromC), Is.True);
             Assert.That(infoFromC.OriginatingState, Is.EqualTo(stateC.nameHash));
             Assert.That(infoFromC.TransitionDuration, Is.EqualTo(transitionFromC.duration));
+            Assert.That(networkAnimator.TryGetTransitionInfo(0, stateB.nameHash, stateB.nameHash, out _), Is.False);
         }
 
         private TestNetworkAnimator CreateNetworkAnimator(AnimatorController controller, string name)