CMCL-0000: CameraDeactivated events were not sent when a blend interrupted another

com.unity.cinemachine/CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this package will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [3.1.3] - 2025-12-31
+
+### Bugfixes
+- CameraDeactivated events were not sent consistently when a blend interrupted another blend before completion.
+
+
 ## [3.1.2] - 2024-10-01
 
 ### Added

com.unity.cinemachine/Runtime/Core/BlendManager.cs

@@ -102,8 +102,7 @@ public bool IsLiveInBlend(ICinemachineCamera cam)
 
         /// <summary>
         /// Compute the current blend, taking into account
-        /// the in-game camera and all the active overrides.  Caller may optionally
-        /// exclude n topmost overrides.
+        /// the in-game camera and all the active overrides.  
         /// </summary>
         public void ComputeCurrentBlend() 
         {
@@ -129,8 +128,6 @@ public void RefreshCurrentCameraState(Vector3 up, float deltaTime)
         public ICinemachineCamera ProcessActiveCamera(ICinemachineMixer mixer, Vector3 up, float deltaTime)
         {
             // Send deactivation events
-            m_CameraCache.Clear();
-            CollectLiveCameras(m_PreviousLiveCameras, ref m_CameraCache);
             for (int i = 0; i < m_CameraCache.Count; ++i)
                 if (!IsLive(m_CameraCache[i]))
                     CinemachineCore.CameraDeactivatedEvent.Invoke(mixer, m_CameraCache[i]);
@@ -146,7 +143,7 @@ public ICinemachineCamera ProcessActiveCamera(ICinemachineMixer mixer, Vector3 u
 
                 if (incomingCamera == outgoingCamera)
                 {
-                    // Send a blend completeed event if appropriate
+                    // Send a blend completed event if appropriate
                     if (m_PreviousLiveCameras.CamA != null && m_CurrentLiveCameras.CamA == null)
                         CinemachineCore.BlendFinishedEvent.Invoke(mixer, incomingCamera);
                 }
@@ -176,7 +173,10 @@ public ICinemachineCamera ProcessActiveCamera(ICinemachineMixer mixer, Vector3 u
                     incomingCamera.UpdateCameraState(up, deltaTime);
                 }
             }
-            return incomingCamera;
+
+            // Collect cameras that are live this frame, for processing next frame
+            m_CameraCache.Clear();
+            CollectLiveCameras(m_CurrentLiveCameras, ref m_CameraCache);
 
             // local method - find all the live cameras in a blend
             static void CollectLiveCameras(CinemachineBlend blend, ref List<ICinemachineCamera> cams)
@@ -191,6 +191,8 @@ static void CollectLiveCameras(CinemachineBlend blend, ref List<ICinemachineCame
                 else if (blend.CamB != null)
                     cams.Add(blend.CamB);
             }
+
+            return incomingCamera;
         }
     }
 }

com.unity.cinemachine/Runtime/Helpers/CinemachineCameraEvents.cs

@@ -81,7 +81,7 @@ void OnCameraActivated(ICinemachineCamera.ActivationEventParams evt)
 
         void OnBlendCreated(CinemachineCore.BlendEventParams evt)
         {
-            if (evt.Blend.CamA == (ICinemachineCamera)EventTarget || evt.Blend.CamB == (ICinemachineCamera)EventTarget)
+            if (evt.Blend.CamB == (ICinemachineCamera)EventTarget)
                 BlendCreatedEvent.Invoke(evt);
         }
 

com.unity.cinemachine/Tests/Editor/BlendManagerTests.cs

@@ -29,6 +29,7 @@ public FakeMixer(string name) : base(name) {}
         FakeMixer m_Mixer = new ("Mixer");
         FakeCamera m_Cam1 = new ("Cam1");
         FakeCamera m_Cam2 = new ("Cam2");
+        FakeCamera m_Cam3 = new ("Cam3");
 
         int m_ActivatedEventCount;
         int m_DeactivatedEventCount;
@@ -57,21 +58,26 @@ [TearDown] public void TearDown()
 
         void ResetCounters() => m_ActivatedEventCount = m_DeactivatedEventCount = m_BlendCreatedCount = m_BlendFinishedCount = 0;
 
-        void ProcessFrame(ICinemachineCamera cam, float deltaTime)
+        void Reset(float blendTime)
         {
-            m_BlendManager.UpdateRootFrame(m_Mixer, cam, Vector3.up, deltaTime);
+            m_BlendManager.LookupBlendDelegate = (outgoing, incoming)
+                => new (CinemachineBlendDefinition.Styles.EaseInOut, blendTime); // constant blend time
+            m_BlendManager.ResetRootFrame();
+            ProcessFrame(null, 0.1f);
+            ResetCounters();
+        }
+
+        void ProcessFrame(ICinemachineCamera activeCam, float deltaTime)
+        {
+            m_BlendManager.UpdateRootFrame(m_Mixer, activeCam, Vector3.up, deltaTime);
             m_BlendManager.ComputeCurrentBlend();
             m_BlendManager.ProcessActiveCamera(m_Mixer, Vector3.up, deltaTime);
         }
 
         [Test]
         public void TestEvents()
         {
-            m_BlendManager.LookupBlendDelegate = (outgoing, incoming)
-                => new (CinemachineBlendDefinition.Styles.EaseInOut, 1); // constant blend time of 1
-
-            ResetCounters();
-            m_BlendManager.ResetRootFrame();
+            Reset(1); // constant blend time of 1
 
             // We should get an initial activation event, no blend
             ProcessFrame(m_Cam1, 0.1f);
@@ -110,5 +116,65 @@ public void TestEvents()
             Assert.AreEqual(1, m_BlendFinishedCount);
             Assert.That(m_BlendManager.IsBlending, Is.False);
         }
+
+        [Test]
+        public void TestEventsNestedBlend()
+        {
+            Reset(1); // constant blend time of 1
+
+            // We should get an initial activation event, no blend
+            ProcessFrame(m_Cam1, 0.1f);
+            Assert.AreEqual(1, m_ActivatedEventCount);
+            Assert.AreEqual(0, m_DeactivatedEventCount);
+            Assert.AreEqual(0, m_BlendFinishedCount);
+            Assert.AreEqual(0, m_BlendCreatedCount);
+            Assert.That(m_BlendManager.IsBlending, Is.False);
+
+            ProcessFrame(m_Cam1, 0.1f);
+            Assert.AreEqual(1, m_ActivatedEventCount);
+            Assert.AreEqual(0, m_DeactivatedEventCount);
+            Assert.AreEqual(0, m_BlendCreatedCount);
+            Assert.AreEqual(0, m_BlendFinishedCount);
+            Assert.That(m_BlendManager.IsBlending, Is.False);
+
+            // Activate new camera, blend will take 1 sec
+            ProcessFrame(m_Cam2, 0.1f);
+            Assert.AreEqual(2, m_ActivatedEventCount);
+            Assert.AreEqual(0, m_DeactivatedEventCount);
+            Assert.AreEqual(1, m_BlendCreatedCount);
+            Assert.AreEqual(0, m_BlendFinishedCount);
+            Assert.That(m_BlendManager.IsBlending, Is.True);
+
+            ProcessFrame(m_Cam2, 0.5f);
+            Assert.AreEqual(2, m_ActivatedEventCount);
+            Assert.AreEqual(0, m_DeactivatedEventCount);
+            Assert.AreEqual(1, m_BlendCreatedCount);
+            Assert.AreEqual(0, m_BlendFinishedCount);
+            Assert.That(m_BlendManager.IsBlending, Is.True);
+
+            // Acivate new cam before old blend is finished
+            ProcessFrame(m_Cam3, 0.1f);
+            Assert.AreEqual(3, m_ActivatedEventCount);
+            Assert.AreEqual(0, m_DeactivatedEventCount);
+            Assert.AreEqual(2, m_BlendCreatedCount);
+            Assert.AreEqual(0, m_BlendFinishedCount);
+            Assert.That(m_BlendManager.IsBlending, Is.True);
+
+            // After first blend time has elapsed, check the counters
+            ProcessFrame(m_Cam3, 0.5f);
+            Assert.AreEqual(3, m_ActivatedEventCount);
+            Assert.AreEqual(1, m_DeactivatedEventCount);
+            Assert.AreEqual(2, m_BlendCreatedCount);
+            Assert.AreEqual(0, m_BlendFinishedCount); // blend was interrupted, never finished
+            Assert.That(m_BlendManager.IsBlending, Is.True);
+
+            // After second blend is finished, check the counters
+            ProcessFrame(m_Cam3, 0.5f);
+            Assert.AreEqual(3, m_ActivatedEventCount);
+            Assert.AreEqual(2, m_DeactivatedEventCount);
+            Assert.AreEqual(2, m_BlendCreatedCount);
+            Assert.AreEqual(1, m_BlendFinishedCount);
+            Assert.That(m_BlendManager.IsBlending, Is.False);
+        }
     }
 }

com.unity.cinemachine/package.json

@@ -1,7 +1,7 @@
 {
   "name": "com.unity.cinemachine",
   "displayName": "Cinemachine",
-  "version": "3.1.2",
+  "version": "3.1.3",
   "unity": "2022.3",
   "description": "Smart camera tools for passionate creators. \n\nCinemachine 3 is a newer and better version of Cinemachine, but upgrading an existing project from 2.X will likely require some effort.  If you're considering upgrading an older project, please see our upgrade guide in the user manual.",
   "keywords": [