FIX: MouseDownEvent is triggered when changing from Scene view to Game view (ISXB-1671)

.github/pull_request_template.md

@@ -11,8 +11,8 @@ _Please describe the testing already done by you and what testing you request/re
 
 _Please rate the potential complexity and halo effect from low to high for the reviewers. Note down potential risks to specific Editor branches if any._
 
-- Complexity: 
-- Halo Effect: 
+- Complexity:
+- Halo Effect:
 
 ### Comments to reviewers
 
@@ -45,7 +45,3 @@ During merge:
     - `DOCS: ___`.
     - `CHANGE: ___`.
     - `RELEASE: 1.1.0-preview.3`.
-
-After merge:
-
-- [ ] Create forward/backward port if needed. If you are blocked from creating a forward port now please add a task to ISX-1444.

Assets/Tests/InputSystem/CoreTests_Actions.cs

@@ -642,6 +642,56 @@ public void Actions_DoNotGetTriggeredByEditorUpdates()
         }
     }
 
+    [Test]
+    [Category("Actions")]
+    [Description("Tests that that only the latest event after focus is regained is able to trigger the action." +
+        "Depends on background behavior. ")]
+    [TestCase(InputSettings.BackgroundBehavior.IgnoreFocus)]
+    [TestCase(InputSettings.BackgroundBehavior.ResetAndDisableNonBackgroundDevices)]
+    [TestCase(InputSettings.BackgroundBehavior.ResetAndDisableAllDevices)]
+    public void Actions_DoNotGetTriggeredByOutOfFocusEventInEditor(InputSettings.BackgroundBehavior backgroundBehavior)
+    {
+        InputSystem.settings.backgroundBehavior = backgroundBehavior;
+
+        var mouse = InputSystem.AddDevice<Mouse>();
+        var mousePointAction = new InputAction(binding: "<Mouse>/position", type: InputActionType.PassThrough);
+        mousePointAction.Enable();
+
+        using (var trace = new InputActionTrace(mousePointAction))
+        {
+            currentTime += 1.0f;
+            runtime.PlayerFocusLost();
+            currentTime += 1.0f;
+            // Queuing an event like it would be in the editor when the GameView is out of focus.
+            Set(mouse.position, new Vector2(0.234f, 0.345f) , queueEventOnly: true);
+            currentTime += 1.0f;
+            // Gaining focus like it would happen in the editor when the GameView regains focus.
+            runtime.PlayerFocusGained();
+            currentTime += 1.0f;
+            // This emulates a device sync that happens when the player regains focus through an IOCTL command.
+            // That's why it also has it's time incremented.
+            Set(mouse.position, new Vector2(1.0f, 2.0f), queueEventOnly: true);
+            currentTime += 1.0f;
+            // This update should not trigger any ction as it's an editor update.
+            InputSystem.Update(InputUpdateType.Editor);
+            currentTime += 1.0f;
+
+            var actions = trace.ToArray();
+            Assert.That(actions, Has.Length.EqualTo(0));
+            // This update should trigger an action with regards to the event queued after focus was regained.
+            // The one queued while out of focus should have been ignored and we should expect only one action triggered.
+            // Unless background behavior is set to IgnoreFocus in which case both events should trigger the action.
+            InputSystem.Update(InputUpdateType.Dynamic);
+
+            actions = trace.ToArray();
+            Assert.That(actions, Has.Length.EqualTo(backgroundBehavior == InputSettings.BackgroundBehavior.IgnoreFocus ? 2 : 1));
+            Assert.That(actions[0].phase, Is.EqualTo(InputActionPhase.Performed));
+            Vector2Control control = (Vector2Control)actions[0].control;
+            // Make sure the value is from the event after focus was regained.
+            Assert.That(control.value, Is.EqualTo(new Vector2(1.0f, 2.0f)).Using(Vector2EqualityComparer.Instance));
+        }
+    }
+
     [Test]
     [Category("Actions")]
     public void Actions_TimeoutsDoNotGetTriggeredInEditorUpdates()

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -28,6 +28,7 @@ however, it has to be formatted properly to pass verification tests.
 - Fixed the compilation warnings when used with Unity 6.4 (ISX-2349).
 - Fixed an issue where `InputSystemUIInputModule.localMultiPlayerRoot` could not be set to `null` when using `MultiplayerEventSystem`. [ISXB-1610](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1610)
 - Fixed an issue in `Keyboard` where the sub-script operator would return a `null` key control for the deprecated key `Key.IMESelected`. Now, an aliased `KeyControl`mapping to the IMESelected bit is returned for compability reasons. It is still strongly advised to not rely on this key since `IMESelected` bit isn't strictly a key and will be removed from the `Key` enumeration type in a future major revision. [ISXB-1541](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1541).
+- An issue where a UITK MouseEvent was triggered when changing from Scene View to Game View in the Editor has been fixed. [ISXB-1671](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1671)
 
 ## [1.14.2] - 2025-08-05
 

Packages/com.unity.inputsystem/InputSystem/InputManager.cs

@@ -2244,6 +2244,8 @@
         private bool m_NativeBeforeUpdateHooked;
         private bool m_HaveDevicesWithStateCallbackReceivers;
         private bool m_HasFocus;
+        private bool m_DiscardOutOfFocusEvents;
+        private double m_FocusRegainedTime;
         private InputEventStream m_InputEventStream;
 
         // We want to sync devices when the editor comes back into focus. Unfortunately, there's no
@@ -3032,6 +3034,8 @@
             }
             else
             {
+                m_DiscardOutOfFocusEvents = true;
+                m_FocusRegainedTime = m_Runtime.currentTime;
                 // On focus gain, reenable and sync devices.
                 for (var i = 0; i < m_DevicesCount; ++i)
                 {
@@ -3201,50 +3205,20 @@
             var timesliceEvents = (updateType == InputUpdateType.Fixed || updateType == InputUpdateType.BeforeRender) &&
                 InputSystem.settings.updateMode == InputSettings.UpdateMode.ProcessEventsInFixedUpdate;
 
-            // Figure out if we can just flush the buffer and early out.
-            var canFlushBuffer =
-                false
-#if UNITY_EDITOR
-                // If out of focus and runInBackground is off and ExactlyAsInPlayer is on, discard input.
-                || (!gameHasFocus && m_Settings.editorInputBehaviorInPlayMode == InputSettings.EditorInputBehaviorInPlayMode.AllDeviceInputAlwaysGoesToGameView &&
-                    (!m_Runtime.runInBackground ||
-                        m_Settings.backgroundBehavior == InputSettings.BackgroundBehavior.ResetAndDisableAllDevices))
-#else
-                || (!gameHasFocus && !m_Runtime.runInBackground)
-#endif
-            ;
-            var canEarlyOut =
-                // Early out if there's no events to process.
-                eventBuffer.eventCount == 0
-                || canFlushBuffer
-
-#if UNITY_EDITOR
-                // If we're in the background and not supposed to process events in this update (but somehow
-                // still ended up here), we're done.
-                || ((!gameHasFocus || gameShouldGetInputRegardlessOfFocus) &&
-                    ((m_Settings.backgroundBehavior == InputSettings.BackgroundBehavior.ResetAndDisableAllDevices && updateType != InputUpdateType.Editor)
-                        || (m_Settings.editorInputBehaviorInPlayMode == InputSettings.EditorInputBehaviorInPlayMode.AllDevicesRespectGameViewFocus && updateType != InputUpdateType.Editor)
-                        || (m_Settings.backgroundBehavior == InputSettings.BackgroundBehavior.IgnoreFocus && m_Settings.editorInputBehaviorInPlayMode == InputSettings.EditorInputBehaviorInPlayMode.AllDeviceInputAlwaysGoesToGameView && updateType == InputUpdateType.Editor)
-                    )
-                    // When the game is playing and has focus, we never process input in editor updates. All we
-                    // do is just switch to editor state buffers and then exit.
-                    || (gameIsPlaying && gameHasFocus && updateType == InputUpdateType.Editor))
-#endif
-            ;
+            // Determine if we should flush the event buffer which would imply we exit early and do not process
+            // any of those events, ever.
+            var shouldFlushEventBuffer = ShouldFlushEventBuffer();
+            // When we exit early, we may or may not flush the event buffer. It depends if we want to process events
+            // later once this method is called.
+            var shouldExitEarly =
+                eventBuffer.eventCount == 0 || shouldFlushEventBuffer || ShouldExitEarlyFromEventProcessing(updateType);
 
 
 #if UNITY_EDITOR
-            var dropStatusEvents = false;
-            if (!gameIsPlaying && gameShouldGetInputRegardlessOfFocus && (eventBuffer.sizeInBytes > (100 * 1024)))
-            {
-                // If the game is not playing but we're sending all input events to the game, the buffer can just grow unbounded.
-                // So, in that case, set a flag to say we'd like to drop status events, and do not early out.
-                canEarlyOut = false;
-                dropStatusEvents = true;
-            }
+            var dropStatusEvents = ShouldDropStatusEvents(eventBuffer, ref shouldExitEarly);
 #endif
 
-            if (canEarlyOut)
+            if (shouldExitEarly)
             {
                 // Normally, we process action timeouts after first processing all events. If we have no
                 // events, we still need to check timeouts.
@@ -3253,7 +3227,7 @@
 
                 k_InputUpdateProfilerMarker.End();
                 InvokeAfterUpdateCallback(updateType);
-                if (canFlushBuffer)
+                if (shouldFlushEventBuffer)
                     eventBuffer.Reset();
                 m_CurrentUpdate = default;
                 return;
@@ -3317,25 +3291,9 @@
 
                         continue;
                     }
-#endif
 
-                    // In the editor, we discard all input events that occur in-between exiting edit mode and having
-                    // entered play mode as otherwise we'll spill a bunch of UI events that have occurred while the
-                    // UI was sort of neither in this mode nor in that mode. This would usually lead to the game receiving
-                    // an accumulation of spurious inputs right in one of its first updates.
-                    //
-                    // NOTE: There's a chance the solution here will prove inadequate on the long run. We may do things
-                    //       here such as throwing partial touches away and then letting the rest of a touch go through.
-                    //       Could be that ultimately we need to issue a full reset of all devices at the beginning of
-                    //       play mode in the editor.
-#if UNITY_EDITOR
-                    if ((currentEventType == StateEvent.Type ||
-                         currentEventType == DeltaStateEvent.Type) &&
-                        (updateType & InputUpdateType.Editor) == 0 &&
-                        InputSystem.s_SystemObject.exitEditModeTime > 0 &&
-                        currentEventTimeInternal >= InputSystem.s_SystemObject.exitEditModeTime &&
-                        (currentEventTimeInternal < InputSystem.s_SystemObject.enterPlayModeTime ||
-                         InputSystem.s_SystemObject.enterPlayModeTime == 0))
+                    // Decide to skip events based on timing or focus state
+                    if (ShouldDiscardEventInEditor(currentEventType, currentEventTimeInternal, updateType))
                     {
                         m_InputEventStream.Advance(false);
                         continue;
@@ -3695,6 +3653,8 @@
                 throw;
             }
 
+            m_DiscardOutOfFocusEvents = false;
+
             if (shouldProcessActionTimeouts)
                 ProcessStateChangeMonitorTimeouts();
 
@@ -3706,6 +3666,153 @@
             m_CurrentUpdate = default;
         }
 
+        /// <summary>
+        /// Determines if the event buffer should be flushed without processing events.
+        /// </summary>
+        /// <returns>True if the buffer should be flushed, false otherwise.</returns>
+        private bool ShouldFlushEventBuffer()
+        {
+#if UNITY_EDITOR
+            // If out of focus and runInBackground is off and ExactlyAsInPlayer is on, discard input.
+            if (!gameHasFocus &&
+                m_Settings.editorInputBehaviorInPlayMode == InputSettings.EditorInputBehaviorInPlayMode.AllDeviceInputAlwaysGoesToGameView
+                &&
+                (!m_Runtime.runInBackground || m_Settings.backgroundBehavior == InputSettings.BackgroundBehavior.ResetAndDisableAllDevices))
+                return true;
+#else
+            // In player builds, flush if out of focus and not running in background
+            if (!gameHasFocus && !m_Runtime.runInBackground)
+                return true;
+#endif
+            return false;
+        }
+
+        /// <summary>
+        /// Determines if we should exit early from event processing without handling events.
+        /// </summary>
+        /// <param name="eventBuffer">The current event buffer</param>
+        /// <param name="canFlushBuffer">Whether the buffer can be flushed</param>
+        /// <param name="updateType">The current update type</param>
+        /// <returns>True if we should exit early, false otherwise.</returns>
+        private bool ShouldExitEarlyFromEventProcessing(InputUpdateType updateType)
+        {
+#if UNITY_EDITOR
+            // Check various PlayMode specific early exit conditions
+            if (ShouldExitEarlyBasedOnBackgroundBehavior(updateType))
+                return true;
+
+            // When the game is playing and has focus, we never process input in editor updates.
+            // All we do is just switch to editor state buffers and then exit.
+            if ((gameIsPlaying && gameHasFocus && updateType == InputUpdateType.Editor))
+                return true;
+#endif
+
+            return false;
+        }
+
+#if UNITY_EDITOR
+        /// <summary>
+        /// Checks background behavior conditions for early exit from event processing.
+        /// </summary>
+        /// <param name="updateType">The current update type</param>
+        /// <returns>True if we should exit early, false otherwise.</returns>
+        /// <remarks>
+        /// Whenever this method returns true, it usually means that events are left in the buffer and should be
+        /// processed in a next update call.
+        /// </remarks>
+        private bool ShouldExitEarlyBasedOnBackgroundBehavior(InputUpdateType updateType)
+        {
+            // In Play Mode, if we're in the background and not supposed to process events in this update
+            if ((!gameHasFocus || gameShouldGetInputRegardlessOfFocus) && updateType != InputUpdateType.Editor)
+            {
+                if (m_Settings.backgroundBehavior == InputSettings.BackgroundBehavior.ResetAndDisableAllDevices ||
+                    m_Settings.editorInputBehaviorInPlayMode == InputSettings.EditorInputBehaviorInPlayMode.AllDevicesRespectGameViewFocus)
+                    return true;
+            }
+
+            // Special case for IgnoreFocus behavior with AllDeviceInputAlwaysGoesToGameView in editor updates
+            if ((!gameHasFocus || gameShouldGetInputRegardlessOfFocus) &&
+                m_Settings.backgroundBehavior == InputSettings.BackgroundBehavior.IgnoreFocus &&
+                m_Settings.editorInputBehaviorInPlayMode == InputSettings.EditorInputBehaviorInPlayMode.AllDeviceInputAlwaysGoesToGameView &&
+                updateType == InputUpdateType.Editor)
+                return true;
+
+            return false;
+        }
+
+        /// <summary>
+        /// Determines if status events should be dropped and modifies early exit behavior accordingly.
+        /// </summary>
+        /// <param name="eventBuffer">The current event buffer</param>
+        /// <param name="canEarlyOut">Reference to the early exit flag that may be modified</param>
+        /// <returns>True if status events should be dropped, false otherwise.</returns>
+        private bool ShouldDropStatusEvents(InputEventBuffer eventBuffer, ref bool canEarlyOut)
+        {
+            // If the game is not playing but we're sending all input events to the game,
+            // the buffer can just grow unbounded. So, in that case, set a flag to say we'd
+            // like to drop status events, and do not early out.
+            if (!gameIsPlaying && gameShouldGetInputRegardlessOfFocus && (eventBuffer.sizeInBytes > (100 * 1024)))
+            {
+                canEarlyOut = false;
+                return true;
+            }
+            return false;
+        }
+
+        /// <summary>
+        /// Determines if an event should be discarded based on timing or focus state.
+        /// </summary>
+        /// <param name="eventType">The type of event</param>
+        /// <param name="eventTime">The internal time of the current event</param>
+        /// <param name="updateType">The current update type</param>
+        /// <returns>True if the event should be discarded, false otherwise.</returns>
+        private bool ShouldDiscardEventInEditor(FourCC eventType, double eventTime, InputUpdateType updateType)
+        {
+            // Check if this is an event that occurred during edit mode transition
+            if (ShouldDiscardEditModeTransitionEvent(eventType, eventTime, updateType))
+                return true;
+
+            // Check if this is an out-of-focus event that should be discarded
+            if (ShouldDiscardOutOfFocusEvent(eventTime))
+                return true;
+
+            return false;
+        }
+
+        /// <summary>
+        /// In the editor, we discard all input events that occur in-between exiting edit mode and having
+        /// entered play mode as otherwise we'll spill a bunch of UI events that have occurred while the
+        /// UI was sort of neither in this mode nor in that mode. This would usually lead to the game receiving
+        /// an accumulation of spurious inputs right in one of its first updates.
+        ///
+        /// NOTE: There's a chance the solution here will prove inadequate on the long run. We may do things
+        ///       here such as throwing partial touches away and then letting the rest of a touch go through.
+        ///       Could be that ultimately we need to issue a full reset of all devices at the beginning of
+        ///       play mode in the editor.
+        /// </summary>
+        private bool ShouldDiscardEditModeTransitionEvent(FourCC eventType, double eventTime, InputUpdateType updateType)
+        {
+            return (eventType == StateEvent.Type || eventType == DeltaStateEvent.Type) &&
+                (updateType & InputUpdateType.Editor) == 0 &&
+                InputSystem.s_SystemObject.exitEditModeTime > 0 &&
+                eventTime >= InputSystem.s_SystemObject.exitEditModeTime &&
+                (eventTime < InputSystem.s_SystemObject.enterPlayModeTime ||
+                    InputSystem.s_SystemObject.enterPlayModeTime == 0);
+        }
+
+        /// <summary>
+        /// Checks if an event should be discarded because it occurred while out of focus, under specific settings.
+        /// </summary>
+        private bool ShouldDiscardOutOfFocusEvent(double eventTime)
+        {
+            // If we care about focus, check if the event occurred while out of focus based on its timestamp.
+            if (gameHasFocus && m_Settings.backgroundBehavior != InputSettings.BackgroundBehavior.IgnoreFocus)
+                return m_DiscardOutOfFocusEvents && eventTime < m_FocusRegainedTime;
+            return false;
+        }
+
+#endif
+
         bool AreMaximumEventBytesPerUpdateExceeded(uint totalEventBytesProcessed)
         {
             if (m_Settings.maxEventBytesPerUpdate > 0 &&