Address a few more review things

Signed-off-by: nvsickle <nvsickle@amazon.com>

Code/Editor/EditorViewportWidget.cpp

@@ -714,7 +714,7 @@ void EditorViewportWidget::OnEditorNotifyEvent(EEditorNotifyEvent event)
 
         if (m_renderViewport)
         {
-            m_renderViewport->GetControllerList()->SetEnabled(false);
+            m_renderViewport->SetInputProcessingEnabled(false);
         }
     }
     break;
@@ -738,7 +738,7 @@ void EditorViewportWidget::OnEditorNotifyEvent(EEditorNotifyEvent event)
 
         if (m_renderViewport)
         {
-            m_renderViewport->GetControllerList()->SetEnabled(true);
+            m_renderViewport->SetInputProcessingEnabled(true);
         }
         break;
 

Code/Framework/AzFramework/AzFramework/Viewport/CameraInput.cpp

@@ -747,7 +747,7 @@ namespace AzFramework
                 return button == inputChannelId;
             });
 
-        // Accept active mouse channel updates, inactive movement channels will just have a 0 delta.
+        // accept active mouse channel updates, inactive movement channels will just have a 0 delta
         if (inputChannel.IsActive())
         {
             if (inputChannelId == InputDeviceMouse::Movement::X)
@@ -763,6 +763,7 @@ namespace AzFramework
                 return ScrollEvent{ inputChannel.GetValue() };
             }
         }
+
         if (wasMouseButton || InputDeviceKeyboard::IsKeyboardDevice(inputDeviceId))
         {
             return DiscreteInputEvent{ inputChannelId, inputChannel.GetState() };

Code/Framework/AzToolsFramework/AzToolsFramework/Input/QtEventToAzInputManager.cpp

@@ -200,8 +200,24 @@ namespace AzToolsFramework
             deviceId.GetNameCrc32() == AzFramework::InputDeviceKeyboard::Id.GetNameCrc32();
     }
 
+    void QtEventToAzInputMapper::SetEnabled(bool enabled)
+    {
+        m_enabled = enabled;
+        if (!enabled)
+        {
+            // Send an internal focus change event to reset our input state to fresh if we're disabled.
+            HandleFocusChange(nullptr);
+        }
+    }
+
     bool QtEventToAzInputMapper::eventFilter(QObject* object, QEvent* event)
     {
+        // Abort if processing isn't enabled.
+        if (!m_enabled)
+        {
+            return false;
+        }
+
         // Because there's no "end" to mouse movement and wheel events, we reset mouse movement channels that have been opened
         // during the next processed non-mouse event.
         if (m_mouseChannelsNeedUpdate && event->type() != QEvent::Type::MouseMove && event->type() != QEvent::Type::Wheel)
@@ -268,14 +284,14 @@ namespace AzToolsFramework
     {
         auto systemCursorChannel =
             GetInputChannel<AzFramework::InputChannelDeltaWithSharedPosition2D>(AzFramework::InputDeviceMouse::SystemCursorPosition);
-        auto cursorZChannel =
+        auto mouseWheelChannel =
             GetInputChannel<AzFramework::InputChannelDeltaWithSharedPosition2D>(AzFramework::InputDeviceMouse::Movement::Z);
 
         systemCursorChannel->ProcessRawInputEvent(m_cursorPosition->m_normalizedPositionDelta.GetLength());
-        cursorZChannel->ProcessRawInputEvent(0.f);
+        mouseWheelChannel->ProcessRawInputEvent(0.f);
 
         NotifyUpdateChannelIfNotIdle(systemCursorChannel, nullptr);
-        NotifyUpdateChannelIfNotIdle(cursorZChannel, nullptr);
+        NotifyUpdateChannelIfNotIdle(mouseWheelChannel, nullptr);
     }
 
     void QtEventToAzInputMapper::HandleMouseButtonEvent(QMouseEvent* mouseEvent)

Code/Framework/AzToolsFramework/AzToolsFramework/Input/QtEventToAzInputManager.h

@@ -44,6 +44,9 @@ namespace AzToolsFramework
         //! \returns true if the channel is handled by MapQtEventToAzInput.
         bool HandlesInputEvent(const AzFramework::InputChannel& channel) const;
 
+        //! Sets whether or not this input mapper should be updating its input channels from Qt events.
+        void SetEnabled(bool enabled);
+
         // QObject overrides...
         bool eventFilter(QObject* object, QEvent* event) override;
 
@@ -64,7 +67,7 @@ namespace AzToolsFramework
             {
                 return static_cast<TInputChannel*>(channelIt->second);
             }
-            return {};
+            return nullptr;
         }
 
         // Adds channels from the specified channel container to our input channel ID -> input channel lookup table.
@@ -139,6 +142,8 @@ namespace AzToolsFramework
         QWidget* m_sourceWidget;
         // Flags when mouse movement channels have been opened and may need to be closed (as there are no movement ended events).
         bool m_mouseChannelsNeedUpdate = false;
+        // Flags whether or not Qt events should currently be processed.
+        bool m_enabled = true;
 
         // Our viewport-specific AZ devices. We control their internal input channel states.
         AZStd::unique_ptr<EditorQtMouseDevice> m_mouseDevice;

Gems/Atom/Tools/AtomToolsFramework/Code/Include/AtomToolsFramework/Viewport/RenderViewportWidget.h

@@ -82,6 +82,12 @@ namespace AtomToolsFramework
         //! Gets the default camera that's been automatically registered to our ViewportContext.
         AZ::RPI::ViewPtr GetDefaultCamera();
         AZ::RPI::ConstViewPtr GetDefaultCamera() const;
+        //! Sets whether or not input processing is enabled for this RenderViewportWidget.
+        //! While input processing is enabled, synthetic input events may appear in OnInputChannelEventFiltered
+        //! due to internal viewport input mapping via QtEventToAzInputMapper, so it may be desirable to disable
+        //! camera controller input processing wholesale to avoid competing input messages.
+        //! Input processing is enabled by default.
+        void SetInputProcessingEnabled(bool enabled);
 
         // AzToolsFramework::ViewportInteraction::ViewportInteractionRequestBus::Handler ...
         AzFramework::CameraState GetCameraState() override;

Gems/Atom/Tools/AtomToolsFramework/Code/Source/Viewport/RenderViewportWidget.cpp

@@ -299,6 +299,12 @@ namespace AtomToolsFramework
         }
     }
 
+    void RenderViewportWidget::SetInputProcessingEnabled(bool enabled)
+    {
+        m_inputChannelMapper->SetEnabled(enabled);
+        m_controllerList->SetEnabled(enabled);
+    }
+
     AzFramework::CameraState RenderViewportWidget::GetCameraState()
     {
         AZ::RPI::ViewPtr currentView = m_viewportContext->GetDefaultView();