Fix game mode camera components not working in-Editor

Ensures RPI::View updates always make it back to the ViewportContext, even if you talk directly to the View

Gems/Atom/RPI/Code/Include/Atom/RPI.Public/View.h

@@ -118,6 +118,12 @@ namespace AZ
             //! Update View's SRG values and compile. This should only be called once per frame before execute command lists.
             void UpdateSrg();
 
+            using MatrixChangedEvent = AZ::Event<const AZ::Matrix4x4&>;
+            //! Notifies consumers when the world to view matrix has changed.
+            void ConnectWorldToViewMatrixChangedHandler(MatrixChangedEvent::Handler& handler);
+            //! Notifies consumers when the world to clip matrix has changed.
+            void ConnectWorldToClipMatrixChangedHandler(MatrixChangedEvent::Handler& handler);
+
         private:
             View() = delete;
             View(const AZ::Name& name, UsageFlags usage);
@@ -182,6 +188,9 @@ namespace AZ
             // view class doesn't contain subroutines called at the end of each frame
             bool m_worldToClipMatrixChanged = true;
             bool m_worldToClipPrevMatrixNeedsUpdate = false;
+
+            MatrixChangedEvent m_oWworldToClipMatrixChange;
+            MatrixChangedEvent m_onWorldToViewMatrixChange;
         };
 
         AZ_DEFINE_ENUM_BITWISE_OPERATORS(View::UsageFlags);

Gems/Atom/RPI/Code/Include/Atom/RPI.Public/ViewportContext.h

@@ -125,7 +125,9 @@ namespace AZ
             AzFramework::WindowSize m_viewportSize;
             SizeChangedEvent m_sizeChangedEvent;
             MatrixChangedEvent m_viewMatrixChangedEvent;
+            MatrixChangedEvent::Handler m_onViewMatrixChangedHandler;
             MatrixChangedEvent m_projectionMatrixChangedEvent;
+            MatrixChangedEvent::Handler m_onProjectionMatrixChangedHandler;
             SceneChangedEvent m_sceneChangedEvent;
             ViewportContextManager* m_manager;
             RenderPipelinePtr m_currentPipeline;

Gems/Atom/RPI/Code/Source/RPI.Public/View.cpp

@@ -104,6 +104,9 @@ namespace AZ
             m_worldToClipMatrix = m_viewToClipMatrix * m_worldToViewMatrix;
             m_worldToClipMatrixChanged = true;
 
+            m_onWorldToViewMatrixChange.Signal(m_worldToViewMatrix);
+            m_oWworldToClipMatrixChange.Signal(m_worldToClipMatrix);
+
             InvalidateSrg();
         }
 
@@ -132,6 +135,9 @@ namespace AZ
             m_clipToWorldMatrix = m_viewToWorldMatrix * m_clipToViewMatrix;
             m_worldToClipMatrixChanged = true;
 
+            m_onWorldToViewMatrixChange.Signal(m_worldToViewMatrix);
+            m_oWworldToClipMatrixChange.Signal(m_worldToClipMatrix);
+
             InvalidateSrg();
         }        
 
@@ -166,6 +172,8 @@ namespace AZ
             m_unprojectionConstants.SetZ(float(-tanHalfFovX));
             m_unprojectionConstants.SetW(float(tanHalfFovY));
 
+            m_oWworldToClipMatrixChange.Signal(m_worldToClipMatrix);
+
             InvalidateSrg();
         }
 
@@ -225,6 +233,16 @@ namespace AZ
             passWithDrawListTag->SortDrawList(drawList);
         }
 
+        void View::ConnectWorldToViewMatrixChangedHandler(View::MatrixChangedEvent::Handler& handler)
+        {
+            handler.Connect(m_onWorldToViewMatrixChange);
+        }
+
+        void View::ConnectWorldToClipMatrixChangedHandler(View::MatrixChangedEvent::Handler& handler)
+        {
+            handler.Connect(m_oWworldToClipMatrixChange);
+        }
+
         // [GFX TODO] This function needs unit tests and might need to be reworked 
         RHI::DrawItemSortKey View::GetSortKeyForPosition(const Vector3& positionInWorld) const
         {

Gems/Atom/RPI/Code/Source/RPI.Public/ViewportContext.cpp

@@ -34,8 +34,16 @@ namespace AZ
                 &AzFramework::WindowRequestBus::Events::GetClientAreaSize);
             AzFramework::WindowNotificationBus::Handler::BusConnect(nativeWindow);
 
-            SetRenderScene(renderScene);
-        }
+            m_onProjectionMatrixChangedHandler = ViewportContext::MatrixChangedEvent::Handler([this](const AZ::Matrix4x4& matrix)
+            {
+                m_projectionMatrixChangedEvent.Signal(matrix);
+            });
+            m_onViewMatrixChangedHandler = ViewportContext::MatrixChangedEvent::Handler([this](const AZ::Matrix4x4& matrix)
+            {
+                m_projectionMatrixChangedEvent.Signal(matrix);
+            });
+
+            SetRenderScene(renderScene);        }
 
         ViewportContext::~ViewportContext()
         {
@@ -175,7 +183,6 @@ namespace AZ
         void ViewportContext::SetCameraProjectionMatrix(const AZ::Matrix4x4& matrix)
         {
             GetDefaultView()->SetViewToClipMatrix(matrix);
-            m_projectionMatrixChangedEvent.Signal(matrix);
         }
 
         AZ::Transform ViewportContext::GetCameraTransform() const
@@ -192,18 +199,23 @@ namespace AZ
         {
             const auto view = GetDefaultView();
             view->SetCameraTransform(AZ::Matrix3x4::CreateFromTransform(transform.GetOrthogonalized()));
-            m_viewMatrixChangedEvent.Signal(view->GetWorldToViewMatrix());
         }
 
         void ViewportContext::SetDefaultView(ViewPtr view)
         {
             if (m_defaultView != view)
             {
+                m_onProjectionMatrixChangedHandler.Disconnect();
+                m_onViewMatrixChangedHandler.Disconnect();
+
                 m_defaultView = view;
                 UpdatePipelineView();
 
                 m_viewMatrixChangedEvent.Signal(view->GetWorldToViewMatrix());
                 m_projectionMatrixChangedEvent.Signal(view->GetViewToClipMatrix());
+
+                view->ConnectWorldToViewMatrixChangedHandler(m_onViewMatrixChangedHandler);
+                view->ConnectWorldToClipMatrixChangedHandler(m_onProjectionMatrixChangedHandler);
             }
         }