Follow character option (#5538)

* Follow character option

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

* CR feedback

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

Gems/AtomLyIntegration/EMotionFXAtom/Code/Tools/EMStudio/AnimViewportRenderer.cpp

@@ -178,20 +178,13 @@ namespace EMStudio
         if (!m_actorEntities.empty())
         {
             // Find the actor instance and calculate the center from aabb.
-            AZ::Vector3 actorCenter = AZ::Vector3::CreateZero();
             EMotionFX::Integration::ActorComponent* actorComponent =
                 m_actorEntities[0]->FindComponent<EMotionFX::Integration::ActorComponent>();
             EMotionFX::ActorInstance* actorInstance = actorComponent->GetActorInstance();
             if (actorInstance)
             {
-                actorCenter += actorInstance->GetAabb().GetCenter();
+                result = actorInstance->GetAabb().GetCenter();
             }
-            
-            // Just return the position of the first entity.
-            AZ::Transform worldTransform;
-            AZ::TransformBus::EventResult(worldTransform, m_actorEntities[0]->GetId(), &AZ::TransformBus::Events::GetWorldTM);
-            result = worldTransform.GetTranslation();
-            result += actorCenter;
         }
 
         return result;

Gems/AtomLyIntegration/EMotionFXAtom/Code/Tools/EMStudio/AnimViewportRequestBus.h

@@ -36,6 +36,9 @@ namespace EMStudio
         //! Set the camera view mode.
         virtual void SetCameraViewMode(CameraViewMode mode) = 0;
 
+        //! Set the camera follow up
+        virtual void SetFollowCharacter(bool follow) = 0;
+
         //! Toggle render option flag
         virtual void ToggleRenderFlag(EMotionFX::ActorRenderFlag flag) = 0;
     };

Gems/AtomLyIntegration/EMotionFXAtom/Code/Tools/EMStudio/AnimViewportToolBar.cpp

@@ -87,6 +87,19 @@ namespace EMStudio
                     // Send the reset camera event.
                     AnimViewportRequestBus::Broadcast(&AnimViewportRequestBus::Events::ResetCamera);
                 });
+
+            cameraMenu->addSeparator();
+            m_followCharacterAction = cameraMenu->addAction("Follow Character");
+            m_followCharacterAction->setCheckable(true);
+            m_followCharacterAction->setChecked(false);
+            connect(m_followCharacterAction, &QAction::triggered, this,
+                [this]()
+                {
+                    AnimViewportRequestBus::Broadcast(
+                        &AnimViewportRequestBus::Events::SetFollowCharacter, m_followCharacterAction->isChecked());
+                    ;
+                });
+
             cameraButton->setMenu(cameraMenu);
             cameraButton->setText("Camera Option");
             cameraButton->setPopupMode(QToolButton::InstantPopup);

Gems/AtomLyIntegration/EMotionFXAtom/Code/Tools/EMStudio/AnimViewportToolBar.h

@@ -31,5 +31,6 @@ namespace EMStudio
             QMenu* menu, const char* menuEntryName, uint32_t actionIndex, bool visible = true, char* iconFileName = nullptr);
 
         QAction* m_actions[EMotionFX::ActorRenderFlag::NUM_RENDERFLAGS] = { nullptr };
+        QAction* m_followCharacterAction = nullptr;
     };
 }

Gems/AtomLyIntegration/EMotionFXAtom/Code/Tools/EMStudio/AnimViewportWidget.cpp

@@ -147,36 +147,43 @@ namespace EMStudio
         switch (mode)
         {
         case CameraViewMode::FRONT:
-            cameraPosition.Set(0.0f, CameraDistance, targetPosition.GetZ());
+            cameraPosition.Set(targetPosition.GetX(), targetPosition.GetY() + CameraDistance, targetPosition.GetZ());
             break;
         case CameraViewMode::BACK:
-            cameraPosition.Set(0.0f, -CameraDistance, targetPosition.GetZ());
+            cameraPosition.Set(targetPosition.GetX(), targetPosition.GetY() - CameraDistance, targetPosition.GetZ());
             break;
         case CameraViewMode::TOP:
-            cameraPosition.Set(0.0f, 0.0f, CameraDistance + targetPosition.GetZ());
+            cameraPosition.Set(targetPosition.GetX(), targetPosition.GetY(), CameraDistance + targetPosition.GetZ());
             break;
         case CameraViewMode::BOTTOM:
-            cameraPosition.Set(0.0f, 0.0f, -CameraDistance + targetPosition.GetZ());
+            cameraPosition.Set(targetPosition.GetX(), targetPosition.GetY(), -CameraDistance + targetPosition.GetZ());
             break;
         case CameraViewMode::LEFT:
-            cameraPosition.Set(-CameraDistance, 0.0f, targetPosition.GetZ());
+            cameraPosition.Set(targetPosition.GetX() - CameraDistance, targetPosition.GetY(), targetPosition.GetZ());
             break;
         case CameraViewMode::RIGHT:
-            cameraPosition.Set(CameraDistance, 0.0f, targetPosition.GetZ());
+            cameraPosition.Set(targetPosition.GetX() + CameraDistance, targetPosition.GetY(), targetPosition.GetZ());
             break;
         case CameraViewMode::DEFAULT:
             // The default view mode is looking from the top left of the character.
-            cameraPosition.Set(-CameraDistance, CameraDistance, CameraDistance + targetPosition.GetZ());
+            cameraPosition.Set(
+                targetPosition.GetX() - CameraDistance, targetPosition.GetY() + CameraDistance, targetPosition.GetZ() + CameraDistance);
             break;
         }
         GetViewportContext()->SetCameraTransform(AZ::Transform::CreateLookAt(cameraPosition, targetPosition));
     }
 
+    void AnimViewportWidget::SetFollowCharacter(bool follow)
+    {
+        m_followCharacter = follow;
+    }
+
     void AnimViewportWidget::OnTick(float deltaTime, AZ::ScriptTimePoint time)
     {
         RenderViewportWidget::OnTick(deltaTime, time);
         CalculateCameraProjection();
         RenderCustomPluginData();
+        FollowCharacter();
     }
 
     void AnimViewportWidget::CalculateCameraProjection()
@@ -205,6 +212,20 @@ namespace EMStudio
         }
     }
 
+    void AnimViewportWidget::FollowCharacter()
+    {
+        if (m_followCharacter)
+        {
+            // When follow charater move is enabled, we are adding the delta of the character movement to the camera per frame.
+            AZ::Vector3 camPos = GetViewportContext()->GetCameraTransform().GetTranslation();
+            camPos += m_renderer->GetCharacterCenter() - m_prevCharacterPos;
+            AZ::Transform newCamTransform = GetViewportContext()->GetCameraTransform();
+            newCamTransform.SetTranslation(camPos);
+            GetViewportContext()->SetCameraTransform(newCamTransform);
+        }
+        m_prevCharacterPos = m_renderer->GetCharacterCenter();
+    }
+
     void AnimViewportWidget::ToggleRenderFlag(EMotionFX::ActorRenderFlag flag)
     {
         m_renderFlags[flag] = !m_renderFlags[flag];

Gems/AtomLyIntegration/EMotionFXAtom/Code/Tools/EMStudio/AnimViewportWidget.h

@@ -38,6 +38,7 @@ namespace EMStudio
 
         void CalculateCameraProjection();
         void RenderCustomPluginData();
+        void FollowCharacter();
 
         void SetupCameras();
         void SetupCameraController();
@@ -48,6 +49,7 @@ namespace EMStudio
         // AnimViewportRequestBus::Handler overrides
         void ResetCamera();
         void SetCameraViewMode(CameraViewMode mode);
+        void SetFollowCharacter(bool follow);
         void ToggleRenderFlag(EMotionFX::ActorRenderFlag flag);
 
         // ViewportPluginRequestBus::Handler overrides
@@ -61,5 +63,7 @@ namespace EMStudio
         AZStd::shared_ptr<AzFramework::TranslateCameraInput> m_translateCamera;
         AZStd::shared_ptr<AzFramework::OrbitDollyScrollCameraInput> m_orbitDollyScrollCamera;
         EMotionFX::ActorRenderFlagBitset m_renderFlags;
+        bool m_followCharacter = false;
+        AZ::Vector3 m_prevCharacterPos;
     };
 }