Gui: Accumulate orientation for NaviCube flat button animations

src/Gui/NaviCube.cpp

@@ -54,6 +54,7 @@
 #include "Command.h"
 #include "Action.h"
 #include "MainWindow.h"
+#include "Navigation/NavigationAnimation.h"
 #include "View3DInventorViewer.h"
 #include "View3DInventor.h"
 #include "ViewParams.h"
@@ -63,10 +64,6 @@ using namespace Eigen;
 using namespace std;
 using namespace Gui;
 
-
-
-
-
 class NaviCubeImplementation {
 public:
     explicit NaviCubeImplementation(Gui::View3DInventorViewer*);
@@ -206,6 +203,9 @@ private:
     map<PickId, LabelTexture> m_LabelTextures;
 
     QMenu* m_Menu;
+
+    std::shared_ptr<NavigationAnimation> m_flatButtonAnimation;
+    SbRotation m_flatButtonTargetOrientation;
 };
 
 int NaviCubeImplementation::m_CubeWidgetSize = 132;
@@ -1102,7 +1102,17 @@ bool NaviCubeImplementation::mouseReleased(short x, short y)
             else {
                 rotation.scaleAngle(rotStepAngle);
             }
-            m_View3DInventorViewer->setCameraOrientation(rotation * m_View3DInventorViewer->getCameraOrientation());
+
+            // If the previous flat button animation is still active then apply the rotation to the
+            // previous target orientation, otherwise apply the rotation to the current camera orientation
+            if (m_flatButtonAnimation != nullptr && m_flatButtonAnimation->state() == QAbstractAnimation::Running) {
+                m_flatButtonTargetOrientation = rotation * m_flatButtonTargetOrientation;
+            }
+            else {
+                m_flatButtonTargetOrientation = rotation * m_View3DInventorViewer->getCameraOrientation();
+            }
+
+            m_flatButtonAnimation = m_View3DInventorViewer->setCameraOrientation(m_flatButtonTargetOrientation);
         }
         else {
             return false;

src/Gui/Navigation/NavigationAnimation.cpp

@@ -33,7 +33,7 @@ NavigationAnimation::NavigationAnimation(NavigationStyle* navigation)
 
 void NavigationAnimation::updateCurrentValue(const QVariant& value)
 {
-    if (state() == QAbstractAnimation::State::Stopped) {
+    if (state() != QAbstractAnimation::State::Running) {
         return;
     }
     update(value);

src/Gui/Navigation/NavigationAnimation.h

@@ -37,6 +37,7 @@ class GuiExport NavigationAnimation : protected QVariantAnimation
     Q_OBJECT
 public:
     explicit NavigationAnimation(NavigationStyle* navigation);
+    using QVariantAnimation::state;
 
 Q_SIGNALS:
     void interrupted();