Enable toggling use of doublebuffering for camera and time

include/openspace/util/camera.h

@@ -121,7 +121,23 @@ namespace openspace {
 
         // Synchronization
         void serialize(SyncBuffer* syncBuffer);
-        void deserialize(SyncBuffer* syncBuffer);
+
+        /**
+        * Updates camera variables from data in syncbuffer. If \param useDoubleBuffering is 
+        * false, values will be written directly into the camera state, overwriting any
+        * previous values.
+        * If \param useDoubleBuffering is true, values will be written and stored in local
+        * copies, keeping the state unchanged until <code>updateDoubleBuffer</code> has
+        * been called.
+        */
+        void deserialize(SyncBuffer* syncBuffer, bool useDoubleBuffering);
+
+        /**
+        * This method should be called from the SGCT postSynchronization stage if and only
+        * if method <code>deserialize</code> has previously been called with the argument
+        * useDoubleBuffering set to true.
+        */
+        void updateDoubleBuffer();
         
         void serialize(std::ostream& os) const;
         void deserialize(std::istream& is);
@@ -176,7 +192,6 @@ namespace openspace {
         [[deprecated("Replaced by Camera::SgctInternal::viewProjectionMatrix()")]]
         const glm::mat4& viewProjectionMatrix() const;
 
-        void updateDoubleBuffer();
 
     private:
         struct SyncData {

include/openspace/util/time.h

@@ -181,7 +181,16 @@ public:
 
     void serialize(SyncBuffer* syncBuffer);
 
-    void deserialize(SyncBuffer* syncBuffer);
+
+    /**
+    * Updates time variables from data in syncbuffer. If \param useDoubleBuffering is
+    * false, values will be written directly into the time state, overwriting any
+    * previous values.
+    * If \param useDoubleBuffering is true, values will be written and stored in local
+    * copies, keeping the time state unchanged until <code>updateDoubleBuffer</code> has
+    * been called.
+    */
+    void deserialize(SyncBuffer* syncBuffer, bool useDoubleBuffering);
 
     bool timeJumped() const;
 
@@ -189,6 +198,11 @@ public:
     
     bool paused() const;
 
+    /**
+    * This method should be called from the SGCT postSynchronization stage if and only 
+    * if method <code>deserialize</code> has previously been called with the argument 
+    * useDoubleBuffering set to true.
+    */
     void updateDoubleBuffer();
 
     /**