VisualProcessor now a template base, more tweaking needed

src/util/ThreadQueue.h

@@ -211,6 +211,15 @@ public:
         return m_queue.empty();
     }
 
+    /**
+     *  Check if the queue is empty.
+     * \return true if queue is empty.
+     */
+    bool full() const {
+        std::lock_guard < std::mutex > lock(m_mutex);
+        return m_queue.size() >= m_max_num_items;
+    }
+
     /**
      *  Remove any items in the queue.
      */