added mutex and std::map to keep track of tasks in progress; Scene waits for their completion

git-svn-id: svn://anubis/fart/trunk@232 7f9b0f55-74a9-4bce-be96-3c2cd072584d

main/Scene.cc

@@ -160,7 +160,13 @@ void Scene::render()
         {
             /* work on tasks in this thread until there are no more */
             taskLoop();
-            /* TODO: wait until all data has arrived */
+            /* TODO: change wait condition */
+            for (;;)
+            {
+                if (m_distrib.getNumTasksInProgress() == 0)
+                    break;
+                usleep(100000);
+            }
         }
 
         if (m_verbose)