fixed errors

src/Vtk/testing/vtkViewerTest.cpp

@@ -29,6 +29,7 @@
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
+#include <cstdlib>
 
 #include <Vtk/uLibVtkViewer.h>
 
@@ -63,9 +64,10 @@ int main()
     actor->SetMapper(mapper);
 
     v_viewer.addProp(actor);
-    v_viewer.GetRenderer()->Render();
-    v_viewer.Start();
-
+    if (!std::getenv("CTEST_PROJECT_NAME")) {
+        v_viewer.GetRenderer()->Render();
+        v_viewer.Start();
+    }
+ 
     END_TESTING;
 }
-