prevent losing Rug texture on open/close window

basegraph.cpp

@@ -600,6 +600,10 @@ EX void resetGL() {
   matched_programs.clear();
   glhr::current_glprogram = nullptr;
   ray::reset_raycaster();
+  if(rug::rugged) {
+    rug::close();
+    rug::reopen();
+    }
   }
 
 #endif