Allow disabling tips if empty (or no) tips.xml

src/guiengine/engine.cpp

@@ -1432,7 +1432,7 @@ namespace GUIEngine
     void renderLoading(bool clearIcons, bool launching, bool update_tips)
     {
 #ifndef SERVER_ONLY
-        if (update_tips)
+        if (!TipsManager::get()->isEmpty() && update_tips)
         {
             core::stringw tip = TipsManager::get()->getTip("general");
             //I18N: Tip shown in gui for giving player hints

src/states_screens/race_result_gui.cpp

@@ -189,7 +189,8 @@ void RaceResultGUI::init()
     }
 
 #ifndef SERVER_ONLY
-    if (!human_win && !NetworkConfig::get()->isNetworking())
+    if (!human_win && !NetworkConfig::get()->isNetworking() &&
+        !TipsManager::get()->isEmpty())
     {
         std::string tipset = "race";
         if (RaceManager::get()->isSoccerMode())

src/tips/tips_manager.cpp

@@ -36,7 +36,11 @@ TipsManager* TipsManager::m_tips_manager = NULL;
 TipsManager::TipsManager()
 {
     const std::string file_name = file_manager->getAsset("tips.xml");
+    if (file_name.empty())
+        return;
     const XMLNode *root = file_manager->createXMLTree(file_name);
+    if (!root)
+        return;
     unsigned int num_nodes = root->getNumNodes();
 
     for (unsigned int i = 0; i < num_nodes; i++)

src/tips/tips_manager.hpp

@@ -70,6 +70,8 @@ public:
     /** Get a tip by ID. */
     const irr::core::stringw& getTip(const std::string& id) const;
     // ------------------------------------------------------------------------
+    bool isEmpty() const { return m_all_tip_sets.empty(); }
+    // ------------------------------------------------------------------------
 };   // class TipsManager
 
 #endif