Fix Instance() method of Singleton classes

gazebo/common/FuelModelDatabase.cc

@@ -322,3 +322,16 @@ std::string FuelModelDatabase::CachedFilePath(const std::string &_uri)
 
   return path;
 }
+
+//////////////////////////////////////////////////
+FuelModelDatabase* FuelModelDatabase::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<FuelModelDatabase>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/common/FuelModelDatabase.hh

@@ -123,6 +123,9 @@ namespace gazebo
       /// \return Local path to the file
       public: std::string CachedFilePath(const std::string &_uri);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static FuelModelDatabase* Instance();
+
       /// \brief Private data.
       private: std::unique_ptr<FuelModelDatabasePrivate> dataPtr;
 

gazebo/common/MeshManager.cc

@@ -1394,5 +1394,18 @@ void MeshManager::ConvertPolylinesToVerticesAndEdges(
     }
   }
 }
+
+//////////////////////////////////////////////////
+MeshManager* MeshManager::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<MeshManager>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}
 }
 }

gazebo/common/MeshManager.hh

@@ -261,6 +261,9 @@ namespace gazebo
                       const ignition::math::Vector2d &_p,
                       double _tol);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static MeshManager* Instance();
+
       /// \brief Singleton implementation
       private: friend class SingletonT<MeshManager>;
 

gazebo/common/ModelDatabase.cc

@@ -683,3 +683,16 @@ std::string ModelDatabase::GetModelFile(const std::string &_uri)
 
   return result;
 }
+
+//////////////////////////////////////////////////
+ModelDatabase* ModelDatabase::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<ModelDatabase>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/common/ModelDatabase.hh

@@ -150,6 +150,9 @@ namespace gazebo
       /// no one else should use this function.
       private: bool UpdateModelCacheImpl();
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static ModelDatabase* Instance();
+
       /// \brief Private data.
       private: ModelDatabasePrivate *dataPtr;
 

gazebo/common/SingletonT.hh

@@ -29,11 +29,28 @@
 
 /// \class SingletonT SingletonT.hh common/common.hh
 /// \brief Singleton template class
+///
+/// This class can be used to simplify the implementation of singletons,
+/// i.e. classes that only have one instance. An important constraint to
+/// respect is that for each type `T`, the method SingletonT<T>::Instance
+/// should be instantiated only once. For this reason this method should
+/// be called only once for class, and only in a non-inline method not 
+/// defined in an header file. To ensure that the SingletonT<T>::Instance 
+/// method is not accidentally called in a inline method, or multiple times, 
+/// the method is marked as deprecated. To call it (after making sure that 
+/// you are calling it respecting the constraint given in documentation), 
+/// make sure to temporary suppress deprecation warnings before calling it,
+/// and suppress them again after the Instance method has been called.
+///
+/// See https://github.com/gazebosim/gazebo-classic/pull/3269 for further
+/// details on the use of this class.
+
+
 template <class T>
 class SingletonT
 {
   /// \brief Get an instance of the singleton
-  public: static T *Instance()
+  public: static T *Instance() GAZEBO_DEPRECATED(11.0)
           {
             return &GetInstance();
           }

gazebo/common/SystemPaths.cc

@@ -577,3 +577,16 @@ void SystemPaths::AddSearchPathSuffix(const std::string &_suffix)
 
   this->suffixPaths.push_back(s);
 }
+
+//////////////////////////////////////////////////
+SystemPaths* SystemPaths::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<SystemPaths>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/common/SystemPaths.hh

@@ -181,6 +181,9 @@ namespace gazebo
       private: void InsertUnique(const std::string &_path,
                                  std::list<std::string> &_list);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static SystemPaths* Instance();
+
       /// \brief Paths to installed gazebo media files
       private: std::list<std::string> gazeboPaths;
 

gazebo/gui/KeyEventHandler.cc

@@ -116,3 +116,16 @@ bool KeyEventHandler::Handle(const common::KeyEvent &_event,
   }
   return false;
 }
+
+//////////////////////////////////////////////////
+KeyEventHandler* KeyEventHandler::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<KeyEventHandler>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/gui/KeyEventHandler.hh

@@ -145,6 +145,9 @@ namespace gazebo
       private: bool Handle(const common::KeyEvent &_event,
                    std::list<Filter> &_list);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static KeyEventHandler* Instance();
+
       /// \brief This is a singleton class.
       private: friend class SingletonT<KeyEventHandler>;
 

gazebo/gui/ModelAlign.cc

@@ -362,3 +362,16 @@ void ModelAlign::SetHighlighted(const rendering::VisualPtr &_vis,
     }
   }
 }
+
+//////////////////////////////////////////////////
+ModelAlign* ModelAlign::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<ModelAlign>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/gui/ModelAlign.hh

@@ -97,6 +97,9 @@ namespace gazebo
       private: void SetHighlighted(const rendering::VisualPtr &_vis,
           const bool _highlight);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static ModelAlign* Instance();
+
       /// \brief This is a singleton class.
       private: friend class SingletonT<ModelAlign>;
 

gazebo/gui/ModelManipulator.cc

@@ -987,6 +987,19 @@ void ModelManipulator::OnKeyReleaseEvent(const common::KeyEvent &_event)
   this->dataPtr->keyEvent.key = 0;
 }
 
+//////////////////////////////////////////////////
+ModelManipulator* ModelManipulator::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<ModelManipulator>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}
+
 // Function migrated here from GLWidget.cc and commented out since it doesn't
 // seem like it's currently used. Kept here for future references
 /////////////////////////////////////////////////

gazebo/gui/ModelManipulator.hh

@@ -179,6 +179,9 @@ namespace gazebo
           const ignition::math::Vector3d &_axis,
           const ignition::math::Vector3d &_scale, const std::string &_geom);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static ModelManipulator* Instance();
+
       /// \brief This is a singleton class.
       private: friend class SingletonT<ModelManipulator>;
 

gazebo/gui/ModelSnap.cc

@@ -507,3 +507,16 @@ void ModelSnap::Update()
     this->dataPtr->selectedTriangleDirty = false;
   }
 }
+
+//////////////////////////////////////////////////
+ModelSnap* ModelSnap::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<ModelSnap>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/gui/ModelSnap.hh

@@ -111,6 +111,9 @@ namespace gazebo
       /// \brief Update the visual representation of the snap spot.
       private: void Update();
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static ModelSnap* Instance();
+
       /// \brief This is a singleton class.
       private: friend class SingletonT<ModelSnap>;
 

gazebo/gui/MouseEventHandler.cc

@@ -135,3 +135,16 @@ void MouseEventHandler::Handle(const common::MouseEvent &_event,
       break;
   }
 }
+
+//////////////////////////////////////////////////
+MouseEventHandler* MouseEventHandler::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<MouseEventHandler>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/gui/MouseEventHandler.hh

@@ -156,6 +156,9 @@ namespace gazebo
       private: void Handle(const common::MouseEvent &_event,
                    std::list<Filter> &_list);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static MouseEventHandler* Instance();
+
       /// \brief List of mouse press filters.
       private: std::list<Filter> pressFilters;
 

gazebo/gui/plot/PlotManager.cc

@@ -190,3 +190,16 @@ std::string PlotManager::HumanReadableName(const std::string &_uri) const
 
   return label;
 }
+
+//////////////////////////////////////////////////
+PlotManager* PlotManager::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<PlotManager>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/gui/plot/PlotManager.hh

@@ -87,6 +87,9 @@ namespace gazebo
       /// \return Human readable name
       public: std::string HumanReadableName(const std::string &_uri) const;
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static PlotManager* Instance();
+
       /// \brief This is a singleton class.
       private: friend class SingletonT<PlotManager>;
 

gazebo/gui/plot/TopicCurveHandler.cc

@@ -55,6 +55,9 @@ namespace gazebo
       /// \param[in] _msg WorldStats msg.
       public: void OnStats(ConstWorldStatisticsPtr &_msg);
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static TopicTime* Instance();
+
       /// \brief Node for communications.
       private: transport::NodePtr node;
 
@@ -168,6 +171,19 @@ void TopicTime::OnStats(ConstWorldStatisticsPtr &_msg)
   this->lastSimTime = msgs::Convert(t);
 }
 
+//////////////////////////////////////////////////
+TopicTime* TopicTime::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<TopicTime>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}
+
 /////////////////////////////////////////////////
 common::Time TopicTime::LastSimTime()
 {

gazebo/rendering/RTShaderSystem.cc

@@ -810,3 +810,16 @@ void RTShaderSystem::UpdateShadows(ScenePtr _scene)
   sceneMgr->setShadowTextureCasterMaterial(_scene->ShadowCasterMaterialName());
 #endif
 }
+
+//////////////////////////////////////////////////
+RTShaderSystem* RTShaderSystem::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<RTShaderSystem>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/rendering/RTShaderSystem.hh

@@ -187,6 +187,9 @@ namespace gazebo
       /// \brief Re-apply shadows. Call this if a shadow paramenter is changed.
       private: void ReapplyShadows();
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static RTShaderSystem* Instance();
+
       /// \brief Make the RTShader system a singleton.
       private: friend class SingletonT<RTShaderSystem>;
 

gazebo/rendering/RenderEngine.cc

@@ -883,3 +883,16 @@ Ogre::OverlaySystem *RenderEngine::OverlaySystem() const
   return this->dataPtr->overlaySystem;
 }
 #endif
+
+//////////////////////////////////////////////////
+RenderEngine* RenderEngine::Instance()
+{
+#ifndef _WIN32
+  #pragma GCC diagnostic push
+  #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+#endif
+  return SingletonT<RenderEngine>::Instance();
+#ifndef _WIN32
+  #pragma GCC diagnostic pop
+#endif
+}

gazebo/rendering/RenderEngine.hh

@@ -168,6 +168,9 @@ namespace gazebo
       /// \brief Check the rendering capabilities of the system.
       private: void CheckSystemCapabilities();
 
+      /// \brief Returns a pointer to the unique (static) instance
+      public: static RenderEngine* Instance();
+
       /// \brief ID for a dummy window. Used for gui-less operation
       protected: uint64_t dummyWindowId;