UPBGE: Fix reference counting of module items.

The item passed to PyDict_SetItemString will be incref, so if the item
is constructed in the current scope and not stored in an external data,
the item must be decref.

These rules are applied to KX_PythonInit.cpp and remove the usage of
PyDict_Clear in LA_Launcher.

source/gameengine/Ketsji/KX_PythonInit.cpp

@@ -1452,6 +1452,7 @@ PyMODINIT_FUNC initGameLogicPythonBinding()
 		PyList_SET_ITEM(joylist, i, Py_None);
 	}
 	PyDict_SetItemString(d, "joysticks", joylist);
+	Py_DECREF(joylist);
 
 	ErrorObject = PyUnicode_FromString("GameLogic.error");
 	PyDict_SetItemString(d, "error", ErrorObject);
@@ -2057,7 +2058,9 @@ void initGamePlayerPythonScripting(Main *maggie, int argc, char** argv)
 	}
 #endif
 
-	PyDict_SetItemString(PyImport_GetModuleDict(), "bge", initBGE());
+	PyObject *mod = initBGE();
+	PyDict_SetItemString(PyImport_GetModuleDict(), "bge", mod);
+	Py_DECREF(mod);
 
 	first_time = false;
 
@@ -2109,7 +2112,9 @@ void initGamePythonScripting(Main *maggie)
 	}
 #endif
 
-	PyDict_SetItemString(PyImport_GetModuleDict(), "bge", initBGE());
+	PyObject *mod = initBGE();
+	PyDict_SetItemString(PyImport_GetModuleDict(), "bge", mod);
+	Py_DECREF(mod);
 
 	EXP_PyObjectPlus::NullDeprecationWarning();
 }
@@ -2137,8 +2142,7 @@ void exitGamePythonScripting()
 
 /* similar to the above functions except it sets up the namespace
  * and other more general things */
-void setupGamePython(KX_KetsjiEngine* ketsjiengine, Main *blenderdata,
-                     PyObject *pyGlobalDict, PyObject **gameLogic, int argc, char** argv)
+void setupGamePython(KX_KetsjiEngine* ketsjiengine, Main *blenderdata, PyObject *pyGlobalDict, int argc, char** argv)
 {
 	PyObject *modules;
 
@@ -2149,10 +2153,11 @@ void setupGamePython(KX_KetsjiEngine* ketsjiengine, Main *blenderdata,
 
 	modules = PyImport_GetModuleDict();
 
-	*gameLogic = PyDict_GetItemString(modules, "GameLogic");
+	PyObject *gameLogic = PyDict_GetItemString(modules, "GameLogic");
 	/* is set in initGameLogicPythonBinding so only set here if we want it to persist between scenes */
 	if (pyGlobalDict)
-		PyDict_SetItemString(PyModule_GetDict(*gameLogic), "globalDict", pyGlobalDict); // Same as importing the module.z
+		PyDict_SetItemString(PyModule_GetDict(gameLogic), "globalDict", pyGlobalDict); // Same as importing the module.z
+	Py_DECREF(gameLogic);
 }
 
 void createPythonConsole()

source/gameengine/Ketsji/KX_PythonInit.h

@@ -54,8 +54,7 @@ void appendPythonPath(const std::string& path);
 
 void exitGamePlayerPythonScripting();
 void exitGamePythonScripting();
-void setupGamePython(KX_KetsjiEngine *ketsjiengine, Main *blenderdata,
-                     PyObject *pyGlobalDict, PyObject **gameLogic, int argc, char **argv);
+void setupGamePython(KX_KetsjiEngine *ketsjiengine, Main *blenderdata, PyObject *pyGlobalDict, int argc, char **argv);
 std::string pathGamePythonConfig();
 void saveGamePythonConfig();
 void loadGamePythonConfig();

source/gameengine/Launcher/LA_Launcher.cpp

@@ -96,7 +96,6 @@ LA_Launcher::LA_Launcher(GHOST_ISystem *system, Main *maggie, Scene *scene, Glob
 	m_converter(nullptr),
 #ifdef WITH_PYTHON
 	m_globalDict(nullptr),
-	m_gameLogic(nullptr),
 #endif  // WITH_PYTHON
 	m_samples(samples),
 	m_stereoMode(stereoMode),
@@ -276,7 +275,7 @@ void LA_Launcher::InitEngine()
 #ifdef WITH_PYTHON
 	KX_SetMainPath(std::string(m_maggie->name));
 	// Some python things.
-	setupGamePython(m_ketsjiEngine, m_maggie, m_globalDict, &m_gameLogic, m_argc, m_argv);
+	setupGamePython(m_ketsjiEngine, m_maggie, m_globalDict, m_argc, m_argv);
 #endif  // WITH_PYTHON
 
 	// Create a scene converter, create and convert the stratingscene.
@@ -325,19 +324,6 @@ void LA_Launcher::ExitEngine()
 	DEV_Joystick::Close();
 	m_ketsjiEngine->StopEngine();
 
-#ifdef WITH_PYTHON
-
-	/* Clears the dictionary by hand:
-	 * This prevents, extra references to global variables
-	 * inside the GameLogic dictionary when the python interpreter is finalized.
-	 * which allows the scene to safely delete them :)
-	 * see: (space.c)->start_game
-	 */
-
-	PyDict_Clear(PyModule_GetDict(m_gameLogic));
-
-#endif  // WITH_PYTHON
-
 	// Do we will stop ?
 	if ((m_exitRequested != KX_ExitRequest::RESTART_GAME) && (m_exitRequested != KX_ExitRequest::START_OTHER_GAME)) {
 		// Then set the cursor back to normal here to avoid set the cursor visible between two game load.

source/gameengine/Launcher/LA_Launcher.h

@@ -82,7 +82,6 @@ class LA_Launcher
 
 #ifdef WITH_PYTHON
 	PyObject *m_globalDict;
-	PyObject *m_gameLogic;
 #endif  // WITH_PYTHON
 
 	/// The number of render samples.

source/gameengine/VideoTexture/blendVideoTex.cpp

@@ -214,6 +214,7 @@ PyMODINIT_FUNC initVideoTexturePythonBinding(void)
 	pyImageTypes.reg(m);
 	pyFilterTypes.reg(m);
 
+	Py_INCREF(&Texture::Type);
 	PyModule_AddObject(m, "Texture", (PyObject *)&Texture::Type);
 #ifdef WITH_GAMEENGINE_DECKLINK
 	Py_INCREF(&DeckLinkType);