BGE Python API

Free python modules defined within the blendfile between loading scenes since they would end up accessing old GameLogic, Rasterizer modules as well as old game engine data in the module namespace which can cause problems.

source/blender/python/api2_2x/bpy_internal_import.c

@@ -265,3 +265,65 @@ static PyObject *blender_reload( PyObject * self, PyObject * args )
 PyMethodDef bpy_import[] = { {"bpy_import", blender_import, METH_KEYWORDS, "blenders import"} };
 PyMethodDef bpy_reload[] = { {"bpy_reload", blender_reload, METH_VARARGS, "blenders reload"} };
 
+
+/* Clear user modules.
+ * This is to clear any modules that could be defined from running scripts in blender.
+ * 
+ * Its also needed for the BGE Python api so imported scripts are not used between levels
+ * 
+ * This clears every modules that has a __file__ attribute (is not a builtin)
+ * and is a filename only (no path). since pythons bultins include a full path even for win32.
+ * even if we remove a python module a reimport will bring it back again.
+ */
+
+
+#if defined(WIN32) || defined(WIN64)
+#define SEPSTR "\\"
+#else
+#define SEPSTR "/"
+#endif
+
+
+void importClearUserModules(void)
+{
+	PyObject *modules= PySys_GetObject("modules");	
+	
+	char *fname;
+	char *file_extension;
+	
+	/* looping over the dict */
+	PyObject *key, *value;
+	Py_ssize_t pos = 0;
+	
+	/* new list */
+	PyObject *list= PyList_New(0);
+	
+	/* go over sys.modules and remove anything with a 
+	 * sys.modukes[x].__file__ thats ends with a .py and has no path
+	 */
+	while (PyDict_Next(modules, &pos, &key, &value)) {
+		fname= PyModule_GetFilename(value);
+		if(fname) {
+			if ((strstr(fname, SEPSTR))==0) { /* no path ? */
+				file_extension = strstr(fname, ".py");
+				if(file_extension && *(file_extension + 3) == '\0') { /* .py extension ? */
+					/* now we can be fairly sure its a python import from the blendfile */
+					PyList_Append(list, key); /* free'd with the list */
+				}
+			}
+		}
+		else {
+			PyErr_Clear();
+		}
+	}
+	
+	/* remove all our modules */
+	for(pos=0; pos < PyList_Size(list); pos++) {
+		/* PyObject_Print(key, stderr, 0); */
+		key= PyList_GET_ITEM(list, pos);
+		PyDict_DelItem(modules, key);
+	}
+	
+	Py_DECREF(list); /* removes all references from append */
+}
+

source/blender/python/api2_2x/bpy_internal_import.h

@@ -37,6 +37,7 @@
 
 PyObject *importText( char *name, int *found );
 PyObject *reimportText( PyObject *module, int *found );
+void importClearUserModules( void ); /* Clear user modules */
 extern PyMethodDef bpy_import[];
 extern PyMethodDef bpy_reload[];
 

source/gameengine/Ketsji/KX_PythonInit.cpp

@@ -102,7 +102,7 @@ extern "C" {
 #include "GPU_material.h"
 
 static void setSandbox(TPythonSecurityLevel level);
-
+static void clearGameModules();
 
 // 'local' copy of canvas ptr, for window height/width python scripts
 static RAS_ICanvas* gp_Canvas = NULL;
@@ -1402,6 +1402,10 @@ PyObject* initGamePythonScripting(const STR_String& progname, TPythonSecurityLev
 	initPyTypes();
 	
 	bpy_import_main_set(maggie);
+	
+	/* run this to clear game modules and user modules which
+	 * may contain references to in game data */
+	clearGameModules();
 
 	PyObject* moduleobj = PyImport_AddModule("__main__");
 	return PyModule_GetDict(moduleobj);
@@ -1434,6 +1438,9 @@ static void clearGameModules()
 	clearModule(modules, "Mathutils");	
 	clearModule(modules, "BGL");	
 	PyErr_Clear(); // incase some of these were alredy removed.
+	
+	/* clear user defined modules */
+	importClearUserModules();
 }
 
 void exitGamePythonScripting()