simplify calls needed to initialize items

pyqtgraph/opengl/GLGraphicsItem.py

@@ -228,10 +228,11 @@ class GLGraphicsItem(QtCore.QObject):
         view, as it may be obscured or outside of the current view area."""
         return self.__visible
     
-    def setInitialized(self, init=True):
-        self.__initialized = init
+    def initialize(self):
+        self.initializeGL()
+        self.__initialized = True
 
-    def initialized(self):
+    def isInitialized(self):
         return self.__initialized
     
     def initializeGL(self):
@@ -240,7 +241,7 @@ class GLGraphicsItem(QtCore.QObject):
         The widget's GL context is made current before this method is called.
         (So this would be an appropriate time to generate lists, upload textures, etc.)
         """
-        self.setInitialized()
+        pass
     
     def setupGLState(self):
         """

pyqtgraph/opengl/GLViewWidget.py

@@ -102,8 +102,7 @@ class GLViewWidget(QtWidgets.QOpenGLWidget):
         if self.isValid():
             self.makeCurrent()
             try:
-                item.initializeGL()
-                item.setInitialized()
+                item.initialize()
             except:
                 self.checkOpenGLVersion('Error while adding item %s to GLViewWidget.' % str(item))
                 
@@ -129,10 +128,12 @@ class GLViewWidget(QtWidgets.QOpenGLWidget):
         self.update()        
         
     def initializeGL(self):
+        """
+        Initialize items that were not initialized during addItem().
+        """
         for item in self.items:
-            if not item.initialized():
-                item.initializeGL()
-                item.setInitialized()
+            if not item.isInitialized():
+                item.initialize()
         
     def setBackgroundColor(self, *args, **kwds):
         """