# Render Converter Converter Source
# a bidirectional connection
-class Element:
+class Element(object):
CHANGED_DEFAULT = 0 # initial "pull" state
CHANGED_ALL = 1 # really everything changed
CHANGED_CLEAR = 2 # we're expecting a real update soon. don't bother polling NOW, but clear data.
self.downstream_elements = CList()
self.master = None
self.source = None
+ self.__suspended = True
self.clearCache()
def connectDownstream(self, downstream):
def clearCache(self):
self.cache = None
+
+ def setSuspend(self, suspended):
+ changed = self.__suspended != suspended
+ if not self.__suspended and suspended:
+ self.doSuspend(1)
+ elif self.__suspended and not suspended:
+ self.doSuspend(0)
+
+ self.__suspended = suspended
+ if self.source is not None and changed:
+ self.source.checkSuspend()
+
+ suspended = property(lambda self: self.__suspended, setSuspend)
+
+ def checkSuspend(self):
+ self.suspended = reduce(lambda x, y: x and y.__suspended, self.downstream_elements, True)
+
+ def doSuspend(self, suspend):
+ pass