Update

2023/scripts/rigging_tools/ngskintools2/observableValue.py

@@ -0,0 +1,25 @@
+from ngSkinTools2.api.python_compatibility import Object
+from ngSkinTools2.signal import Signal
+
+
+class Undefined(Object):
+    pass
+
+
+class ObservableValue(Object):
+    def __init__(self, default_value=Undefined):
+        self.value = default_value
+        self.changed = Signal("observable value")
+
+    def set(self, value):
+        self.value = value
+        self.changed.emit()
+
+    def __call__(self, default=Undefined, *args, **kwargs):
+        if self.value != Undefined:
+            return self.value
+
+        if default != Undefined:
+            return default
+
+        raise Exception("using observable value before setting it")