I’m trying to write an Omnigraph node implementation that subscribes to a custom ROS message. I want the node state to reset to its initial state when the model is stopped. I have a few questions:
Isaac Sim guide describes one function (compute), which is called (probably) when a signal arrives at the execution input. What are other functions exist?
What node functions are called when opening/closing the graph, starting the model, stopping the model? I would like to get a description like this:
Simulink Engine Interaction with C S-Functions - MATLAB & Simulink
I have met the release and initialize functions in the code of other OmnyGraph nodes. What are their functional purposes? When are they called?
this tutorial lists all of the ABIs that can be overridden
In isaac sim we use this base class for nodes that need to reset when simulation is stopped.
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Base class for nodes that automatically reset when stop is pressed.
def __init__(self, initialize=False):
self.initialized = initialize
stage = omni.usd.get_context()
self.stage_event_sub = stage.get_stage_event_stream().create_subscription_to_pop(
def on_stage_event(self, event: carb.events.IEvent):
if event.type == int(omni.usd.StageEventType.SIMULATION_STOP_PLAY):
self.initialized = False
# Defined by subclass
self.stage_event_sub = None
self.initialized = None
Hammad_M, thank you so much for your helpness.
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