BTGraphEditor

A Godot 4.2 addon for editing, debugging, and running behavior tree graphs. GDExtension binaries for Windows, Linux, and MacOS(Unsigned).

Features

These are the main features of the addon.

• Edit Behavior Trees using a graph editor.
• Optional window for debugging BTGraphs in realtime.
• Custom C++ node for speeding up the interpretation of BTGraphs.

Components

These are the components of the addon.

• BTInterpreter: Interprets BTGraphs.
  • connect_to_signal(sig_name : String, to_this : Callable): Best way to connect an external callable to a signal in the signal Array.
  • edit_variable(var_name, value): Best way to set a variable in the variable Array.
  • set_random_seed(seed): Best way to set the "random_seed" variable.
  • skip_all_current_nodes(): Skip all nodes that are waiting.
  • skip_current_node(which_branch : int): Skip the current node on a branch that is waiting.
  • stop_a_branch(which_branch : int): Stop the current branch.
  • stop_all_branches(): Stop all branches / reset behavior tree.
• BTInterpreterCPP: C++ component for interpreting BTGraphs. Must be a sibling of a [BTInterpreter].
• BTSimulationGraph: The window for viewing a simulation of the BTGraph of a [BTInterpreter] in runtime. Display > Window > Sub windows > Embed Sub windows to show this in a separate window.
  • get_all_interpreters(var_name, value): Best way to set a variable in the variable Array.
  • add_one_interpreter(var_name, value): Best way to set a variable in the variable Array.

# Example of using some of the functions
func example():
	bt_interpreter = get_node("BTInterpreter")
	(bt_interpreter as BTInterpreter).connect_to_signal("SignalTest", self.callable_test)
	(bt_interpreter as BTInterpreter).edit_variable("BoolTest", true)
	(bt_interpreter as BTInterpreter).set_random_seed((position.x + 1) * (position.y + 1))

Graph Nodes

These are the nodes used in a graph.

• BoolNode: Will do an AND, OR, XOR, or NOT operations on inputs.
• StatementNode: Will do <, >, or = operations on inputs.
• VariableNode: Input variables for the graph. Can be booleans, integers, or floats.
• IfNode: Takes a boolean input and outputs based on that value.
• SequencerNode: Chooses between multiple outputs based on the type of sequencer: Top-Down, Parallel, Random, and Totally Random.
• SignalNode: Emits a signal.
• ActionNode: Calls a function as a callable. Can wait on a true return, false return, or nothing.
• WaitNode: Waits for an amount time or on a signal to be emitted.
• CommentNode: A comment box in a BTGraph. (This Node can be buggy when moved / dragged behind other nodes)

# Example of a function that can be called by an Action Node. Action Node waits for bt_wait[0] to be true.
func BTAction_example (bt_wait : Array):
	if bt_wait:
		if position.distance_to(target.position) < 1:
			velocity = Vector3.ZERO
            		print("Got To Target!")
			bt_wait[0] = true
		else:
            		print("Going To Target...")
			bt_wait[0] = false

Installation

You can download the whole demo project and open it with Godot or download the "/btgrapheditor" folder from the "/addon" folder and put it in your "/addon" folder in your project. Make sure to enable the addon in your Project Settings.