To register a graph type and associate it with a custom file extension and configuration options, apply the GraphAttribute to your custom Graph class.

You can further control the graph's behavior using the GraphOptions enum, which defines traits such as support for subgraphs. If your graph supports subgraphs (via SupportsSubgraphs), you can declare valid subgraph types using the SubgraphAttribute.

Use the GraphDatabase utility class to create, load, and save graph assets in the Unity Editor. Graphs are serialized assets. You can create them through the editor UI with PromptInProjectBrowserToCreateNewAsset<T>(string) or load them from disk with LoadGraph<T>(string).

Properties

name

The name of the graph.

Declaration

public string name { get; }

Property Value

Type	Description
string

nodeCount

The number of INodes in the graph.

Declaration

public int nodeCount { get; }

Property Value

Type	Description
int

variableCount

The number of IVariables declared in the graph.

Declaration

public int variableCount { get; }

Property Value

Type	Description
int

Methods

GetNode(int)

Retrieves a node defined in the graph by its index.

Declaration

public INode GetNode(int index)

Parameters

Type	Name	Description
int	index	The zero-based index of the node to retrieve.

Returns

Type	Description
INode	The INode at the specified index.

Remarks

Use this method to access a node based on its creation order in the graph. The index is zero-based and must be within range (see: nodeCount).
The list includes:

It excludes BlockNodes, which are only accessible through their parent ContextNode.

GetNodes()

Retrieves all nodes in the graph.

Declaration

public IEnumerable<INode> GetNodes()

Returns

Type	Description
IEnumerable<INode>	An `IEnumerable` of all INodes in the graph.

Remarks

Use this method to access every node in the graph. Nodes are returned in the order they were created.
The list includes:

It excludes BlockNodes, which are only accessible through their parent ContextNode.

GetVariable(int)

Retrieves a variable declared in the graph by index.

Declaration

public IVariable GetVariable(int index)

Parameters

Type	Name	Description
int	index	The index of the variable to retrieve.

Returns

Type	Description
IVariable	The IVariable at the specified index.

Remarks

Use this method to access a specific IVariable from the list of variables declared in the graph. This list does not include variable nodes that reference variables. The index is zero-based and reflects the order in which the variables were created. The index must be within the valid range of the variable list (see: variableCount).

GetVariables()

Retrieves all variables declared in the graph.

Declaration

public IEnumerable<IVariable> GetVariables()

Returns

Type	Description
IEnumerable<IVariable>	An `IEnumerable` of all IVariables declared in the graph.

Remarks

Use this method to enumerate all IVariables declared in the graph. This list does not include variable nodes that reference variables. The collection reflects the variables as declared, in their order of creation.

OnDisable()

Called when the graph is unloaded, or goes out of scope in the editor.

Declaration

public virtual void OnDisable()

Remarks

Unity calls this method when the graph is disabled, or is destroyed. Override this method to release resources, clear temporary data, or perform any required cleanup. This method complements OnEnable() and is useful for maintaining consistency across editor sessions.

OnEnable()

Called when the graph is created or loaded in the editor.

Declaration

public virtual void OnEnable()

Remarks

Override this method to perform setup tasks, such as allocating resources, initializing internal state, or preparing data for editing. This method is invoked each time the graph becomes active in the editor, including after domain reload or when reopening the asset. This method complements OnDisable() and is useful for maintaining consistency across editor sessions.

OnGraphChanged(GraphLogger)

Called after the graph has changed.

Declaration

public virtual void OnGraphChanged(GraphLogger graphLogger)

Parameters

Type	Name	Description
GraphLogger	graphLogger	The GraphLogger that receives any errors or warnings related to the graph.

Remarks

Unity calls this method after any change to the graph. Override it to validate the graph's integrity and report issues using the provided GraphLogger. Use this method to detect invalid configurations, highlight issues in the editor, or provide user feedback. Do not modify the graph within this method, as it may cause instability or recursive updates.