Implement a node
Nodes are the fundamental building blocks of any graph. This page shows how to create custom node types with input and output ports.
It covers the node visual implementation but not the execution logic, as the later depends on your graph tool's purpose.
Create a new type of node
To create a node, define a class that inherits from the Node base class. To ensure automatic discovery, define your node class in the same assembly as your graph tool. The node class name serves as the node's title in the interface.
[Serializable]
public class BasicNode : Node
{
}
Note
Notice that the nodes include a Serializable attribute. This attribute enables the tool to write your nodes into the graph asset and deserialize them when you open the graph.
Define ports
Configure the data connections for your node by overriding the OnDefinePorts method and using the AddInputPort
and AddOutputPort methods of the IPortDefinitionContext interface.
protected override void OnDefinePorts(IPortDefinitionContext context)
{
context.AddInputPort("Input").Build();
context.AddInputPort<int>("a").Build();
context.AddOutputPort("Output").Build();
context.AddOutputPort<int>("result").Build();
}
Note
Ports support any Unity-compatible type, including your custom types. Omitting a type creates connection-only ports that link nodes without transferring data.
Tip
Use optional methods such as WithDisplayName or WithConnectorUI to customize your port.
context.AddInputPort<int>("a")
.WithDisplayName("My Int")
.WithConnectorUI(PortConnectorUI.Arrowhead)
.Build();
Node complete example
[Serializable]
public class BasicNodeFinal : Node
{
protected override void OnDefinePorts(IPortDefinitionContext context)
{
context.AddInputPort("Input").Build();
context.AddInputPort<int>("a").Build();
context.AddOutputPort("Output").Build();
context.AddOutputPort<int>("result").Build();
}
}