Ports

class NodePort

What?

Ports are the gates to communication between nodes. They can be either an input or an output, has a reference to its parent node, and contains methods to return connected ports. They have a type variable, which defines the color of the node, and potentially which other nodes it can connect to. Some ports are dynamic.

How?

Ports can be added by adding either an [Input] or an [Output] attribute to serialized variable. General rule of thumb is; if Unity can serialize it, it can be a port.

You might want to dynamically add and remove ports. Read more about dynamic ports.

Typical usage of ports include (in a node class):

// Get the connected node.
NodePort otherPort = GetOutputPort("myOutput").Connection
if (otherPort != null) {
  MyNode nextNode = otherPort.node as MyNode;
}

// Get the sum of all number inputs added together
return GetInputPort("myInput").GetInputSum(myInput);

Parameters

Port attributes also support a number of parameters:

• backingValue - When to show the backing field value.
• connectionType - How many connections to allow for this port
• dynamicPortList - If true, will display a port per list item instead of one port for the entire list
• typeConstraint - Limit which value types you can connect to this port