Latent function nodes are collectively called all nodes that take some time to complete. The most prominent of such nodes would be the Wait node, while another one would be the Tween Position (yes, FlowCanvas includes a set of native tweening nodes!). All such nodes have some common flow inputs and outputs.

Let’s begin with the flow outputs first:

Start, will be called once as soon as the node is called.
Update, will continuously be called for as long as the node is doing whatever it is that it does.
Finish, will be called once after the node has finished execution.

Respectively for the inputs:

In, is the regular call flow input.
Break, will stop the node from executing and the Finish output will be called.
Cancel, will stop the node from executing and the Finish output will NOT be called.

Invocation Mode

All latent nodes also have an option in their inspector called ‘invocation mode’, that tells the node how to handle input calls if the node is still running. The possible options are as follows:

Filter Calls, will simply ignore any calls made while the node is still running.
Queue Calls, will queue the calls and as such, when the node is finished its current execution, the next call in the queue will take place.

Following is an example of the Wait node set to queue calls. In this example, Wait is called multiple times at the beginning of the example. The amount of calls in the queue can also be seen in the node title in square brackets.