5.3. How data is stored within a node

Data stays in a node input port until it is replaced by other data. If you detach a cable while the composition is running, the input port will keep the latest data that came through that cable.

Some nodes have state. A stateful node retains information from the last time it executed. An example of a stateful node is Count. If a Count node is told to increment, its state (the retained count) changes.

Stateful nodes have a thick bar along the bottom that resembles a data-and-event cable. This symbolizes that the node’s state data is kept after the node executes, and used next time it executes.

A stateless node doesn’t retain any information about previous times it executed. If you give it the same inputs, it’ll always give you the same outputs. Stateless nodes have a thin bottom border.