Animation Node Reference
Animation Blueprints make use of various nodes within their graphs to perform operations on input poses, such as blending, direct bone manipulation, and more. There are a few distinct types of animation nodes provided in the engine including events, blend nodes, skeletal controllers, space nodes, and conversion nodes.
Pins and Properties
Animation nodes can have pins (both input and output) which values can be passed to in the EventGraph or AnimGraph and properties which can be edited in the Details panel. Pins can be either data pins identical to those found on nodes in regular Blueprints which take in data from variables or pure functions, or they can be pose pins which are similar to exec pins in regular Blueprints in that they determine the flow of execution.
Data pins are actually properties like any other and are exposed in the Details panel. These can be toggled between being used as a data pin on the node in the graph and being a simple property. When exposed as a data pin, the property is only modifiable in the graph by linking a value to it. When not exposed as a data pin, properties can only be modified through the Details panel.