Find the right node
The four jobs a node can do, with every control in the product listed under the one it belongs to, and the exact rule one click away.
On this page
Start with what you want the graph to do. Every node belongs to one of four jobs, and every entry carries its fields, its result rule, and the guide that shows it working on a real game.
Four families of node
Every graph is built from these four jobs. Each node opens its reference entry.
Choose and order
Pick between alternatives or work through steps.
Change one child
Wrap a branch to repeat it, time it, or gate it.
Do and check
Reach into your C# to act on the game or read a fact.
Where it runs
Hold a mode, leave it on a condition, and host a tree inside it.
The three reference pages
Section titled “The three reference pages”- Behavior tree nodes: the composites, the decorators, and the leaves that act or check.
- Member nodes and bindings: the six node kinds that reach into your C#, with the binding controls they share.
- State machine controls: states, transitions, lifecycle actions, and a hosted tree.
Teaching pages, with the problem each node solves, are at behavior trees, state machines, and bindings. A control you remember from another asset and cannot find here is probably on what it does not do yet.
Behavior Tree controls
Section titled “Behavior Tree controls”Organize a plan
Section titled “Organize a plan”- Selector: try alternatives in priority order, such as attacking before patrolling. Guide: choose.
- Random Selector: choose between weighted alternatives, such as different enemy waves. Guide: roll the dice.
- Sequence: perform steps in order, such as checking a target before attacking. Guide: in order.
- Parallel: group the children that all have to succeed. This release visits them one at a time, in Children order. Guide: do together.
- Subgraph: reuse a Behavior Tree as part of a larger plan. Guide: reuse a branch.
Change how work runs
Section titled “Change how work runs”- Repeat: run a child repeatedly, such as continuing a patrol. Guide: keep going.
- Time Limit: give a child a limited amount of time to finish. Guide: give up after.
- Inverter: turn a child’s Success into Failure, or Failure into Success. Guide: flip it.
- Conditional: allow a child to run only when its condition permits it. Guide: only if.
Check or do something
Section titled “Check or do something”- Condition: check a blackboard fact before continuing. Guide: actions and conditions.
- Action: request an operation from your game’s action or service implementation. Guide: actions and conditions.
- Move To: request movement to a position through your movement adapter. Guide: move somewhere.
Member nodes
Section titled “Member nodes”These nodes connect a graph to the C# your game already has.
- Method: call a method, supply its arguments, and use its result. Guide: method.
- Property: read, write, or synchronize a property. Guide: property and field.
- Field: read, write, or synchronize a field. Guide: property and field.
- Message: send a fire-and-forget call to a void method. Guide: message.
- Member Condition: check a method, property, or field against an expected value. Guide: condition and event.
- Event Condition: wait for an event before continuing. Guide: condition and event.
State Machine controls
Section titled “State Machine controls”- Root: organize the machine’s top-level states. Guide: state machines.
- State: define a mode and the work it owns. Guide: states and lifecycle.
- Entry State: choose where the machine starts. Guide: states and lifecycle.
- Transition: decide when to leave one state and enter another. Guide: transitions.
- Any State: define a transition rule that applies across the machine. Guide: any state.
- Referenced State Machine: run a reusable machine inside a state. Guide: referenced machines.
A state can also carry lifecycle actions or a hosted Behavior Tree.
Looking for a C# type
Section titled “Looking for a C# type”Signatures, parameters, and the public surface of the runtime and editor assemblies are in the generated API reference.