Graph Nodes
Spawn Query graph is essentially a decision tree. Each node has an active state, and inactive nodes will be neglected from the decision tree.
Samplers
Sampler nodes are the final nodes that yield results.
You can create your own sampler nodes in Blueprints. See Blueprintable Types.
Pool
Randomly select a row from a table.
Randomization Policy: determines how a row is picked. See Randomization Policy.
Branch Weight: how to calculate the branch weight based on the pool table. The branch weight is used by the composite node parent for selecting a branch.
Query
Use another Spawn Query graph to select an entry. The node is not active when the graph is not active.
Note: recursion is not allowed.
Composites
A composites node have one or more children. It delegates the query to one of its children.
Priority Selector
Always select the leftmost active branch, by default.
Reverse Direction: if checked, select the rightmost.
Dynamic: if checked, lower the priority of the branch after it yields a result.
Random Selector
Select an active branch randomly.
Randomization Policy: determines how a branch is picked. See Randomization Policy.
Decorators
Decorators are nodes that attached to the branch's main node. It may render the branch inactive, rewrite the output, or change the branch's weight, etc.
You can create your own decorator nodes in Blueprints. See Blueprintable Types.
Weight Override
Change the branch's weight to a constant or a blackboard value.
Condition
Compare blackboard values and deactivate the branch when the condition is not met.