Package dev.twilite.game.simulation.rollout

Class RolloutSearch<S,A>

java.lang.Object

dev.twilite.game.simulation.rollout.RolloutSearch<S,A>

Type Parameters:

S - simulated state type

A - action type

public class RolloutSearch<S,A>
extends Object

Generic branch-local rollout search for mutable game-state problems.

Unlike Simulation, this search does not merge candidates by coordinate. Each branch carries its own state, which makes it suitable for combat prediction where NPC positions, attack cooldowns, or projectiles differ depending on the exact actions taken earlier in the branch.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final record	RolloutSearch.ActionsBuilder<S,A>	Builder step after legal actions are known.
static final record	RolloutSearch.Builder<S,A>	Builder for a rollout search.
static final record	RolloutSearch.EvaluateBuilder<S,A>	Final builder step for optional terminal configuration and construction.
static final record	RolloutSearch.TransitionBuilder<S,A>	Builder step after actions and transition are known.

Constructor Summary

Constructors

Constructor	Description
RolloutSearch(RolloutOptions options, Function<S,? extends Collection<A>> actions, BiFunction<S,A,S> transition, ToIntFunction<RolloutNode<S,A>> evaluator, Predicate<RolloutNode<S,A>> terminal)	Creates a rollout search.

Method Summary

Modifier and Type	Method	Description
static <S, A> RolloutSearch.Builder<S,A>	create(RolloutOptions options)	Starts a rollout search builder.
Optional<RolloutResult<S,A>>	run(S initial)	Runs the search from an initial state.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

RolloutSearch

public RolloutSearch(RolloutOptions options,
 Function<S,? extends Collection<A>> actions,
 BiFunction<S,A,S> transition,
 ToIntFunction<RolloutNode<S,A>> evaluator,
 Predicate<RolloutNode<S,A>> terminal)

Creates a rollout search.

Parameters:

options - search limits

actions - supplies legal actions for a state

transition - applies an action and returns the next branch state

evaluator - scores a branch node

terminal - returns whether a branch should stop expanding

Method Details

create

public static <S,
A> RolloutSearch.Builder<S,A> create(RolloutOptions options)

Starts a rollout search builder.

Type Parameters:

S - simulated state type

A - action type

Parameters:

options - search limits

run

public Optional<RolloutResult<S,A>> run(S initial)

Runs the search from an initial state.

Parameters:

initial - initial simulated state

Returns:

selected branch, or empty when the root has no actions