import type { EntityStore } from "../scene/entityStore.js";
/** A render pose sampled between two simulation steps: `[x, y, z, rotationY]`. */
export type RenderPose = [x: number, y: number, z: number, rotationY: number];
/** Serializable previous-step poses keyed by entity id. */
export interface PoseHistoryState {
    previous: Record<string, RenderPose>;
}
/** Previous-step pose buffer: capture at each fixed step, sample between steps for rendering. */
export interface PoseHistory {
    /** Capture every entity's current pose as the "previous" step. Call once at the start of each fixed step. */
    beginStep(entities: EntityStore): void;
    /**
     * Write the pose `alpha` of the way from the previous step to the live pose into `out`. Returns `false` (and
     * leaves `out` untouched) when the entity is unknown; an entity with no history or one that jumped farther
     * than `snapDistance` gets its live pose.
     */
    sample(entities: EntityStore, id: string, alpha: number, out: RenderPose): boolean;
    /** Forget an entity's previous pose so its next frame renders live (respawn, teleport). */
    snap(id: string): void;
    retune(options: {
        snapDistance?: number;
    }): void;
    snapshot(): PoseHistoryState;
    restore(state: PoseHistoryState): void;
}
/** Shortest-arc interpolation between two yaw angles. */
export declare function lerpAngle(from: number, to: number, t: number): number;
/**
 * Previous-step pose buffer for render interpolation under a fixed-step loop. Reuses one 4-slot array per
 * entity so a step over N entities allocates only for entities seen for the first time.
 *
 * @capability pose-interpolation render entity poses between fixed simulation steps without stutter
 */
export declare function createPoseHistory(options?: {
    snapDistance?: number;
}): PoseHistory;