import type { GraphEdge, GraphLayout, GraphNode, GraphNodeState } from './graph.types';
export interface ForceSettings {
    /** Node-node repulsion. Larger spreads the graph out. @default 900 */
    repulsion?: number;
    /** Edge spring stiffness, 0-1. @default 0.08 */
    springStrength?: number;
    /** Preferred edge length at rest. @default 70 */
    springLength?: number;
    /** Pull toward the origin, which stops islands drifting away. @default 0.015 */
    centering?: number;
    /** Velocity retained per tick. @default 0.82 */
    damping?: number;
    /** Barnes-Hut accuracy; see `octree.ts`. @default 0.8 */
    theta?: number;
    /** Below this total movement the layout is considered settled. @default 0.05 */
    settleThreshold?: number;
    /**
     * Floor on the separation used for repulsion, in layout units.
     * @default 6
     */
    minDistance?: number;
    /**
     * Hard cap on how far a node may move in one tick.
     *
     * A speed limit is what keeps a bad initial configuration from throwing nodes
     * off to infinity before damping has any chance to bite.
     * @default 30
     */
    maxVelocity?: number;
    /**
     * Fraction of the remaining energy shed each tick.
     *
     * This is what *guarantees* termination: forces are scaled by a cooling alpha,
     * so the layout always converges instead of orbiting forever and pinning a CPU
     * core on a dashboard nobody is looking at.
     * @default 0.022
     */
    alphaDecay?: number;
    /** Alpha below which the layout is done. @default 0.002 */
    alphaMin?: number;
}
/** Places nodes on a sphere (or circle in 2D) before the forces take over. */
export declare function seedPositions(nodes: GraphNode[], layout: GraphLayout): GraphNodeState[];
export interface TickResult {
    /** Average distance a node moved this tick. */
    movement: number;
    settled: boolean;
    /** Remaining energy, to be fed into the next tick. */
    alpha: number;
}
/**
 * Advances the layout by one step.
 *
 * @description
 * Three forces: Barnes-Hut repulsion between all nodes, Hooke springs along the
 * edges, and a weak pull toward the origin so disconnected components do not
 * drift off screen forever.
 *
 * `states` is mutated in place — a tick allocates only the octree, which matters
 * when this runs sixty times a second over thousands of nodes.
 */
export declare function tick(states: GraphNodeState[], edges: GraphEdge[], indexById: Map<string, number>, layout: GraphLayout, settings?: ForceSettings, 
/** Remaining energy, from the previous tick. */
alpha?: number): TickResult;
/**
 * Runs the layout to rest without animating.
 *
 * Used when the viewer asked for reduced motion, and when producing a static
 * image: the diagram appears already arranged rather than visibly settling.
 */
export declare function runToSettle(states: GraphNodeState[], edges: GraphEdge[], indexById: Map<string, number>, layout: GraphLayout, settings?: ForceSettings, maxIterations?: number): number;