/** One topic in the hierarchy. Owns the shared `LyraTopic` shape for the whole component, the same
*  way `word-cloud-layout.ts` owns `WordCloudWord`. */
export interface LyraTopic{id:string;label:string;children?:readonly LyraTopic[];}
/** A topic after radial layout — original id/label plus computed geometry. */
export interface PlacedTopic{id:string;label:string;depth:number;x:number;y:number;
/** Radians, measured clockwise from 12 o'clock (0) in LTR -- used both to draw a parent-child
*  connector's control point and, in tests, to verify arc subdivision independent of the
*  bounding-box-shifted x/y. */
angle:number;parentId:string|null;hasChildren:boolean;
/** Always `false` for a leaf (`hasChildren: false`). */
expanded:boolean;}export interface MindMapLayoutOptions{
/** Radius step per depth ring, in px. */
ringGap:number;rtl:boolean;isExpanded:(id:string,depth:number)=>boolean;}export interface MindMapLayoutResult{placed:PlacedTopic[];links:{fromId:string;toId:string;}[];
/** viewBox width/height, auto-fit to the laid-out extent with padding. */
width:number;height:number;
/** The root/hub's position within the shifted (viewBox-relative) coordinate space. */
centerX:number;centerY:number;}
/**
* Lays out `topics` as a radial tree: root at the center, each depth ring at radius `depth *
* ringGap`, each parent's children dividing its own inherited angular arc proportionally to their
* visible leaf counts (a collapsed subtree counts as one leaf), sibling order running clockwise
* from 12 o'clock in LTR (counter-clockwise in RTL, via `rtl`). Multiple roots hang off an
* implicit `'__hub__'`-id center node labeled `hubLabel`. Pure function, no DOM access -- see
* `<lr-mind-map>` for the component wrapping this.
*/
export declare function layoutMindMap(topics:readonly LyraTopic[],hubLabel:string,opts:MindMapLayoutOptions):MindMapLayoutResult;