import { PointOnShape } from '../point-on-shape/point-on-shape.js';
/**
 * The primary interface of the library.
 *
 * Since the MAT is a full representation of the shape boundary an instance of
 * this class contains both the information of a boundary point and a medial
 * axis point (and edge to the next point(s)). It also contains edges to other
 * `CpNode`s which allows for traversal of the MAT and thus implictly
 * represents the entire MAT.
 *
 * To get the maximal disk circle (of which the center is on the medial axis)
 * use `cp.circle`.
 *
 * To get the boundary point, use `cp.pointOnShape`.
 *
 * The edge `next` (resp. `prev`) allows one to move anti-clockwise (resp.
 * clockwise) on the shape boundary to the next `CpNode`. This also imposes a
 * direction of traversal of the MAT edges and vertices.
 *
 * The edge `nextOnCircle` (resp. `prevOnCircle`) allows one to go
 * anti-clockwise (resp. clockwise) around the maximal disks implied by
 * the CpNode to the next maximal disk contact point. This is equivalent to
 * following other branches on the MAT.
 *
 * Call `getMatCurveBetween(cpNodeFrom, cpNodeTo)` or `getMatCurveToNext(cpNode)`
 * (replacing the older CpNode.`matCurveToNextVertex`) to get a bezier curve
 * from the maximal disk of this `CpNode` to the next `CpNode`'s
 * maximal disk and thus directly representing a piece of the medial axis.
 *
 * The function, `getChildren`, returns the children of this `CpNode` when
 * seen as a MAT edge. Only children in a 'forward' direction are returned. These
 * include all edges except the 'backward' edge given by `prevOnCircle`. For
 * `CpNode`s having a maximal disk with 2 contact points (a 2-prong, the usual
 * case) the children will be the single edge `next`. For a 3-prong this will
 * be the edges `next` and `nextOnCircle`, etc. `getChildren` allows one to
 * easily traverse the MAT tree - see e.g. the implementation of `traverseEdges`.
 *
 * The getter, `getVertexForwardChildren`, is similar to `getChildren` but returns the
 * child nodes of the tree when `CpNode` is seen as a MAT vertex point (as
 * opposed to edge). In this way the dual graph of the tree can easily be
 * traversed - see e.g. `traverseVertices`. Generally, however, traversing the
 * edges is preferred as it returns the entire Medial Axis (by utilizing
 * `getMatCurveToNext` on each returned edge).
 *
 * It may be worth mentioning that by traversing from the CpNode by following
 * `next` repeatedly until one is back at the same CpNode allows one
 * to 'go around' the shape boundary and at the same time traverse the MAT twice
 * in opposite directions.
 */
interface CpNode {
    /** For debugging / easy identification only */
    readonly id: number;
    /** The shape boundary contact point, i.e. a `CpNode` without its edges. */
    readonly pointOnShape: PointOnShape;
    /** If true, this `CpNode` belongs to a hole-closing maximal disk. */
    readonly isHoleClosing: boolean;
    /** true if this `CpNode` is at a shape boundary intersection point, false otherwise */
    readonly isIntersection: boolean;
    /** The previous (going clockwise around the boundary) contact point `CpNode`. */
    readonly prev: CpNode;
    /** The next (going anti-clockwise around the boundary) contact point `CpNode`. */
    readonly next: CpNode;
    /**
     * The previous `CpNode` (going clockwise around the inscribed circle
     * defined by the maximal disk).
     */
    readonly prevOnCircle: CpNode;
    /**
     * The next `CpNode` (going anti-clockwise around
     * the inscribed circle defined by the maximal disk).
     */
    readonly nextOnCircle: CpNode;
    /**
     * For hole closers only - the twin `CpNode` at the same point, e.g.
     * use `cpNode.holeCloserTwin.next` to skip the hole closer and get to the
     * next `CpNode` on the same loop.
     */
    readonly holeCloserTwin?: CpNode | undefined;
}
export { CpNode };