import { Vec3 } from '../../types/common';
/**
 * Interface for interpolating points on a 3d curve
 */
export interface Curve3D {
    getPointAt: (pos: number) => Vec3;
    getPoints: (nSamples: number, from?: number, to?: number) => Vec3[];
    getTangentAt: (pos: number) => Vec3;
    getNormalAt: (pos: number) => Vec3;
    getBoundingBox: (from?: number, to?: number) => {
        min: Vec3;
        max: Vec3;
    };
    nearest: (point: Vec3) => {
        position: number;
        point: Vec3;
        distance: number;
    };
    length: number;
    closed: boolean;
}
/**
 * Returns an implementation of `SplineCurve` using `CurveInterpolator`
 **/
export declare function getSplineCurve(points: Vec3[], closed?: boolean): Curve3D | null;
export type FrenetFrame = {
    curvePosition: number;
    position: Vec3;
    tangent: Vec3;
    normal: Vec3;
    binormal: Vec3;
};
/**
 * Calculate a stable and balanced set of Frenet Frames for a curve at the
 * specified positions.
 */
export declare function calculateFrenetFrames(curve: Curve3D, curvePositions: number[]): FrenetFrame[];
/**
 * Get a set of positions along a curve according to a number of segments per meter,
 * optionally simplified/optimized by specifying a simplification threshold.
 *
 * To get a sub section, use the from and/or to parameters.
 *
 * @remark segments per meter is always calculated from the start of the curve to ensure alingment when optimizing the number of vertices
 */
export declare function getCurvePositions(curve: Curve3D, from?: number, to?: number, segmentsPerMeter?: number, simplificationThreshold?: number): number[];