import { Color, Position } from "./types";
export declare const lerp: (x: number, y: number, a: number) => number;
export declare const clamp: (a: number, min?: number, max?: number) => number;
export declare const invlerp: (x: number, y: number, a: number) => number;
export declare const range: (x1: number, y1: number, x2: number, y2: number, a: number) => number;
/**
 * Get random number between range [min, max].
 * @param min
 * @param max
 * @returns
 */
export declare const randomInRange: (min: number, max: number) => number;
/**
 * Collection of utilities for `{ x: number, y: number }` data structures.
 */
export declare const vec2: {
    /**
     * Subtract two vectors.
     * @param a     Vector
     * @param b     Position
     * @return      `{ x: a.x - b.x, y: a.y - b.x }`
     */
    subtract: (a: Position, b: Position) => Position;
    /**
     * Multiply vector with a number.
     * @param a     Vector
     * @param b     Number
     * @return      `{ x: a.x * b, y: a.y * b }`
     */
    multiply: (a: Position, b: number) => Position;
    /**
     * Get length of vector.
     * @param v     Vector
     * @return      Length of vector
     */
    length: (v: Position) => number;
    /**
     * Get normalized vector.
     * @param v     Vector
     * @returns     Normalized vector (same direction but length = 1).
     */
    normalize: (v: Position) => Position;
};
/**
 * Interpolate between two colors.
 *
 * The color interpolation is done linearly in LAB color space.
 *
 * @param   a       Color 1.
 * @param   b       Color 2.
 * @param   factor  Ratio between colors 1 and 2 that will be used for the returned color.
 * @returns         Interpolated Color.
 */
export declare const lerpColor: (a: Color, b: Color, factor: number) => Color;