import { vec2 } from "gl-matrix";
/**
 * Rotates each vector in an array by a rotation angle in radians around an origin point.
 *
 * @param base The vectors to apply the rotation to
 * @param origin The origin to rotate the vectors around
 * @param rotation The rotation (in radians) to apply to each vector
 * @returns The rotated vectors
 */
export declare function applyRotation(base: vec2[], origin: vec2, rotation: number): vec2[];
/**
 * Translates each vector in an array by a given translation vector
 *
 * @param base The vectors to apply the translation to
 * @param translation The translation to apply to each vector
 * @returns The translated vectors
 */
export declare function applyTranslation(base: vec2[], translation: vec2): vec2[];
/**
 * Calculates the triple product of three 2D vectors.
 *
 * This is done by:
 *    - extending each 2D vector into 3D by giving them a Z value of 0.
 *    - Calculating the cross product of **A** and **B**, storing the result as vector **R₁**.
 *      **R₁** will be a vector purely in the z axis as the x and y components after the cross product are 0.
 *    - The cross product of **R₁** and **C** is then calculated, we'll call this **R₂**.
 *      **R₂** will be a vector that is perpendicular to **C** and pointing in the direction of **B**.
 *
 * @see [This post for an explanation](https://stackoverflow.com/questions/44797996/triple-product-in-2d-to-construct-perpendicular-line)
 *
 * @param a Initial vector
 * @param b Vector that the result will be in direction of
 * @param c Vector that the result will be perpendicular to
 */
export declare function tripleProduct(out: vec2, a: vec2, b: vec2, c: vec2): vec2;
/**
 * Calculates the cross product of **a** with a scalar and stores the value in **out**
 *
 * @param out The vector to output to
 * @param a The vector to cross
 * @param scalar The scalar to cross a with
 * @returns out
 */
export declare function cross2DWithScalar(out: vec2, a: vec2, scalar: number): vec2;
/**
 * Calculates the cross product of 2 2D vectors and returns the Z value of the resulting 3D vector.
 *
 * @param a The vector to cross
 * @param b The vector to cross with **a**
 * @returns The Z coordinate of the resultant 3D vector
 */
export declare function cross2D(a: vec2, b: vec2): number;
/**
 * Calculate the midpoint between two vectors.
 *
 * @param out The vector to output the result to
 * @param a The start vector
 * @param b The end vector
 * @returns The resultant vector, `out`
 */
export declare function midpoint(out: vec2, a: vec2, b: vec2): vec2;
/**
 * Determines wether two vectors are roughly equal to each other.
 *
 * @param a The first vector
 * @param b The second vector
 * @param xSlop The allowed x slop
 * @param ySlop The allowed y slop
 * @returns Wether the vectors are equal or not
 */
export declare function vec2SloppyEquals(a: vec2, b: vec2, xSlop: number, ySlop: number): boolean;