@woosh/meep-engine/src/core/collection/array/array_swap.js

Pure JavaScript game engine. Fully featured and production ready.

import { assert } from "../../assert.js";

/**
 * Swap two sections between arrays, can be used to move elements in the same array
 * @template T
 * @param {T[]|ArrayLike<T>|TypedArray|Uint8ClampedArray|Uint8Array|Uint32Array|Float32Array} a
 * @param {number} a_offset
 * @param {T[]|ArrayLike<T>|TypedArray|Uint8ClampedArray|Uint8Array|Uint32Array|Float32Array} b
 * @param {number} b_offset
 * @param {number} length How many elements should be moved
 * @returns {void}
 *
 * @example
 *  const array = [1, 2, 3, 4, 5];
 *  array_swap(array, 0, array, 2, 1); // array === [4, 2, 3, 1, 5]
 * @example
 *  const array_a = ["hello", "world"];
 *  const array_b = ["foo", "bar"];
 *  array_swap(array_a, 1, array_b, 0, 1); // array_a === ["hello", "foo"], array_b === ["world", "bar"]
 * @example
 *  const array = [1, 2, 3, 4, 5];
 *  array_swap(array, 0, array, 2, 2); // array === [3, 4, 1, 2, 5]
 */
export function array_swap(
    a, a_offset,
    b, b_offset,
    length
) {
    assert.isNonNegativeInteger(a_offset, 'a_offset');
    assert.isNonNegativeInteger(b_offset, 'b_offset');

    for (let k = 0; k < length; k++) {
        const i = a_offset + k;
        const j = b_offset + k;

        const swap = b[j];

        b[j] = a[i];
        a[i] = swap;
    }

}