playcanvas/build/playcanvas/src/core/math/random.d.ts

Open-source WebGL/WebGPU 3D engine for the web

export namespace random {
    /**
     * Return a pseudo-random 2D point inside a unit circle with uniform distribution.
     *
     * @param {Vec2} point - The returned generated point.
     * @example
     * const point = new pc.Vec2();
     * pc.random.circlePoint(point);
     * // point now contains a random position inside a unit circle
     */
    function circlePoint(point: Vec2): void;
    /**
     * Generates evenly distributed deterministic points inside a unit circle using Fermat's spiral
     * and Vogel's method.
     *
     * @param {Vec2} point - The returned generated point.
     * @param {number} index - Index of the point to generate, in the range from 0 to numPoints - 1.
     * @param {number} numPoints - The total number of points of the set.
     * @example
     * const point = new pc.Vec2();
     * for (let i = 0; i < 100; i++) {
     *     pc.random.circlePointDeterministic(point, i, 100);
     *     // point contains the i-th evenly distributed point in the circle
     * }
     */
    function circlePointDeterministic(point: Vec2, index: number, numPoints: number): void;
    /**
     * Generates evenly distributed deterministic points on a unit sphere using Fibonacci sphere
     * algorithm. It also allows the points to cover only part of the sphere by specifying start
     * and end parameters, representing value from 0 (top of the sphere) and 1 (bottom of the
     * sphere). For example by specifying 0.4 and 0.6 and start and end, a band around the equator
     * would be generated.
     *
     * @param {Vec3} point - The returned generated point.
     * @param {number} index - Index of the point to generate, in the range from 0 to numPoints - 1.
     * @param {number} numPoints - The total number of points of the set.
     * @param {number} [start] - Part on the sphere along y axis to start the points, in the range
     * of 0 and 1. Defaults to 0.
     * @param {number} [end] - Part on the sphere along y axis to stop the points, in the range of
     * 0 and 1. Defaults to 1.
     * @example
     * const point = new pc.Vec3();
     * for (let i = 0; i < 100; i++) {
     *     pc.random.spherePointDeterministic(point, i, 100);
     *     // point contains the i-th evenly distributed point on the sphere
     * }
     */
    function spherePointDeterministic(point: Vec3, index: number, numPoints: number, start?: number, end?: number): void;
    /**
     * Generate a repeatable pseudo-random sequence using radical inverse. Based on
     * http://holger.dammertz.org/stuff/notes_HammersleyOnHemisphere.html
     *
     * @param {number} i - The index in the sequence to return.
     * @returns {number} The pseudo-random value.
     * @example
     * // Generate first 4 values of the sequence
     * pc.random.radicalInverse(0); // returns 0
     * pc.random.radicalInverse(1); // returns 0.5
     * pc.random.radicalInverse(2); // returns 0.25
     * pc.random.radicalInverse(3); // returns 0.75
     */
    function radicalInverse(i: number): number;
}
import type { Vec2 } from './vec2.js';
import type { Vec3 } from './vec3.js';