@technobuddha/library/angleDifference/angleDifference.cjs

A large library of useful functions

"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.angleDifference = void 0;
var normalizeAngle_1 = __importDefault(require("../normalizeAngle"));
/**
 * Computes the difference between startAngle and endAngle (angles in radians).
 *
 * @param startAngle Start angle in radians.
 * @param endAngle End angle in radians.
 * @returns The number of radians that when added to *startAngle* will result in *endAngle*.
 *
 * @remarks
 * Positive numbers mean that the
 * direction is clockwise. Negative numbers indicate a counter-clockwise direction.
 * The shortest route (clockwise vs counter-clockwise) between the angles is used.
 * When the difference is PI radians, the function returns PI (not -PI)
 *
 * @example
 * angleDifference(PI * 1/6,  PI * 2/6) is PI * 1/6
 *
 * angleDifference(PI * 2/6, PI * 1/6)  is -PI * 1/6.
 *
 * angleDifference(PI * 11/6, PI * 1/6) is PI * 2/6
 *
 * angleDifference(PI * 1/6, PI * 11/6) is -PI * 1/6.
 */
function angleDifference(startAngle, endAngle) {
    var d = normalizeAngle_1.default(endAngle) - normalizeAngle_1.default(startAngle);
    if (d > Math.PI)
        d -= Math.PI * 2;
    return d;
}
exports.angleDifference = angleDifference;
exports.default = angleDifference;