arcade-physics/lib/geom/triangle/BuildFromPolygon.js

Use Arcade Physics without Phaser.

"use strict";
/**
 * @author       Richard Davey <rich@photonstorm.com>
 * @copyright    2020 Photon Storm Ltd.
 * @license      {@link https://opensource.org/licenses/MIT|MIT License}
 */
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const Earcut_1 = __importDefault(require("../polygon/Earcut"));
const Triangle_1 = __importDefault(require("./Triangle"));
/**
 * Takes an array of vertex coordinates, and optionally an array of hole indices, then returns an array
 * of Triangle instances, where the given vertices have been decomposed into a series of triangles.
 *
 * @function Phaser.Geom.Triangle.BuildFromPolygon
 * @since 3.0.0
 *
 * @generic {Phaser.Geom.Triangle[]} O - [out,$return]
 *
 * @param {array} data - A flat array of vertex coordinates like [x0,y0, x1,y1, x2,y2, ...]
 * @param {array} [holes=null] - An array of hole indices if any (e.g. [5, 8] for a 12-vertex input would mean one hole with vertices 5–7 and another with 8–11).
 * @param {number} [scaleX=1] - Horizontal scale factor to multiply the resulting points by.
 * @param {number} [scaleY=1] - Vertical scale factor to multiply the resulting points by.
 * @param {(array|Phaser.Geom.Triangle[])} [out] - An array to store the resulting Triangle instances in. If not provided, a new array is created.
 *
 * @return {(array|Phaser.Geom.Triangle[])} An array of Triangle instances, where each triangle is based on the decomposed vertices data.
 */
const BuildFromPolygon = (data, holes, scaleX, scaleY, out) => {
    if (holes === undefined) {
        holes = null;
    }
    if (scaleX === undefined) {
        scaleX = 1;
    }
    if (scaleY === undefined) {
        scaleY = 1;
    }
    if (out === undefined) {
        out = [];
    }
    const tris = (0, Earcut_1.default)(data, holes);
    let a;
    let b;
    let c;
    let x1;
    let y1;
    let x2;
    let y2;
    let x3;
    let y3;
    for (let i = 0; i < tris.length; i += 3) {
        a = tris[i];
        b = tris[i + 1];
        c = tris[i + 2];
        x1 = data[a * 2] * scaleX;
        y1 = data[a * 2 + 1] * scaleY;
        x2 = data[b * 2] * scaleX;
        y2 = data[b * 2 + 1] * scaleY;
        x3 = data[c * 2] * scaleX;
        y3 = data[c * 2 + 1] * scaleY;
        out.push(new Triangle_1.default(x1, y1, x2, y2, x3, y3));
    }
    return out;
};
exports.default = BuildFromPolygon;
//# sourceMappingURL=BuildFromPolygon.js.map