phaser/src/geom/triangle/BuildRight.js

A fast, free and fun HTML5 Game Framework for Desktop and Mobile web browsers from the team at Phaser Studio Inc.

/**
 * @author       Richard Davey <rich@phaser.io>
 * @copyright    2013-2026 Phaser Studio Inc.
 * @license      {@link https://opensource.org/licenses/MIT|MIT License}
 */

var Triangle = require('./Triangle');

//  Builds a right triangle, with one 90 degree angle and two acute angles
//  The x/y is the coordinate of the 90 degree angle (and will map to x1/y1 in the resulting Triangle)
//  w/h can be positive or negative and represent the length of each side

/**
 * Builds a right triangle, i.e. one which has a 90-degree angle and two acute angles. The `x` and `y` coordinates mark the position of the right-angle vertex, which becomes the first point of the Triangle. The `width` and `height` values determine the lengths of the two sides adjacent to the right angle and may be positive or negative, which controls the direction in which each side extends from the right-angle vertex.
 *
 * @function Phaser.Geom.Triangle.BuildRight
 * @since 3.0.0
 *
 * @param {number} x - The X coordinate of the right angle, which will also be the first X coordinate of the constructed Triangle.
 * @param {number} y - The Y coordinate of the right angle, which will also be the first Y coordinate of the constructed Triangle.
 * @param {number} width - The length of the side which is to the left or to the right of the right angle.
 * @param {number} height - The length of the side which is above or below the right angle. If not given, defaults to the value of `width`.
 *
 * @return {Phaser.Geom.Triangle} The constructed right Triangle.
 */
var BuildRight = function (x, y, width, height)
{
    if (height === undefined) { height = width; }

    //  90 degree angle
    var x1 = x;
    var y1 = y;

    var x2 = x;
    var y2 = y - height;

    var x3 = x + width;
    var y3 = y;

    return new Triangle(x1, y1, x2, y2, x3, y3);
};

module.exports = BuildRight;