phaser/src/math/ToXY.js

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/**
* @author Richard Davey <rich@phaser.io>
* @copyright 2013-2024 Phaser Studio Inc.
* @license {@link https://opensource.org/licenses/MIT|MIT License}
*/
var Vector2 = require('./Vector2');
/**
* Returns a Vector2 containing the x and y position of the given index in a `width` x `height` sized grid.
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*
* For example, in a 6 x 4 grid, index 16 would equal x: 4 y: 2.
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*
* If the given index is out of range an empty Vector2 is returned.
*
* @function Phaser.Math.ToXY
* @since 3.19.0
*
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* @param {number} index - The position within the grid to get the x/y value for.
* @param {number} width - The width of the grid.
* @param {number} height - The height of the grid.
* @param {Phaser.Math.Vector2} [out] - An optional Vector2 to store the result in. If not given, a new Vector2 instance will be created.
*
* @return {Phaser.Math.Vector2} A Vector2 where the x and y properties contain the given grid index.
*/
var ToXY = function (index, width, height, out)
{
if (out === undefined) { out = new Vector2(); }
var x = 0;
var y = 0;
var total = width * height;
if (index > 0 && index <= total)
{
if (index > width - 1)
{
y = Math.floor(index / width);
x = index - (y * width);
}
else
{
x = index;
}
}
return out.set(x, y);
};
module.exports = ToXY;