DistanceBetween = function (x1, y1, x2, y2)
{
    var dx = x1 - x2;
    var dy = y1 - y2;

    return Math.sqrt(dx * dx + dy * dy);
}
Calculate the distance between two sets of coordinates (points).

@function Phaser.Math.Distance.Between
@since 3.0.0

@param {number} x1 - The x coordinate of the first point.
@param {number} y1 - The y coordinate of the first point.
@param {number} x2 - The x coordinate of the second point.
@param {number} y2 - The y coordinate of the second point.

@return {number} The distance between each point.