Area = function (triangle)
{
    var x1 = triangle.x1;
    var y1 = triangle.y1;

    var x2 = triangle.x2;
    var y2 = triangle.y2;

    var x3 = triangle.x3;
    var y3 = triangle.y3;

    return Math.abs(((x3 - x1) * (y2 - y1) - (x2 - x1) * (y3 - y1)) / 2);
}
Returns the area of a Triangle.

@function Phaser.Geom.Triangle.Area
@since 3.0.0

@param {Phaser.Geom.Triangle} triangle - The Triangle to use.

@return {number} The area of the Triangle, always non-negative.