lable.  See <a href="https://www.khronos.org/webgl/wiki/Getting_a_WebGL_Implementation">How to get a WebGL 2 implementation</a>';
            return;
        }

        // -- Viewport

        var windowSize = {
            x: canvas.width,
            y: canvas.height
        };

        var Views = {
            BOTTOM_LEFT: 0,
            BOTTOM_CENTER: 1,
            BOTTOM_RIGHT: 2,
            MIDDLE_LEFT: 3,
            MIDDLE_CENTER: 4,
            MIDDLE_RIGHT: 5,
            TOP_LEFT: 6,
         