quatFromEuler.js

function quatFromEuler(roll, pitch, yaw) {
    var c1 = Math.cos(x / 2);
    var c2 = Math.cos(y / 2);
    var c3 = Math.cos(z / 2);
    var s1 = Math.sin(x / 2);
    var s2 = Math.sin(y / 2);
    var s3 = Math.sin(z / 2);

    var x = s1 * c2 * c3 + c1 * s2 * s3;
    var y = c1 * s2 * c3 - s1 * c2 * s3;
    var z = c1 * c2 * s3 - s1 * s2 * c3;
    var w = c1 * c2 * c3 + s1 * s2 * s3;

    return { x, y, z, w };
};