SceneJS_math_addVec4s = function(v, s, dest) {
    if (!dest) {
        dest = v;
    }

    dest[0] = v[0] + s;
    dest[1] = v[1] + s;
    dest[2] = v[2] + s;
    dest[3] = v[3] + s;

    return dest;
}
@param v vec4
@param s scalar
@param dest vec4 - optional destination
@return {vec4} dest if specified, v otherwise
@private