public static void ReloadRooms()
    {
        using (System.IO.StreamReader sr = new System.IO.StreamReader("Rooms.json"))
            {
                GlobalValues.rooms.Clear();
                
                var data = JsonSerializer
                    .Deserialize<JsonReceiver>(
                        sr.ReadToEnd(), 
                        new JsonSerializerOptions { IncludeFields = true }
                    ).ParseData();

                checkpoints = data.Item1;
                rooms = backup_rooms = data.Item2;                
            }
    }

public static void ReloadRooms()
    {
        using (System.IO.StreamReader sr = new System.IO.StreamReader("Rooms.json"))
            {
                GlobalValues.rooms.Clear();
                
                var data = JsonSerializer
                    .Deserialize<JsonReceiver>(
                        sr.ReadToEnd(), 
                        new JsonSerializerOptions { IncludeFields = true }
                    ).ParseData();

                checkpoints = data.Item1;
                rooms = backup_rooms = data.Item2;                
            }
    }

if (position.Length() >= radius)
{
    double ratio = radius / position.Length();
    position *= ratio;

    double collision_angle = Math.Acos(position.X / radius);
    double vector_angle = Math.Atan2(velocity.Y, velocity.X) + Math.PI;
    double new_angle = 2 * collision_angle - vector_angle;
    double vlen = velocity.Length();

    velocity = new Vec2(-Math.Cos(new_angle), Math.Sin(new_angle)) * vlen;
}

if (position.Length() >= radius)
{
    double ratio = radius / position.Length();
    position *= ratio;

    double collision_angle = Math.Acos(position.X / radius);
    double vector_angle = Math.Atan2(velocity.Y, velocity.X) + Math.PI;
    double new_angle = 2 * collision_angle - vector_angle;
    double vlen = velocity.Length();

    velocity = new Vec2(-Math.Cos(new_angle), Math.Sin(new_angle)) * vlen;
}