public void update() {
        long time = System.currentTimeMillis();
        float delta = time - lastupdate;
        lastupdate = time;
        if (position.getX() > GAME_WIDTH || position.getX() < 0 || position.getY() > GAME_HEIGHT || position.getY() < 0 || schritte >= projectileMaxDistace) {
            Server.projectiles.remove(this);
        } else {
            this.schritte += -xschritt * delta;
            float x = position.getX() - (projectileSpeed * delta) * xschritt;
            float y = x * m + b;
            position.setLocation(x, y);
        }
    }