In this paper, we propose a new approach to building a scalable virtual environment by combining virtual sub-environments. To manage different types of users interaction, datasets, rendering methods, and soforth, we build and handle virtual sub-environments separately. To unify these sub-environments, we propose a use of an environment manager, which determines the users viewpoint of sub-environments according to the user’s input, and compose display image from rendered images of them. By using the proposed methodology, we can combine sub-environments seamlessly, and build a virtual environment to manage different types of datasets, users interaction and rendering methods. By unifying sub-environments according to the user’s viewpoint, we can construct a universal large-scale environment: the user can walk through cities, observe from above the earth, and fly through the solar system.