Creating Immersive Virtual Environments Based on Open Geospatial Data and Game Engines

Abstract Modern game engines like Unity allow users to create realistic 3D environments containing terrains as well as natural and artificial objects easily and swiftly. In addition, recent advances of game engine capabilities enable effortless implementation of virtual reality (VR) compatibility. 3D environments created with VR compatibility can be experienced from an egocentric and stereoscopic perspective that surpasses the immersion of the ‘classical’ screen-based perception of 3D environments. Not only game developers benefit from the possibilities provided by game engines. The ability to use geospatial data to shape virtual 3D environments opens a multitude of possibilities for geographic applications, such as construction planning, spatial hazard simulations or representation of historical places. The multi-perspective, multimodal reconstruction of three-dimensional space based on game engine technology today supports the possibility of linking different approaches of geographic work more closely. Free geospatial data that can be used for spatial reconstructions is provided by numerous national and regional official institutions. However, the file format of these data sources is not standardized and game engines only support a limited number of file formats. Therefore, format transformation is usually required to apply geospatial data to virtual 3D environments. This paper presents several workflows to apply digital elevation data and 3D city model data from OpenStreetMap and the Open.NRW initiative to Unity-based 3D environments. Advantages and disadvantages of different sources of geospatial data are discussed. In addition, implementation of VR compatibility is described. Finally, benefits of immersive VR implementation and characteristics of current VR hardware are discussed in the context of specific geographic application scenarios.