Galactica, a Digital Planetarium for Immersive Virtual Reality Settings

The authors describe a new Digital Planetarium system and application (“Galactica”), for interactive visualization of astrophysical data and phenomena in immersive virtual reality (VR) settings, based in OpenSceneGraph (OSG). Galactica enables a visual and aural experience of a virtual space traveler, that can go anywhere in the Solar System and the Milky Way at any speed. The application was tested with an available dataset of such scenery, featuring 100 629 textured billboards representing stars and additional 104 328 polygons, representing constellations, orbits, planets and respective moons of the Solar System. The authors have computed the frame rate, GPU traverse time, Cull traverse time and Draw traverse time for three visualization conditions: (A) standard OSG view frustum culling technique; (B) view frustum culling with an octree organization of the scene; (C) view frustum culling with same organization of the scene and the occlusion culling algorithm. They have generally concluded that their acceleration techniques out-performs the standard OSG view frustum culling for the mentioned metrics, when around half or less than half of the dataset is in view of the virtual camera.