Spatial Data Structures for Dynamic Acoustic Virtual Reality

Over the last decades Virtual Reality (VR) technology has emerged to be a powerful tool for a wide variety of applications such as rapid prototyping, evaluation, therapy, or training tasks. For high quality auralizations (in analogy to visualization) of virtual environments, methods of Geometrical Acoustics (GA) are mostly applied to simulate the propagation of sound inside enclosures. By adapting acceleration algorithms such as BSPand Octrees, current implementations can manage the computational load of moving sound sources around a moving receiver in real-time – even for complex scenarios. However, insertion, modification and extraction of geometrical objects are basic operations in many real-world experiences, but hierarchical spatial data structures do not support them efficiently. For this purpose the concept of Spatial Hashing was introduced, which is usually applied to collision detection tests of deformable objects in Computer Graphics. This contribution describes the design, implementation and integration of a dynamic object controller in the real-time room acoustics simulation software RAVEN. By adapting the concept of Spatial Hashing to the simulation algorithms, RAVEN is able to handle geometry modifications in real-time. The performance of the newly implemented data handlingand simulation routines is briefly discussed and compared to that of Brute Force and BSP-based algorithms.