Vitsas, NickEvangelou, IordanisPapaioannou, GeorgiosGkaravelis, AnastasiosMyszkowski, KarolNiessner, Matthias2023-05-032023-05-0320231467-8659https://doi.org/10.1111/cgf.14758https://diglib.eg.org:443/handle/10.1111/cgf14758Oriented bounding box (OBB) hierarchies can be used instead of hierarchies based on axis-aligned bounding boxes (AABB), providing tighter fitting to the underlying geometric structures and resulting in improved interference tests, such as ray-geometry intersections. In this paper, we present a method for the fast, parallel transformation of an existing bounding volume hierarchy (BVH), based on AABBs, into a hierarchy based on oriented bounding boxes. To this end, we parallelise a high-quality OBB extraction algorithm from the literature to operate as a standalone OBB estimator and further extend it to efficiently build an OBB hierarchy in a bottom up manner. This agglomerative approach allows for fast parallel execution and the formation of arbitrary, high-quality OBBs in bounding volume hierarchies. The method is fully implemented on the GPU and extensively evaluated with ray intersections.CCS Concepts: Computing methodologies -> Ray tracing; Visibility; Mesh geometry modelsComputing methodologiesRay tracingVisibilityMesh geometry models10.1111/cgf.14758245-25410 pages