Improved two-level BVHs using partial re-braiding

Data Parallel Path Tracing in Object Space

“…In this field, the community has largely switched from spatial techniques to object-space techniques like BVHes [Parker et al 2010;Wald et al 2014;Burgess 2020]. These BVHes are often built using spatially influenced techniques like topdown partitioning and the Surface Area Heuristic (SAH) [Karras and Aila 2013]), and do best when augmented with optimizations like spatial splits [Stich et al 2009;Ganestam and Doggett 2016;Ernst and Greiner 2007] and braiding [Benthin et al 2017]-but they are nevertheless object-space techniques.…”

A Survey on Bounding Volume Hierarchies for Ray Tracing

“…Largely overlapping objects (in world space), which are common in real-world scenarios, can quickly reduce the culling efficiency of the top-level BVH, as a ray intersecting the overlapping region will need to sequentially intersect all overlapping objects. For reducing the overlap, Benthin et al [BWWA17] proposed to apply partial re-braiding. After building an individual BVH for each object, the approach opens and merges bottom-level BVHs during top-level BVH build.…”

“…Hyperion [BAC * 18] and SPI Arnold [KCSG18] support single-level instancing while Autodesk Arnold [GIF * 18] supports multi-level instancing, which allows users to handle even larger scenes. Since overlapping instanced objects lead to performance degradation, Hyperion [BAC * 18] uses a method similar to partial re-braiding [BWWA17] taking into account the solid angle from a camera while generating references for the top-level hierarchy.…”

Efficient BVH‐based Collision Detection Scheme with Ordering and Restructuring

“…During research, we discovered that BVHs have recently been a hot topic in the field of ray tracing. Several GPU-based restructuring techniques aiming for higher ray throughput have been proposed [KA13, DP15,BWWA17]. The key difference between these techniques and our method is the scale of structure for optimization, i.e.…”