Exploding dragon benchmark: Three images are shown from a dynamic simulation of a bunny breaking a dragon. This scene consists of 252K triangles and undergoes drastic topological changes. We use our algorithm to selectively restructure an axis-aligned bounding box (AABB) tree during each frame. Our ray tracing algorithm based on selective restructuring is able to achieve 65%--1000% performance improvement over prior ray tracing algorithms that are based on AABB-trees.

Basic restructuring operation: Our algorithm selects a node pair (n_1, n_2), whose BVs overlap considerably (show on the left). Our restructuring operations takes the union of primitives contained in sub-BVH(n_1) and sub-BVH(n_2), re-partitions the primitives into two new nodes, \hat{n_1} and \hat{n_2}, and recursively process the sub-BVHs of the new nodes. The complexity of this operation is O(k \log k), where k = |n_1|_{tri} + |n_2|_{tri}. This is in contrast with other restructuring algorithms where k = |n_A|_{tri}, where n_A is the lowest common ancestor of n_1 and n_2.