Abstract: Octree is a kind of hierarchy structure, and is often used to accelerate ray tracing. In order
to speed up the process of ray tracing, a method which used octree neighbor finding to improve the
speed of collision detection between ray and octree nodes is provided. This method proposes a octree
neighbor finding algorithm which has simple structure and high computational efficiency. Using this
algorithm, the next collision node can be calculated by current collision node quickly, which
improves the image rendering speed. The experimental results show that the efficiency increased at
least 3 times if the collision detection using the neighbor finding rather than the traditional algorithm,
and the proposed algorithm can greatly accelerate the ray tracing.

Key words: ray tracing, octree, neighbor finding, acceleration algorithm