Serial Ray Intersection Testing for Memory-Limited Ray Tracing

The patent segments the hierarchical acceleration structure into multiple levels (e.g., BVH levels) and processes rays through each level sequentially. Instead of loading all geometry data into memory simultaneously, the system divides the scene into coarse-to-fine bounding volume hierarchies, processing only the necessary portions at each level. This segmentation reduces peak memory usage while maintaining intersection testing efficiency.

The patent performs preliminary organization of geometry data into hierarchical acceleration structures before ray tracing begins. Bounding volumes are pre-computed and stored in a hierarchical format, allowing rays to be tested against simplified representations first. This preliminary structuring enables efficient culling of non-intersecting geometry without requiring all detailed geometry to be loaded into memory simultaneously.

The patent segments the set of primitives into hierarchical groups using bounding volumes. Rays are first tested against coarse bounding volumes at upper hierarchy levels, and only if they intersect do they proceed to finer levels. This segmentation creates a culling effect where most primitives are eliminated early without detailed intersection testing, ensuring accuracy for relevant primitives while dramatically reducing total processing time.

The patent applies partial action by testing rays against only the necessary subset of primitives at each hierarchy level rather than all primitives. The hierarchical structure allows the system to perform intersection testing on a partial set of primitives (those within intersecting bounding volumes) at each level, accumulating results as it descends the hierarchy. This approach achieves complete and accurate intersection detection while avoiding excessive testing of obviously non-intersecting primitives.

The patent segments ray request generation into discrete hierarchy levels. At each level, the system generates ray requests only for bounding volumes that are intersected by incoming rays. This segmented approach ensures that ray requests are generated systematically and completely for all relevant geometry while avoiding redundant requests. The hierarchical segmentation provides a natural framework for tracking and managing ray requests without excessive complexity.

The patent implements dynamic ray request management where the number and scope of ray requests adapt based on the hierarchical traversal state. As rays descend through the hierarchy and intersect bounding volumes, new ray requests are dynamically generated for child nodes. This dynamic generation ensures complete intersection detection while automatically adjusting the workload based on scene geometry and ray paths, avoiding static over-provisioning of ray requests.