Bounding Volume Hierarchy with Bounding Volumes in Prior Space corresponding to Subset of Transform Sub-Tree Bounds

A method, comprising:

• accessing, by a computing system, graphics data that indicates coordinates of primitives in a graphics scene;
• generating, by the computing system based on the graphics data, a bounding volume hierarchy (BVH) acceleration data structure (ADS) that includes:
• a transform node;
• one or more ancestor nodes of the transform node that define bounding volumes in a first coordinate space;
• and
• levels of descendent nodes of the transform node that define bounding volumes in a second coordinate space;
• wherein the one or more ancestor nodes define, in the first coordinate space, one or more first bounding volumes, wherein a given volume of the one or more first bounding volumes:
• is smaller than a bounding volume corresponding to the transform node;
• and
• corresponds to one or more bounding volumes defined at one or more of the levels of the descendent nodes;
• traversing, by the computing system, the ADS, including determining whether to traverse to the levels of descendent nodes based on whether there are any intersections between a ray and bounding volumes defined by the one or more ancestor nodes;
• and
• determining one or more primitives to test for intersection by the ray based on the traversal.

A non-transitory computer-readable medium having instructions stored thereon that are executable by a computing device to perform operations comprising:

• accessing, by a computing system, graphics data that indicates coordinates of primitives in a graphics scene;
• generating, by the computing system based on the graphics data, a bounding volume hierarchy (BVH) acceleration data structure (ADS) that includes:
• a transform node;
• one or more ancestor nodes of the transform node that define bounding volumes in a first coordinate space;
• and
• levels of descendent nodes of the transform node that define bounding volumes in a second coordinate space;
• wherein the one or more ancestor nodes define, in the first coordinate space, one or more first bounding volumes, wherein a given volume of the one or more first bounding volumes:
• is smaller than a bounding volume corresponding to the transform node;
• and
• corresponds to one or more bounding volumes defined at one or more of the levels of the descendent nodes;
• traversing, by the computing system, the ADS, including determining whether to traverse to the levels of descendent nodes based on whether there are any intersections between a ray and bounding volumes defined by the one or more ancestor nodes;
• and
• determining one or more primitives to test for intersection by the ray based on the traversal.