I think in primitive partitioning image the right bounding box is wrong. Its left side should pass the left-most vertex of the bottom triangle. Am I right or I misunderstand something here?

@yongchi1 In this example, the small blue triangle on the far left is contained in both bounding boxes.

I'm having a bit of trouble intuitively grasping the difference between primitive partitioning and space-partitioning---for the former, we split primitives into groups, and for the latter, we spilt space into regions, then assign primitives to regions. I don't really see how these offer advantages, since for both we're checking whether a ray intersects some box, and if it does, then we have to check whether the ray intersects each inner box or primitive.

So that means the small blue triangle is contained by left bounding box, but not actually belongs to it? I think the two sets should be disjoint

@yongchi1 I am pretty sure that's what it means since sets overlap space-wise but their triangles are disjoint.