This shader gets called and will construct ANV BVH from IR BVH. More
specifically, each invocation will take care of one internal node. The
internal nodes get processed starting from root node all the way to the
bottom leaves.
During processing, we keep track of the destination of
where the internal node should be encoded (tracked in
vk_ir_box.bvh_offset), and where its leaves should be encoded (tracked
in vk_ir_header.dst_node_offset).
The processed bvh is in contiguous memory, which starts with header,
followed by interleaving internal nodes and leaves. The nodes
information are also populated.
Rework: (Sagar)
- Return out of bounds threads early
- Mimic GRL internal node encoding
- Handle node mask
- Fix block_incr_and_start_prim
- Fix shader_index_and_geom_mask for instance node
- Fix instance flag
- Fix block_incr and instance_contribution_and_geom_flags initialized to be zero
- Fix lower_x and upper_x to be properly flipped for invalid child
- For invalid node, clear blockIncr and set startPrim to INVALID
- Calculated things upfront and assign, cutting down more than ~200
instructions
Co-authored-by: Kevin Chuang <kaiwenjon23@gmail.com>
Co-authored-by: Sagar Ghuge <sagar.ghuge@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31588>
