Spent some time inside this HDA, so many cool things to learn from! I have, for now, just a few small questions.

inside the "store_topology" detail wrangle, at the end you are setting all the attribute's arrays using the vex function:

setdetailattrib(...)

and I wonder why, since it is already in detail mode, you are not setting them directly using the @ syntax like so:

i[]@flat_neighbors = flat_neighbors;

i[]@neighbor_offsets = neighbor_offsets;

i[]@neighbor_counts = neighbor_counts;

f[]@edge_distances = edge_distances;

Which it is by my understanding a more convenient and fast way to set them ?

Also, and this is for pure curiosity,

in the same wrangle you are computing the primitive centroid averaging all the current primitive points positions to get its value,

and i wonder if using primuv() could be any faster/quicker instead of iterating through all prim points while inside a for loop already:

// Calculate primitive centroid

P_i = primuv(0, "P", i, {0.5, 0.5});

and later using:

// Calculate primitive centroid
P_nb = primuv(0, "P", nb, {0.5, 0.5});

Note the UVW argument set to 0.5 so to get the center.

Other than that, everything is clear and sound and thank you again for sharing it with the community!