The part table established vertex_offset + 16 * vertex_count == next_part on
43467 of 43467 parts, which fixes the vertex stride at 16. Autocorrelation
over the spans now reaches the same number without using that result.
Range measured: moby class spans of 16 KB or more on level 0 -- 60 spans,
bounded by consecutive class offsets, over their first 32768 bytes.
Method: peak-stride autocorrelation against a matched control, strides 4 to
64.
stride 16 43 spans
stride 8 8
stride 48 4
stride 32 3
stride 24 2
16 dominates and it is the same 16 the part table produces from a completely
different argument -- a tiling identity over part records rather than a
periodicity measurement over span contents.
Two unrelated methods agreeing is worth more than either alone. The
autocorrelation would be vulnerable to the exact artifacts this project has
already been bitten by: a dominant byte value inflates it, and a period that
happens to divide the measurement window looks identical to a real one.
Neither applies here, and a tiling identity cannot be inflated at all.
This is the strongest form of evidence produced so far in this project -- a
structural invariant confirmed by two methods that do not share a failure
mode.
ReaperOfVeriod
d3373042b9