I recorded the static coupling search as exhausted and needing PE code. The PE
work was done on auto/regn-reader and it solved the whole thing: REGN is a
tetrahedral navigation mesh, reached via the POF0 fixup table -- the loader's own
list of which words are pointers, so nothing needed guessing. Six sections;
position -> cell -> 32-byte item -> tet refs -> tetrahedron, with section 2 a
face carrying a plane plus its 3 vertices and the two tets either side.
Controlled checks: face through 3 of 4 tet vertices 253722/253722 against a
0.07-2.2% random control; portal cost equals face-centroid distance
380460/380460.
Also records against myself that the base is chunk+0x10 and my offsets here were
16 bytes early, that the plane arithmetic survives only because those fields
landed on the same bytes, and that my points-in-bbox count was never evidence --
a shift inside a homogeneous f32 array yields other floats from the same array.
Leaving the wrong conclusion in the backlog would have told the next reader the
avenue was closed when it was the one that worked.
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