Disclose how much of the sphere a mesh covers - #129
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A 5-degree mesh spanning 0-40E/0-40N with sphere_radius 6371000.0 returned
total_area 22936016715559.137 m^2 -- 4.4967% of 4*pi*R^2 -- with
scientific_status complete, physically_interpretable true, no warning code,
and a bare postconditions {status: not_evaluated, checks: []}. The identical
call on a global mesh returned 1.0000 of the sphere with the same status
shape. Nothing in either payload said which was which.
calculate_area and inspect_mesh now both carry a mesh_coverage block:
sphere_fraction, closed, euler_characteristic, lon_extent, lat_extent. A
patch raises MESH_NOT_GLOBAL and drops to warning but stays interpretable,
because the area of a patch is a real physical quantity and only the missing
disclosure was wrong.
Geometry and topology are reported separately and are allowed to disagree. A
1-degree structured global grid stops half a cell short of each pole, so it
reads sphere_fraction 0.999963 with closed false and 720 boundary edges;
both facts are true and a single globality verdict would have to suppress
one. Counting edge incidences is a Python loop -- 1.43 s at 196,608 faces,
5.99 s at 786,432 -- so above 250,000 faces the topological half is skipped
and closed comes back null with topology_skipped giving the reason, never
false.
An abstained postcondition now says why. The area identity holds only on a
closed mesh, so a regional result was indistinguishable from a deployment
running verdict_policy off. postcondition_block carries
not_evaluated_because when the server can name a reason, read off
mesh_coverage so naming it costs no second traversal.
mesh_is_closed and _canonical_node_ids move from postconditions to the new
domain module; postconditions reuses the already-computed block and falls
back to counting only for a remote worker on an older build that sends no
coverage. Payload budgets rise 1150 -> 1300 and 1800 -> 1950 for the 151
bytes the block costs, after trimming it: the raw steradian sum is dropped
(it is 4*pi * sphere_fraction) and floats round to 1e-6, which is 510 km^2
of sphere and 0.1 m of arc.
Closes #33
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A 5-degree mesh spanning 0-40E/0-40N with
sphere_radius: 6371000.0returnedtotal_area: 22936016715559.137 m^2(4.4967% of4*pi*R^2) withscientific_status: complete, no warning code, and a barepostconditions: not_evaluated, and the identical call on a global mesh returned 1.0000 of the sphere with the same status shape.calculate_areaandinspect_meshnow carry amesh_coverageblock (sphere_fraction,closed,euler_characteristic,lon_extent,lat_extent); a patch raisesMESH_NOT_GLOBALand drops towarningbut stays interpretable, and an abstained postcondition carriesnot_evaluated_because. Geometry and topology are reported separately because they can honestly disagree (a 1-degree grid reads 0.999963 andclosed: false), and above 250,000 faces the topological half is skipped withtopology_skippedrather than guessed.Closes #33