Structure detail levels in checks#

A structure type says how much of the structure its file describes (detail, see Structure libraries):

stick figure — a mast and crossarms to the attachment points, or [[body]] polylines all in one plane (a face);
sticks of the pylon — joints and members without sections, or [[body]] polylines that make a 3D object (their vertices, all together, not in one plane within 1 mm: StructureType::body_is_3d);
full design — every member with its section and a supported joint (or a separate .ohlfe model); extension bodies need the same. Only a joint's support counts (StructureType::missing_for_design): a structure standing only on springs (spring) stays at level 2 today. A pole is a full design when the pole check can read it (a .ohlp named, or a complete [pole]); the higher of the two levels counts.

The level follows from the file's content (StructureType::detail()), so it rises as a pylon is filled in.

Rule for every new check or test whose result depends on the structure's shape (distances to the structure body, insulator swing against the structure, structure analysis, clearances inside the window of a tower, anything reading body, the joints and members, or the .ohlfe model):

before implementing it, decide with the project owner what it does at each level — e.g. not available, an approximation (from the stick figure), or the exact check — and what it reports when a structure's level is too low;
write that behaviour, per level, in the check's documentation and test each level;
a check never silently treats a stick figure as an outline or a full design.

In code the level is ohl_structures::Detail (StructureType::detail()).

Agreed so far: clearances to the structure body — none at level 1 (LiDAR points are a separate topic), computed at levels 2 and 3, the tests to be defined with the project owner.