Module external_ref 

External-reference edges (S6b-2) — link a picked 3D solid edge into the sketch as a construction reference.

The pickEdges tool projects a scene edge’s world-space polyline into the active sketch plane, classifies the projected shape (straight → line, a fitted circle → circle/arc, else a faithful line-chain fallback), and materializes it as external-reference geometry: {fixed, construction, externalReference} points, a ⏚ GROUND constraint per point (so the solver pins them), and the construction geometry referencing them. A per-session ExternalRef mapping (keyed by edge name) dedups a re-pick — the SAME edge UPDATES its points’ coordinates instead of duplicating — and round-trips through persistentData.externalRefs.

This mirrors #ensureExternalRefForEdge/#projectWorldToUV, extended to also emit the reference GEOMETRY (the previous version stored only the two endpoints) so the linked edge is visible and constrainable in the sketch.

Structs

ExternalRef

A per-session external-reference mapping: the linked scene edge (by name + owning solid) and the sketch entities materialized for it. Persisted to / loaded from persistentData.externalRefs so a linked edge round-trips a commit + re-enter.

Enums

EdgeLink

The classification of a projected edge polyline, in plane (u, v) coordinates.

Functions

add_external_ref

Materialize an EdgeLink into the doc: push external-ref points (fixed, construction, externalReference) with a ⏚ ground each, then the construction geometry referencing them. Returns (point_ids, geom_ids).

classify_uv

Classify a projected polyline (in plane (u, v)) as a straight line, a circle / arc, or a polyline fallback. Tolerances are RELATIVE to the polyline’s extent so the same thresholds work at any sketch scale:

link_or_update

Link (or update) a picked scene edge into the sketch as an external reference.

project_polyline

Project a world-space polyline into the plane’s (u, v) frame (orthogonal projection; the off-plane component is dropped). Mirrors the previous world→UV projection applied per vertex.