kernelcad-features

kernelCAD — edge and face features

Face refs through operations

Canonical face refs ({ face: 'top' }, etc.) work transparently across transforms (.translate, .rotate, .scale, .reflect, .mirror) and unambiguous booleans (.subtract, .union, .intersect). The kernel walks each face's lineage back to its originating primitive and forward through history.

Two cases produce explicit diagnostics:

• feature.face-ref.ambiguous-after-split — an upstream boolean split the named face into multiple children (e.g., a divider cut splits top into two halves). Geometry-fallback disambiguation is planned for a future release; current workaround: apply the edge/face feature before the splitting operation, or use a query-based selector.
• feature.face-ref.removed — an upstream boolean removed the named face entirely. Reference a different face that still exists in the current shape.
• feature.hole.no-target-face — the hole entry face matched, but no body sits along the bore axis to drill into. Pick an entry face on a different body, or verify the target body extends along the bore axis.
• feature.created-ref.fallback-used — warning (not error). The created-ref resolver fell back to a geometry-snapshot match after the topology lookup lost the face. The downstream feature still resolves. Lock the ref against future edits by naming the upstream feature with .name() and addressing it by <name>.<slot>.

(The same feature.face-ref.* codes apply to both edge features (fillet, chamfer) and face features (shell).)

Created face refs

Subtractive features (hole, cutout) write created face refs that downstream ops can address by <featureName>.<slot>:

const plate = box(100, 60, 5)
  .hole('top', { u: 0, v: 0, diameter: 6, depth: 3, name: 'pilotHole' });

plate.fillet(0.2, { face: 'pilotHole.floor' });

Slots written by hole: wall, floor, wall-back, counterbore-wall, counterbore-floor, countersink-cone, entry-rim, floor-rim, wall-back-rim. Slots written by cutout: see cutoutClassifier.