Thicken

Status: Implemented

Thicken feature dialog

Thicken converts one or more selected open faces into individual closed solids by offsetting each face along its local normals and stitching side walls around every boundary loop.

Inputs

  • face – one or more face selections. Sketch selections that resolve to a face are also accepted.
  • distance – signed thickness along the face normals. Must be non-zero.
  • id – optional identifier used as the result name for a single face, or as the prefix for multi-face outputs.

Behaviour

  • Resolves each selection to a FACE object, deduplicating repeated picks.
  • Calls face.thicken(distance, { featureId, name }) for each resolved face.
  • Produces one new solid per selected face and leaves the source geometry untouched.
  • Stores per-result diagnostics in feature persistentData and on each returned solid under __thickenDiagnostics and userData.thicken.

Result Naming

  • Single-face thickens use the feature ID as the solid name.
  • Multi-face thickens generate one solid per face using <featureId>_<index>_<sourceFaceName>.
  • Kernel face labels follow the source face name:

- <sourceFaceName>_START for the original-side cap - <sourceFaceName>_END for the offset cap - <sourceFaceName>_SW for the first side wall loop - <sourceFaceName>_L<n>_SW for additional side wall loops

Notes

  • Positive and negative distances are both supported.
  • Faces with holes generate one side wall per boundary loop.
  • Curved faces are supported; the output remains a closed manifold solid when the kernel can classify and stitch the shell successfully.
  • Each selected face becomes its own solid. This feature does not merge multiple thickened faces into one body.
  • Source face metadata is propagated onto the generated start/end cap faces when available.

Related Kernel API

  • UI feature implementation: src/features/thicken/ThickenFeature.js
  • Face method entrypoint: Face.thicken(distance, options) in src/BREP/Face.js
  • Kernel implementation: thickenFaceToSolid(face, distance, options) in src/BREP/faceThicken.js

Covered Scenarios

The test suite currently covers:

  • planar sketch profiles
  • profiles with holes
  • curved cylindrical side faces
  • planar faces with filleted boundaries
  • negative-distance/self-overlap cases
  • partial torus side faces
  • feature serialization and replay
  • multi-face output naming and persistence

See src/tests/test_thickenFeature.js for executable examples of the current behavior.