Special / Custom Operations

These are exported authored ops outside generic primitive/boolean/surface families.

hole

Typed placeholder op. Use to mark missing geometry intentionally.

• signature: hole :type kind
• signature: hole :type kind :goal "why this hole exists"
• required keyword:
• :type
• optional keyword:
• :goal

Allowed :type values:

• solid
• sketch
• path
• shape

Current behavior:

• compiler accepts it as typed placeholder
• lowerers reject it until replaced with real geometry

compound

• signature: compound shape1 shape2 ...
• groups shapes without boolean merge semantics

helical-ridge

Keyword-only thread-like ridge generator.

• required keywords:
• :radius
• :pitch
• :height
• :base-width
• :crest-width
• :depth
• optional keywords:
• :female
• :clearance
• :lefthand

Example:

(helical-ridge
  :radius 10
  :pitch 2
  :height 18
  :base-width 1.2
  :crest-width 0.4
  :depth 0.7
  :female #t
  :clearance 0.15
  :lefthand #t)

sampled-radial-loft

Procedural sampled shell / loft op.

(sampled-radial-loft
  (theta z fz)
  :height 40
  :z-steps 6
  :theta-steps 24
  :radius expr
  :z-map expr)

• binder list must be exactly (theta z fz)
• required keywords:
• :height
• :z-steps
• :theta-steps
• :radius
• optional keyword:
• :z-map

wall-pattern

Pattern op applied to shell/solid target.

Pattern shape seen in repo:

(wall-pattern
  (:mode gyroid :depth 0.6 :uFreq 4 :vFreq 5 :phase 0.2)
  shape)

Observed options:

• :mode
• :depth
• :uFreq
• :vFreq
• :phase

Observed modes:

• gyroid
• cellular
• fbm
• ribs

Backend caveat:

• native OCCT handles BREP operations; wall-pattern remains mesh-only