Module sweep 

Sweeping: dragging a shape through space to make one of higher dimension.

A vertex sweeps into an edge, an edge into a face, a wire into a shell, a face into a solid. One rule, applied at every level, which is why a prism over a face falls out of the prism over its edges rather than being built separately.

The top is the bottom, moved

The far end of a prism is not a copy of the near end. It is the same topology node at a different Location, the shape triple’s whole reason for existing (docs/DATA_MODEL.md §2). A copy would double the geometry, and then a later edit would have to find and fix both. Sharing means the two ends of a prism cannot drift apart, because there is only one of them.

It also means an assembly of a thousand identical extrusions holds one profile and a thousand placements, which is the case the location chain was designed for.

History

A swept edge is both consumed and generative: it survives as the bottom of the prism and it generates the lateral face. Recording only one of those is the classic way to break downstream naming: a reference to “that edge” resolves to nothing, or a reference to “the face from that edge” does.

Modules

roles

Roles a sweep assigns.

Functions

make_prism

Extrude a shape along vector.

make_prism_tapered

Sweep a planar face into a tapered prism: every wall leans by taper.

make_revolution

Revolve a shape about axis, through angle radians.