Architectural features

I keep spotting bits of buildings and wondering how I can model them.

A staircase

Github. The sector module is a general transformation which takes a angular slice from a 3-D object.

A rope decoration

Github . The basic pattern is an epitrochoid which is linear_extruded with a twist.

A rose window

Github The lack of support for recursion in modules leads to repetition of code.

A colonade

Github The core object is a rounded vault, which with a column is replicated over a grid to produce the colonade. One ambition is to construct the wonderful Mezquita in Cordoba (minus its intrusive cathedral).