geometry
This module, written by Philippe Ivaldi, provides an extensive set of
geometry routines, including perpendicular
symbols and a triangle
structure. Link to the documentation for the geometry
module
are posted here:
http://asymptote.sourceforge.net/links.html,
including an extensive set of examples,
http://piprim.tuxfamily.org/asymptote/geometry/index.html, and an index:
http://piprim.tuxfamily.org/asymptote/geometry/modules/geometry.asy.index.type.html