Debian specific setup
=====================

The `Surface Evolver' front-end comes in different variants that can coexist.

These variants are gathered in flavours, each flavour being distributed within
a distint Debian package. At the time of writing, there are 2 flavours: the
first flavour, the `nox' flavour, is a version the evolver front-end built with
the `Null graphics' module, that is, with literally no X support; the second
flavour, the `ogl' flavour, is compiled with the `OpenGL/GLUT display' module.
Both are built with routines for interfacing with Geomview via a pipe. For each
flavour, there are several variants that deal with distint floating point
formats: the `d' variant crunches `double' floating point numbers; the `ld'
variant calculates with `long double' floating point numbers; and, if supported
by the architecture, the `q' variant reckons with `quadruble' (`float128')
floating point numbers (and it uses the quadmath library for its arithmetic).
The variant suffix appended to each front-end is meant to be self-explanatory.

Information specific to each variant is available within its `banner' which
is displayed as session preamble and available through either its manpage
(BANNER section) or the short option `-V'.

update-alternatives(8) is used to select the default variant: you want to type
	$ update-alternatives --display evolver
to display information about the involved link group.

The paths `/usr/share/doc/evolver/html' and `/usr/share/doc/evolver/examples'
are appended by default (in that order) to the environment variable EVOLVERPATH
which is meant to contain a colon-separated list of paths automatically
searched for datafiles, included files, and on-line help contents (evolver(1)).
The content of these folders is provided within the Debian package evolver-doc,
as expected. This appending default behaviour can be cancelled by appending at
least three consecutive colons (":::") to the environment variable EVOLVERPATH.

Each evolver front-end variant is compiled against the readline(3) library:
the history list is stored in `~/.evolver_history'.

This very README.Debian file is part of the Debian package evolver-nox
which provides the `nox' flavour variants.

 -- Jerome Benoit <calculus@rezozer.net>  Thu, 28 Jul 2016 00:13:11 +0000
