3.5 Common Lisp terrain generator
=================================

cl-rebonoise (1) is a Common Lisp implementation of the Simplex/Perlin
noise approach described in Amit Patel's 'Making maps with noise
functions' (2).

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Generated terrain.

   Includes primitives and also helper functions, e.g.:
     (grid-to-file 500 500 "./examples/img/7-biome2.png"
                   :coefs '((1 6) (2 11) (4 8) (18 2) )
                   :power 1.45
                   :offset 166
                   :biomes t)

   Amit's page has a wealth of resources on game-related topics, from an
implementation perspective, and I've been following it for years.

3.5.1 Why I'm interested
------------------------

Part of this is because one of my long-term projects is to recreate a
turn-based, play-by-(e)mail game that I was addicted to decades ago (3),
a project I keep coming back to only to get derailed in building more
'infrastructure' instead of actual code: my commits to BKNR, a Common
Lisp in-memory datastore (4) where part of this, and this library
another.

   While I end up getting side-tracked, one of this days I will piece
together all the side quests and make that game available.  Well, that's
the plan, anyway.

   ---------- Footnotes ----------

   (1) cl-rebonoise (https://github.com/fsmunoz/cl-rebonoise)

   (2) Amit Patel's 'Making maps with noise functions'
(https://www.redblobgames.com/maps/terrain-from-noise/)

   (3) It was very a local phenomenon called 'Idade das Trevas' ('Dark
Ages'), and was very popular in the small-but-connected world of
strategy games enthusiasts in the 90s.

   (4) BKNR, a Common Lisp in-memory datastore
(https://github.com/hanshuebner/bknr-datastore)