reinlined snek

snek/README.md

@@ -0,0 +1,89 @@
+# SNEK is Not an Acronym
+
+![head](img/img.png?raw=true "head")
+
+## About
+
+`snek` is a simple data structure for working with vertices and edges. More
+importantly it is a programming pattern for applying changes to the structure.
+It is specifically written to be useful for a broad range of ways in which i
+usually write generative algorithms for creating art.
+
+The pattern depends on the concept of `alterations`. In short: an `alteration`
+is a change that will be applied to the structure at the end of a given
+context. `alterations` are further described in
+http://inconvergent.net/snek-is-not-an-acronym/.
+
+Here is and example of manipulating a `snek` instance called `snk` using
+`alterations`:
+
+    ; context start
+    (with-snek (snk)
+      ; iterate
+      (with-all-verts (snk v)
+        ; move alteration
+        (move-vert v (rnd-in-circ))
+        ; w will be an arbitrary
+        ; vertex in snk
+        (with-rnd-vert (snk w)
+          ; join v and w if they are closer than d
+          (if (< (vert-dst snk (v w)) d)
+            ; join vertices alteration
+            (join-verts v w))))
+    ; context end
+    ; alterations have been applied
+
+There are two more examples. They can be executed like this:
+
+    ./run-slope.lisp res/slop.png
+    ./run-lines.lisp res/lines.png
+
+Notice that the resulting image will end up in `res`.
+
+`snek` is used in
+
+  - http://moment.inconvergent.net/
+  - https://twitter.com/sandpaintbot
+  - https://twitter.com/scratchpaintbot
+
+## Dependencies
+
+This code requires `Quicklisp` and `zpng`. Note that the The path to quicklisp
+must be set in `src/load`. `zpng` is automatically installed via `quicklisp`.
+
+ - http://www.xach.com/lisp/zpng/
+ - https://www.quicklisp.org/beta/
+
+
+## Run tests
+
+There are some tests included. Run them like this:
+
+    ./run-test.lisp
+
+
+## Stability changes and Versioning
+
+This code is highly experimental on my part. It is likely to change with no
+warning or explanation. I will keep a note of the version number in `VERSION`.
+
+
+## On Use and Contributions
+
+This code is a tool that I have written for my own use. I release it publicly
+in case people find it useful. It is not however intended as a
+collaboration/Open Source project. As such I am unlikely to accept PRs, reply
+to issues, or take requests.
+
+
+## Todo
+
+ - Randomized order of alteration apply
+ - Maintain list of singly-connected vertices?
+ - zonemaps? kd-tree?
+
+
+## Done
+
+ - Reject/attract force move alterations, or force calc funcs? (sort of)
+