Re-add line-us & gcode utils

src/heyarne/line_us/gcode.clj

@@ -0,0 +1,76 @@
+(ns heyarne.line-us.gcode
+  "Provides functions to move from geometry types provided by thi.ng to gcode
+  so you can plot them."
+  (:require [thi.ng.geom.core :as g]
+            [thi.ng.geom.types]
+            [thi.ng.geom.vector :as v]
+            [thi.ng.geom.circle :as c])
+  (:import [thi.ng.geom.types Line2 LineStrip2 Circle2]))
+
+(defprotocol GCode
+  "Convert thi.ng.geom types into sequences of GCode to plot them. The GCode
+  instructions are given as a sequence of vectors, where each vector is given
+  as [x y z]."
+  (->gcode [_] [_ r]
+    "Returns G01 movements on the x, y, and z axis. Z is constantly 1000 in the
+     current implementation, but this might change in the future. The optional
+     parameter `r` can be used to adjust the resolution."))
+
+(defn- point-seq->gcode [pts]
+  (let [vertices pts
+        [l-x l-y] (last vertices)]
+    (conj (mapv (fn [[x y]]
+                  [x y 0]) vertices)
+          [l-x l-y 1000])))
+
+(defn gcode-seq->str [gcode-seq]
+  (map (fn [[x y z]]
+         (str "G01 X" x " Y" y " Z" z)) gcode-seq))
+
+(extend-protocol GCode
+  Line2
+  (->gcode
+    ([_] (point-seq->gcode (:points _)))
+    ([_ r] (->gcode _)))
+
+  LineStrip2
+  (->gcode
+    ([_] (point-seq->gcode (:points _)))
+    ([_ r] (->gcode _)))
+
+  Circle2
+  (->gcode
+    ([_] (point-seq->gcode (:points (g/as-polygon _))))
+    ([_ r] (point-seq->gcode (:points (g/as-polygon _ r))))))
+
+(defn scene->gcode
+  "Converts a scene into a sequence of gcode instructions. A scene is an
+  arbitrarily nested vector of geom instances.
+
+  A scene is hiccup like in that each object can be followed by a map of
+  attributes, which can provide addition information about the preceding
+  object."
+  [scene]
+  (loop [[el & rs] scene
+         res []]
+    (cond
+      (seq? el) (recur (scene->gcode el) res)
+      (map? el) (recur rs res)
+      :else (if (seq rs)
+              (recur rs (conj res (gcode-seq->str (->gcode el))))
+              (flatten res)))))
+
+(comment
+  (require '[thi.ng.geom.circle :as c])
+
+  ;; convert a single element
+  (->
+   (->gcode (c/circle) 10)
+   (gcode-seq->str))
+
+  ;; convert a tree of elements
+  (scene->gcode
+   [(c/circle 10)
+    [(c/circle [0 20] 10)
+     (c/circle [0 40] 10)]])
+  )