add lsystem3_collection

examples/lsystem3_collection.scad

@@ -0,0 +1,32 @@
+use <experimental/lsystem3.scad>;
+use <hull_polyline3d.scad>;
+
+for(line = tree()) {
+    hull_polyline3d(
+        [line[0], line[1]], 
+        thickness = 0.25, 
+        $fn = 4
+    );
+}  
+
+function tree(n = 5, angle = 22.5, leng = 1, heading = 0, start = [0, 0, 0]) = 
+    let(
+        axiom = "A",
+        rules = [
+            ["A", "F[&FLA]/////[&FLA]///////[&FLA]"],
+            ["F", "/////F"]
+        ]
+    )
+    lsystem3(axiom, rules, n, angle, leng, heading, start);  
+
+function hilbert_curve(n = 3, angle = 90, leng = 1, heading = 0, start = [0, 0, 0]) = 
+    let(
+        axiom = "A",
+        rules = [
+            ["A", "B-F+CFC+F-D&F∧D-F+&&CFC+F+B//"],
+            ["B", "A&F∧CFB∧F∧D∧∧-F-D∧|F∧B|FC∧F∧A//"],
+            ["C", "|D∧|F∧B-F+C∧F∧A&&FA&F∧C+F+B∧F∧D//"],
+            ["D", "|CFB-F+B|FA&F∧A&&FB-F+B|FC//"]
+        ]
+    )
+    lsystem3(axiom, rules, n, angle, leng, heading, start);