From 3bbed7e8c0d058d43c45b688e8b55d4077a5be3f Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Thu, 13 Feb 2020 17:19:46 +0800
Subject: [PATCH] add arc_tiled_lines

---
 examples/arc_tiled_lines.scad | 40 +++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 examples/arc_tiled_lines.scad

diff --git a/examples/arc_tiled_lines.scad b/examples/arc_tiled_lines.scad
new file mode 100644
index 00000000..4a976098
--- /dev/null
+++ b/examples/arc_tiled_lines.scad
@@ -0,0 +1,40 @@
+use <util/rand.scad>;
+use <hull_polyline2d.scad>;
+use <arc.scad>;
+use <experimental/tf_ring.scad>;
+
+module arc_tiled_lines(size, angle, step, line_width = 1) {
+    sizexy = is_num(size) ? [size, size] : size;
+    s = is_undef(step) ? line_width * 2 : step;
+ 
+    function rand_diagonal_line_pts(x, y, size) = 
+        rand(0, 1) >= 0.5 ? [[x, y], [x + size, y + size]] : [[x + size, y], [x, y + size]];
+        
+    lines = [
+        for(x = [0:s:sizexy[0] - s]) 
+            for(y = [0:s:sizexy[1] - s]) 
+                rand_diagonal_line_pts(x, y, s)
+    ];
+    
+    for(line = lines) {
+        pts = [for(p = line) tf_ring(size, p, size[0], angle)];
+        hull_polyline2d(pts, width = line_width);
+    }
+    
+    arc_width = line_width * 2;
+    arc(radius = size[0], angle = angle, width = arc_width, $fn = 36);
+    arc(radius = size[0] * 2, angle = angle, width = arc_width, $fn = 36);
+    
+    if(angle != 360) {
+        hull_polyline2d([[size[0], 0], [size[0] * 2, 0]], width = arc_width);
+        rotate(angle) 
+            hull_polyline2d([[size[0], 0], [size[0] * 2, 0]], width = arc_width);        
+    }
+}
+
+size = [20, 100];
+line_width = .5;
+step = 1; 
+angle = 360;
+
+arc_tiled_lines(size, angle, step, line_width);