From 091f071cb569b4cd9f25d8c46959714e2c83d5ef Mon Sep 17 00:00:00 2001
From: Justin Lin <justin.sdk@gmail.com>
Date: Tue, 10 Aug 2021 11:34:52 +0800
Subject: [PATCH] add tile_penrose3

---
 src/experimental/tile_penrose3.scad | 75 +++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 src/experimental/tile_penrose3.scad

diff --git a/src/experimental/tile_penrose3.scad b/src/experimental/tile_penrose3.scad
new file mode 100644
index 00000000..38647251
--- /dev/null
+++ b/src/experimental/tile_penrose3.scad
@@ -0,0 +1,75 @@
+use <ptf/ptf_rotate.scad>;
+use <hull_polyline2d.scad>;
+
+// triangle: [type, pa, pb pc], c: false(36) or true(108)
+
+PHI = 1.618033988749895; // golden ratio
+
+n = 12;
+
+a0 = 360 / n;
+a2 = 180 - a0 * 2;
+
+function _subdivide(triangles) = 
+    [
+	    for(tri = triangles)
+		let(
+		    type = tri[0],
+			a = tri[1],
+			b = tri[2],
+			c = tri[3]
+		)
+		each (type ? _sub_a1(a, b, c) : _sub_a0(a, b, c))
+	];
+
+function _sub_a0(a, b, c) =
+    let(p = a + (b - a) / PHI)
+	[[false, c, p, b], [true, p, c, a]];	
+	
+function _sub_a1(a, b, c) =
+    let(
+	    q = b + (a - b) / PHI,
+		r = b + (c - b) / PHI
+	)
+	[[true, r, c, a], [true, q, r, b], [false, r, q, a]];
+
+function _penrose3(triangles, n, i = 0) = 
+    i == n ? triangles :
+	        _penrose3(_subdivide(triangles), n, i+ 1);
+			
+			
+module tile_penrose3(triangles, n) {
+    tris = _penrose3(triangles, n);
+	for(t = tris) {
+		color(t[0] ? "white" : "black")
+			polygon([t[2], t[1], t[3]]);
+		linear_extrude(1)
+		    hull_polyline2d([t[2], t[1], t[3]], .2);
+	}
+}
+
+side = 10;
+
+shape_tri0 = [[0, 0], [side, 0], ptf_rotate([side, 0], a0)];
+triangles = [
+    for(i = [0:n - 1]) 
+	let(t = [for(p = shape_tri0) ptf_rotate(p, i * a0)])
+	i % 2 == 0 ? [false, t[0], t[1], t[2]] : [false, t[0], t[2], t[1]]
+];
+
+tile_penrose3(triangles, 0);
+
+translate([30, 0])
+    tile_penrose3(triangles, 1);
+
+translate([60, 0])
+    tile_penrose3(triangles, 2);
+
+translate([0, -30])
+    tile_penrose3(triangles, 3);
+
+translate([30, -30])
+    tile_penrose3(triangles, 4);
+
+translate([60, -30])
+    tile_penrose3(triangles, 5);
\ No newline at end of file