From f5b3024b096b0b16dc6bb9a05aba3582911ae7c7 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Sat, 27 Jul 2019 16:53:47 +0800
Subject: [PATCH] add heart_chain

---
 examples/heart_chain.scad | 101 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 101 insertions(+)
 create mode 100644 examples/heart_chain.scad

diff --git a/examples/heart_chain.scad b/examples/heart_chain.scad
new file mode 100644
index 00000000..5e1a93bd
--- /dev/null
+++ b/examples/heart_chain.scad
@@ -0,0 +1,101 @@
+include <archimedean_spiral.scad>;
+include <arc.scad>;
+
+chars = "3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412737245870066063155881748815209209628292540917153643678925903600113305305488204665213841469519415116094330572703657595919530921861173819326117931051185480744623799627495673518857527248912279381830119491298336733624406566430860213949463952247371907021798609437027705392171762931767523846748184676694051320005681271452635608277857713427577896091736371787214684409012249534301465495853710507922796892589235420199561121290219608640344181598136297747713099605187072113499999983729780499510597317328160963185950244594553469083026425223082533446850352619311881710100031378387528865875332083814206171776691473035982534904287554687311595628638823537875937519577818577805321712268066130019278766111959092164201989";
+
+
+module heart(radius, center = false) {
+    rotated_angle = 45;
+    diameter = radius * 2;
+    
+    module heart_sub_component() {
+        translate([-radius * cos(rotated_angle), 0, 0]) 
+            rotate(-rotated_angle) union() {
+                circle(radius);
+                translate([0, -radius, 0]) 
+                    square(diameter);
+            }
+    }
+    
+    offsetX = center ? 0 : radius + radius * cos(45);
+    offsetY = center ? 1.5 * radius * sin(45) - 0.5 * radius : 3 * radius * sin(45);
+    translate([offsetX, offsetY, 0]) {
+        heart_sub_component();
+        mirror([1, 0, 0]) heart_sub_component();
+    }
+}
+
+module heart_with_ears(heart_width, thickness, spacing) {
+    module ear(radius, thickness, spacing) {
+        width = radius / 1.5;
+        
+        linear_extrude(thickness) 
+            arc(radius, [0, 240], width, "LINE_OUTWARD");
+            
+        translate([0, 0, thickness + spacing]) 
+            linear_extrude(thickness) 	
+                arc(radius, [240, 360], width, "LINE_OUTWARD");
+            
+        linear_extrude(thickness * 2 + spacing) 
+            arc(radius, [0, 20], width, "LINE_OUTWARD");
+    }
+    
+	heart_radius = 0.5 * heart_width / (1 + cos(45));
+	ring_radius = heart_radius / 3;
+	ring_x = (heart_width / 2 + spacing) * 1.075;
+    ring_y = heart_radius * sin(60);
+	ring_thickness = 0.5 * (thickness - spacing);
+	
+	linear_extrude(thickness) 
+	    heart(heart_radius, center = true);
+
+	translate([ring_x, ring_y, 0]) 
+		rotate(-40) 
+		    ear(ring_radius, ring_thickness, spacing); 
+
+	translate([-ring_x, ring_y, 0]) 
+	    rotate(125) 
+		    ear(ring_radius, ring_thickness, spacing);
+}
+
+module text_heart(char, width, thickness, spacing) {
+    radius = 0.5 * width / (1 + cos(45));
+    half_thickness = thickness / 2;
+	difference() {
+		heart_with_ears(width, thickness, spacing);
+		translate([0, 0, half_thickness])
+			linear_extrude(half_thickness) 
+                offset(-half_thickness) 
+                    heart(radius, center = true);
+	}
+	translate([0, radius / 4, half_thickness])
+		linear_extrude(half_thickness)  
+		    text(char, font = "Arial Black", size = radius * 1.2, valign = "center", halign="center");
+}
+
+module heart_chain(chars) {
+    $fn = 48;
+	heart_thickness = 2.5;
+	heart_width = 18;
+	spacing = 0.5;
+	leng = len(chars);
+
+    points_angles = archimedean_spiral(
+        arm_distance = 20,
+        init_angle = 720,
+        point_distance = 23.8,
+        num_of_points = leng 
+    ); 
+    
+    for(i = [0:leng - 1]) {
+        pt = points_angles[i][0];
+        angle = points_angles[i][1];
+        translate(pt)
+            rotate(angle + 90) 
+                text_heart(chars[i], heart_width, heart_thickness, spacing);       
+    }
+}
+
+heart_chain(chars);
+
+