From f29e410654e1c21c5fc7c0ad989fb1bb8aef0f45 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Tue, 24 Sep 2019 13:44:02 +0800
Subject: [PATCH] add box

---
 .../triangle2square/triangle2square_box.scad  | 86 +++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 examples/triangle2square/triangle2square_box.scad

diff --git a/examples/triangle2square/triangle2square_box.scad b/examples/triangle2square/triangle2square_box.scad
new file mode 100644
index 00000000..5c8da499
--- /dev/null
+++ b/examples/triangle2square/triangle2square_box.scad
@@ -0,0 +1,86 @@
+include <line2d.scad>;
+include <hollow_out.scad>;
+include <box_extrude.scad>;
+include <triangle2square.scad>;
+
+tri_side_leng = 100;
+height = 30;
+spacing = 0.4;
+ring_width = 1.5;  
+shaft_r = 1;  
+    
+module triangle2square_box(type, tri_side_leng, height, spacing, ring_width, shaft_r) {
+	half_tri_side_leng = tri_side_leng / 2;
+    half_h = height / 2;
+
+    joint_ring_inner = shaft_r + spacing;
+    joint_ring_outer = joint_ring_inner + ring_width;
+	joint_r_outermost = joint_ring_outer + spacing;
+
+	module joint() {
+		module joint_ring() {
+            hollow_out(ring_width)
+                circle(joint_ring_outer);
+		}
+
+		ring_height = height / 3 - spacing;
+        linear_extrude(ring_height) joint_ring();
+        translate([0, 0, height - ring_height]) 
+            linear_extrude(ring_height) joint_ring();
+			
+		translate([0, 0, half_h]) 
+			linear_extrude(height / 3, center = true) 
+				line2d([0, 0], [joint_r_outermost, 0], shaft_r * 2, p1Style = "CAP_BUTT", p2Style = "CAP_BUTT");
+		
+		// pillar
+		linear_extrude(height) circle(shaft_r);
+	}
+
+
+    offsetd = -spacing / 2;
+    tri_sq = triangle2square(tri_side_leng);
+    
+    module 2d_tri_square() {
+        difference() {
+            offset(offsetd) polygon(tri_sq[0][0]);
+            translate(tri_sq[1][2]) circle(joint_r_outermost);
+        }
+        difference() {
+            offset(offsetd) polygon(tri_sq[0][1]);
+            translate(tri_sq[1][0]) circle(joint_ring_inner);
+        }
+        
+        difference() {
+            offset(offsetd) polygon(tri_sq[0][2]);
+            translate(tri_sq[1][0]) circle(joint_r_outermost);
+            translate(tri_sq[1][1]) circle(joint_ring_inner);
+        }
+        
+        difference() {
+            offset(offsetd) polygon(tri_sq[0][3]);
+            translate(tri_sq[1][2]) circle(joint_ring_inner);
+            translate(tri_sq[1][1]) circle(joint_r_outermost);
+        }
+    }
+    
+    if(type == "CONTAINER") {
+        box_extrude(height = height, shell_thickness = ring_width) 
+            2d_tri_square();
+        
+        translate(tri_sq[1][0]) rotate(65) joint();
+        translate(tri_sq[1][1]) rotate(170) joint();
+        translate(tri_sq[1][2]) rotate(275) joint();    
+    }
+    else if(type == "COVER") {
+        box_extrude(height = ring_width * 2, shell_thickness = ring_width)  
+            mirror([1, 0, 0]) 
+                offset(-ring_width - spacing) 2d_tri_square();
+        linear_extrude(ring_width) mirror([1, 0, 0]) 2d_tri_square();
+    }
+}
+
+
+$fn = 36;
+triangle2square_box("CONTAINER", tri_side_leng, height, spacing, ring_width, shaft_r);
+triangle2square_box("COVER", tri_side_leng, height, spacing, ring_width, shaft_r);
+