add helix_lampshade

examples/helix_lampshade.scad

@@ -0,0 +1,96 @@
+use <hollow_out.scad>;
+
+model = "ALL"; // [JOIN, RING, ALL]
+radius = 131.3 / 2;
+width = 4;
+height = 2.5;
+layer_h = 12.5;
+layers = 21;
+
+module lamp_layer(radius, width, height) {
+    linear_extrude(height, center = true)
+    hollow_out(width)
+        circle(radius + width, $fn = 6);
+}
+
+module join(radius, width, height, layer_h, layer_hoff = 0.95) {
+    layer_a = 5;
+    difference() {
+        translate([radius - width / 2, 0, 0])
+        rotate(5) {
+            linear_extrude(height * 2, center = true)
+                square(width * 1.25 * 1.49, center = true);
+                
+            translate([-width * 1.25 * 1.49 / 4, width * .85, 0])
+            linear_extrude(layer_h)
+                square([width * 1.25 / 2 * 1.49, width * 1.5], center = true);
+                
+            translate([0, width * 1.6, layer_h])
+            linear_extrude(height * 2, center = true)
+                square(width * 1.25 * 1.49, center = true);
+        }
+        
+        for(i = [0:1]) {
+            translate([0, 0, layer_h * i])
+            rotate(layer_a * i)
+                 lamp_layer(r_circumscribed_circle, width, height * layer_hoff);
+        }
+    }
+}
+
+
+r_circumscribed_circle = radius / cos(30);
+
+if(model == "JOIN") {
+    color("white")
+    rotate(-5)
+    translate([-(r_circumscribed_circle - width / 2), 0, 0])
+    join(r_circumscribed_circle, width, height, layer_h);
+}
+else if(model == "RING") {
+    color("black")
+    lamp_layer(r_circumscribed_circle, width, height);
+}
+else {
+    layer_a = 5;    
+    n = layers - 1;
+
+    color("black") {
+        for(i = [0:2]) {
+            rotate(i * 120)
+                join(r_circumscribed_circle, width, height, layer_h);
+        }
+
+        translate([0, 0, layer_h])
+        rotate(65)
+        for(i = [0:2]) {
+            rotate(i * 120)
+                join(r_circumscribed_circle, width, height, layer_h);
+        }
+    }
+
+    color("white") 
+    for(h = [0:2:n - 2]) {
+        translate([0, 0, layer_h * (h)]) 
+        rotate((h) * 5) {
+            for(i = [0:2]) {
+                rotate(i * 120)
+                join(r_circumscribed_circle, width, height, layer_h);
+            }
+
+            translate([0, 0, layer_h])
+            rotate(65)
+            for(i = [0:2]) {
+                rotate(i * 120)
+                join(r_circumscribed_circle, width, height, layer_h);
+            }
+        }
+    }
+        
+    color("black")
+    for(i = [0:n]) {
+        translate([0, 0, layer_h * i])
+        rotate(layer_a * i)
+             lamp_layer(r_circumscribed_circle, width, height);
+    }
+}