Reorganize: kebab-case names, per-item subdirectories, regroup items

3d-honeycomb/honeycomb.scad

@@ -0,0 +1,73 @@
+// https://en.wikipedia.org/wiki/Bitruncated_cubic_honeycomb
+
+module _trunc_octa() {
+    octapoints = [
+        [+1, 0, 0],
+        [-1, 0, 0],
+        [0, +1, 0],
+        [0, -1, 0],
+        [0, 0, +1],
+        [0, 0, -1]
+    ];
+
+    octafaces = [
+        [4, 2, 0],
+        [4, 0, 3],
+        [4, 3, 1],
+        [4, 1, 2],
+        [5, 0, 2],
+        [5, 3, 0],
+        [5, 1, 3],
+        [5, 2, 1] 
+    ];
+
+    intersection() {
+        scale(3) {
+            polyhedron(points=octapoints, faces=octafaces);
+        }
+
+        cube(size=4, center=true);
+    }
+}
+
+module _hollow_trunc_octa(wall) {
+    difference() {
+        _trunc_octa();
+        
+        scale(1 - wall)
+        _trunc_octa();
+    }
+}
+
+module _3d_honeycomb(cells, wall) {
+    translate([2, 2, 2])
+    for (xi = [0 : cells[0] - 1]) {
+        translate([xi * 4, 0, 0])
+        for (yi = [0 : cells[1] - 1]) {
+            translate([0, yi * 4, 0])
+            for (zi = [0 : cells[2] - 1]) {
+                offset = (zi % 2 == 0) ? 0 : 2;
+                
+                translate([offset, offset, zi * 2])
+                _hollow_trunc_octa(wall=wall);
+            }
+        }
+    }
+}
+
+module 3d_honeycomb(dims, wall=0.2) {
+    intersection() {
+        translate([-2, -2, -2])
+        rotate([45, 0, 0])
+        _3d_honeycomb([
+            ceil(dims[0] / 4) + 1,
+            ceil(dims[1] / 4) + 1,
+            ceil(dims[2] / 2) + 1,
+        ],  wall=wall);
+        
+        cube(dims);
+    }
+}
+
+//scale(2)
+3d_honeycomb([16, 16, 16], wall=0.1);