smoothed out the corners between catears and headband

scad/base/smoothing.scad

@@ -0,0 +1,18 @@
+//smoothing smooths a corner, spanned by v1, v2 and v3 with radius r
+module smoothing(v1, v2, v3, r, th = 0){
+  n1 = (v1-v2)/norm(v1-v2);
+  n2 = (v3-v2)/norm(v3-v2);
+  alpha = acos(n1*n2)/2;
+  n3 = (n1+n2)/norm(n1+n2);  
+    
+  centre = v2+n3*(r/sin(alpha));
+  l = r*sqrt((1/sin(alpha)^2)-1);
+
+  translate(th*n3){
+    difference(){
+      polygon([v2+l*n1,v2,v2+l*n2]);
+      translate(centre)
+        circle(r = r, $fn = 64);  
+    }
+  }  
+}