cleanup generated thin wall polys

notes.md

@@ -2,7 +2,7 @@
 
 ## `C` cosmetic, `F` functional, `P` performance, `B` bug fix
 
-* `B` origin bug (Onshape?) when switching modes in 2.5 and 2.6
+* `B` origin (and bed size) bug (Onshape?) when switching modes in 2.5 and 2.6
 
 * `P` duplicate objects should share same slice data unless rotated or scaled
 * `P` allow selection to me decimated on demand (context menu?)

src/geo/polygon.js

@@ -444,6 +444,10 @@
                 for (let p of poly) {
                     np.push(p);
                 }
+                np = np.clean();
+                if (np.last().distTo2D(np.first()) <= max) {
+                    np.push(np.first());
+                }
                 return np;
             });
     };