fix thin lines and fill offset. fix noodle render and z layer moves

src/geo/polygons.js

@@ -528,6 +528,7 @@
             opt.gaps.push(suba);
         }
 
+        // if offset fails, consider last polygons as gap areas
         if (opt.gaps && !polys.length) {
             opt.gaps.push(orig);
         }
@@ -547,11 +548,6 @@
             }
         }
 
-        // if the polys fail to offset at the top level, consider them gaps
-        if (opt.gaps && polys.length === 0 && depth === 0) {
-            opt.gaps.push(orig);
-        }
-
         return polys;
     }