Index: 3_hull.html
===================================================================
--- 3_hull.html	(revision 895)
+++ 3_hull.html	(revision 896)
@@ -177,7 +177,7 @@
 <p>
 
 <div class="img"><center>
-<p><img src="img/geo_wallin.png">
+<p><img src="img/geo_hwallin.png">
 <p>Figure 3/6. a. N1 inside N3, crossing edges; b. spokes and convex hull;
 c. path chosen; d. same case but no crossing; e. spokes and convex hull;
 f. path chosen;
@@ -191,10 +191,17 @@
 	<li> the other half is the resulting path; replace the offending line with this path
 </ul>
 
-TODO: zig-zag example: if the vertical dashed line is intersected from both
+<p>
+TODO: However, this will break in the following case:
+<div class="img"><center>
+<p><img src="img/geo_hwallin_brk.png">
+<p>Figure 3/x. zig-zag example: if the vertical dashed line is intersected from both
 left and right by N3, the hull won't work! probably go "one-by-one"?
+</center></div>
+<p>
 
 
+
 <h3> 3.4. Switch-layer cases: V1, V2, V3 </h3>
 <p>
 First exclude V1 or V2 depending on the existing objects on offending N1