+Spacing is calculated on triangulation edges. This implicitly assumes an edge
+is always a radial construct relative to the closest point (e.g. via). In
+the following example the almost vertical edge between cr 197 and cr 198, the
+starting from pin 1's south-east corner is going too close to pin 2. In
+the initial sketch it is not critical:
+
+
+
+But after the global puller, the route is identical to that edge:
+
+
+
+This route can not consider spacing to pin 2 because there is no near-perpendicular
+edge, radial from pin 2 against the route.
+
+Fix 1: It would be possible to insert such an edge, detecting a tangential
+edge is "too close" to pin 2. However adding such edges that are not radial
+from any obstacle may ruin trbs: the edge would be in the middle between pin
+rows and if there are enough vertical lines it is not clear where exactly it
+should be placed to not interfere with spacing.
+
+Fix 2: it would be possible to create an ocatagon for the triangulation at
+the round copper of the pin. But that wouldn't necessarily solve the
+problem because the tangential line would then be tangential to the corner
+of the octagon.
+
+
Index: fail1.svg
===================================================================
--- fail1.svg (nonexistent)
+++ fail1.svg (revision 796)
@@ -0,0 +1,265 @@
+
+
\ No newline at end of file
Index: fail2.svg
===================================================================
--- fail2.svg (nonexistent)
+++ fail2.svg (revision 796)
@@ -0,0 +1,265 @@
+
+
\ No newline at end of file
Index: trbs.html
===================================================================
--- trbs.html (revision 795)
+++ trbs.html (revision 796)
@@ -2,6 +2,10 @@
Triangulated Rubber Band Sketch
+
+Update: it turned out there is a case that TRBS
+can not handle so it can not be used for the toporouter.
+