From da43cd70b20c4ad8ac5e1b6800e6ab3dfd371179 Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Tue, 1 May 2012 15:23:17 +0200
Subject: [PATCH] Prevent tiny extrusion points. #323

---
 lib/Slic3r/Layer.pm | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/lib/Slic3r/Layer.pm b/lib/Slic3r/Layer.pm
index efeea2093..370964f41 100644
--- a/lib/Slic3r/Layer.pm
+++ b/lib/Slic3r/Layer.pm
@@ -142,14 +142,17 @@ sub make_surfaces {
             1,
         );
         
-        # TODO: remove very small expolygons from diff before attempting to do medial axis
-        # (benchmark first)
-        push @{$self->thin_walls},
-            grep $_,
-            map $_->medial_axis(scale $Slic3r::flow_width),
-            @$diff;
-        
-        Slic3r::debugf "  %d thin walls detected\n", scalar(@{$self->thin_walls}) if @{$self->thin_walls};
+        if (@$diff) {
+            my $area_threshold = scale($Slic3r::flow_spacing) ** 2;
+            @$diff = grep $_->area > ($area_threshold), @$diff;
+            
+            push @{$self->thin_walls},
+                grep $_,
+                map $_->medial_axis(scale $Slic3r::flow_width),
+                @$diff;
+            
+            Slic3r::debugf "  %d thin walls detected\n", scalar(@{$self->thin_walls}) if @{$self->thin_walls};
+        }
     }
     
     if (0) {