From 74b95e91522cc7cbdea8d83d42ed424d0a9ed20c Mon Sep 17 00:00:00 2001
From: bubnikv <bubnikv@gmail.com>
Date: Wed, 5 Apr 2017 09:52:06 +0200
Subject: [PATCH] Adapted BoundingBox get_extents(const ExPolygons &expolygons)
 to work even with empty polygons.

---
 xs/src/libslic3r/ExPolygon.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/xs/src/libslic3r/ExPolygon.cpp b/xs/src/libslic3r/ExPolygon.cpp
index e97c82532..1d4bac50b 100644
--- a/xs/src/libslic3r/ExPolygon.cpp
+++ b/xs/src/libslic3r/ExPolygon.cpp
@@ -553,9 +553,9 @@ BoundingBox get_extents(const ExPolygons &expolygons)
 {
     BoundingBox bbox;
     if (! expolygons.empty()) {
-        bbox = get_extents(expolygons.front());
-        for (size_t i = 1; i < expolygons.size(); ++ i)
-            bbox.merge(get_extents(expolygons[i]));
+        for (size_t i = 0; i < expolygons.size(); ++ i)
+			if (! expolygons[i].contour.points.empty())
+				bbox.merge(get_extents(expolygons[i]));
     }
     return bbox;
 }