Bugfix: crash in some circumstances when avoid_crossing_perimeters is enabled. #2266

1 files changed, 13 insertions, 0 deletions

diff --git a/xs/src/libslic3r/MotionPlanner.cpp b/xs/src/libslic3r/MotionPlanner.cpp
index b562a2832..dd626cda7 100644
--- a/xs/src/libslic3r/MotionPlanner.cpp
+++ b/xs/src/libslic3r/MotionPlanner.cpp
@@ -18,10 +18,17 @@ MotionPlanner::~MotionPlanner()
         delete *graph;
 }
 
+size_t
+MotionPlanner::islands_count() const
+{
+    return this->islands.size();
+}
+
 void
 MotionPlanner::initialize()
 {
     if (this->initialized) return;
+    if (this->islands.empty()) return;  // prevent initialization of empty BoundingBox
     
     ExPolygons expp;
     for (ExPolygons::const_iterator island = this->islands.begin(); island != this->islands.end(); ++island) {
@@ -70,6 +77,12 @@ MotionPlanner::shortest_path(const Point &from, const Point &to, Polyline* polyl
 {
     if (!this->initialized) this->initialize();
     
+    if (this->islands.empty()) {
+        polyline->points.push_back(from);
+        polyline->points.push_back(to);
+        return;
+    }
+    
     // Are both points in the same island?
     int island_idx = -1;
     for (ExPolygons::const_iterator island = this->islands.begin(); island != this->islands.end(); ++island) {