Ported PrintObject::bounding_box() to XS

xs/src/libslic3r/PrintObject.cpp

@@ -111,6 +111,16 @@ PrintObject::reload_model_instances()
     return this->set_copies(copies);
 }
 
+void
+PrintObject::bounding_box(BoundingBox* bb) const
+{
+    // since the object is aligned to origin, bounding box coincides with size
+    Points pp;
+    pp.push_back(Point(0,0));
+    pp.push_back(this->size);
+    *bb = BoundingBox(pp);
+}
+
 void
 PrintObject::add_region_volume(int region_id, int volume_id)
 {