diff --git a/src/libslic3r/Feature/FuzzySkin/FuzzySkin.cpp b/src/libslic3r/Feature/FuzzySkin/FuzzySkin.cpp
index 66fc90dc99..2e6f7efd9d 100644
--- a/src/libslic3r/Feature/FuzzySkin/FuzzySkin.cpp
+++ b/src/libslic3r/Feature/FuzzySkin/FuzzySkin.cpp
@@ -3,6 +3,7 @@
 #include "libslic3r/Algorithm/LineSplit.hpp"
 #include "libslic3r/Arachne/utils/ExtrusionJunction.hpp"
 #include "libslic3r/Arachne/utils/ExtrusionLine.hpp"
+#include "libslic3r/ClipperUtils.hpp"
 #include "libslic3r/Layer.hpp"
 #include "libslic3r/PerimeterGenerator.hpp"
 #include "libslic3r/Point.hpp"
diff --git a/src/libslic3r/Feature/Interlocking/InterlockingGenerator.cpp b/src/libslic3r/Feature/Interlocking/InterlockingGenerator.cpp
index df337f0193..a3e6cd21b0 100644
--- a/src/libslic3r/Feature/Interlocking/InterlockingGenerator.cpp
+++ b/src/libslic3r/Feature/Interlocking/InterlockingGenerator.cpp
@@ -2,6 +2,7 @@
 // CuraEngine is released under the terms of the AGPLv3 or higher.
 
 #include "InterlockingGenerator.hpp"
+#include "libslic3r/ClipperUtils.hpp"
 #include "Layer.hpp"
 
 namespace std {
diff --git a/src/libslic3r/Format/svg.cpp b/src/libslic3r/Format/svg.cpp
index 4a96274b99..7bfd73b987 100644
--- a/src/libslic3r/Format/svg.cpp
+++ b/src/libslic3r/Format/svg.cpp
@@ -1,3 +1,4 @@
+#include "libslic3r/ClipperUtils.hpp"
 #include "../libslic3r.h"
 #include "../Model.hpp"
 #include "../TriangleMesh.hpp"
@@ -19,9 +20,8 @@
 #include "TopExp_Explorer.hxx"
 #include "TopoDS.hxx"
 #include "BRepExtrema_SelfIntersection.hxx"
-#include "clipper/clipper.hpp"
-
-using namespace ClipperLib;
+#include "libslic3r/clipper.hpp"
+#include "libslic3r/Polygon.hpp"
 
 namespace Slic3r {
 const double STEP_TRANS_CHORD_ERROR = 0.005;
@@ -213,9 +213,9 @@ bool get_svg_profile(const char *path, std::vector<Element_Info> &element_infos,
             for (int i = 0; i < path_line_points.size(); ++i) {
                 ClipperLib::Path pt_path;
                 for (auto line_point : path_line_points[i]) { 
-                    pt_path.push_back(IntPoint(line_point.first.X() * scale_size, line_point.first.Y() * scale_size));
+                    pt_path.push_back(ClipperLib::IntPoint(line_point.first.X() * scale_size, line_point.first.Y() * scale_size));
                 }
-                pt_path.push_back(IntPoint(path_line_points[i].back().second.X() * scale_size, path_line_points[i].back().second.Y() * scale_size));
+                pt_path.push_back(ClipperLib::IntPoint(path_line_points[i].back().second.X() * scale_size, path_line_points[i].back().second.Y() * scale_size));
 
                 ClipperLib::Paths         out_paths;
                 ClipperLib::ClipperOffset co;
diff --git a/src/libslic3r/GCode/GCodeProcessor.cpp b/src/libslic3r/GCode/GCodeProcessor.cpp
index 7883e1ae30..6de15d8477 100644
--- a/src/libslic3r/GCode/GCodeProcessor.cpp
+++ b/src/libslic3r/GCode/GCodeProcessor.cpp
@@ -4,6 +4,7 @@
 #include "libslic3r/libslic3r.h"
 #include "libslic3r/Utils.hpp"
 #include "libslic3r/Print.hpp"
+#include "libslic3r/ClipperUtils.hpp"
 #include "libslic3r/LocalesUtils.hpp"
 #include "libslic3r/format.hpp"
 #include "GCodeProcessor.hpp"
diff --git a/src/libslic3r/GCode/TimelapsePosPicker.cpp b/src/libslic3r/GCode/TimelapsePosPicker.cpp
index 5ffd78b39b..cea7e8a45c 100644
--- a/src/libslic3r/GCode/TimelapsePosPicker.cpp
+++ b/src/libslic3r/GCode/TimelapsePosPicker.cpp
@@ -1,3 +1,4 @@
+#include "ClipperUtils.hpp"
 #include "TimelapsePosPicker.hpp"
 #include "Layer.hpp"
 
diff --git a/src/libslic3r/Model.cpp b/src/libslic3r/Model.cpp
index 71fa7cc2fb..d2878c5a32 100644
--- a/src/libslic3r/Model.cpp
+++ b/src/libslic3r/Model.cpp
@@ -1,6 +1,7 @@
 #include "Model.hpp"
 #include "libslic3r.h"
 #include "BuildVolume.hpp"
+#include "ClipperUtils.hpp"
 #include "Exception.hpp"
 #include "Model.hpp"
 #include "ModelArrange.hpp"
diff --git a/src/libslic3r/calib.hpp b/src/libslic3r/calib.hpp
index a887d17478..445162ded0 100644
--- a/src/libslic3r/calib.hpp
+++ b/src/libslic3r/calib.hpp
@@ -11,6 +11,7 @@ namespace Slic3r {
 
 class GCode;
 class Model;
+class ModelObject;
 
 enum class CalibMode : int {
     Calib_None = 0,
diff --git a/src/slic3r/GUI/BedShapeDialog.cpp b/src/slic3r/GUI/BedShapeDialog.cpp
index 5c7cc94771..ff2697558b 100644
--- a/src/slic3r/GUI/BedShapeDialog.cpp
+++ b/src/slic3r/GUI/BedShapeDialog.cpp
@@ -11,6 +11,7 @@
 #include "libslic3r/BoundingBox.hpp"
 #include "libslic3r/Model.hpp"
 #include "libslic3r/Polygon.hpp"
+#include "libslic3r/ClipperUtils.hpp"
 
 #include "Widgets/LabeledStaticBox.hpp"
 #include "Widgets/DialogButtons.hpp"
diff --git a/src/slic3r/Utils/CalibUtils.cpp b/src/slic3r/Utils/CalibUtils.cpp
index 44ff29ea87..075484891a 100644
--- a/src/slic3r/Utils/CalibUtils.cpp
+++ b/src/slic3r/Utils/CalibUtils.cpp
@@ -5,6 +5,7 @@
 #include "../GUI/Jobs/ProgressIndicator.hpp"
 #include "../GUI/PartPlate.hpp"
 #include "libslic3r/CutUtils.hpp"
+#include "libslic3r/ClipperUtils.hpp"
 
 #include "libslic3r/Model.hpp"
 #include "slic3r/GUI/Jobs/BoostThreadWorker.hpp"