diff --git a/src/slic3r/GUI/CalibrationBedDialog.cpp b/src/slic3r/GUI/CalibrationBedDialog.cpp
index 1844af154..a3b7e54fe 100644
--- a/src/slic3r/GUI/CalibrationBedDialog.cpp
+++ b/src/slic3r/GUI/CalibrationBedDialog.cpp
@@ -7,7 +7,6 @@
 #include <wx/scrolwin.h>
 #include <wx/display.h>
 #include <wx/file.h>
-#include <cmath>
 #include "wxExtensions.hpp"
 
 #if ENABLE_SCROLLABLE
@@ -121,8 +120,8 @@ void CalibrationBedDialog::create_geometry(wxCommandEvent& event_args) {
     float offsetx = 10 + 10 * xyScale;
     float offsety = 10 + 10 * xyScale;
     if (bed_shape->values.size() > 4) {
-        offsetx = bed_size.x() / 2 - bed_size.x() * std::sqrtf(2) / 4 + 10 * xyScale;
-        offsety = bed_size.y() / 2 - bed_size.y() * std::sqrtf(2) / 4 + 10 * xyScale;
+        offsetx = bed_size.x() / 2 - bed_size.x() * 1.414 / 4 + 10 * xyScale;
+        offsety = bed_size.y() / 2 - bed_size.y() * 1.414 / 4 + 10 * xyScale;
     }
     bool large_enough = bed_shape->values.size() == 4 ?
         (bed_size.x() > offsetx * 3 && bed_size.y() > offsety * 3) :
diff --git a/src/slic3r/GUI/CalibrationBridgeDialog.cpp b/src/slic3r/GUI/CalibrationBridgeDialog.cpp
index 5c0251889..ad195a700 100644
--- a/src/slic3r/GUI/CalibrationBridgeDialog.cpp
+++ b/src/slic3r/GUI/CalibrationBridgeDialog.cpp
@@ -2,7 +2,7 @@
 #include "I18N.hpp"
 #include "libslic3r/Utils.hpp"
 #include "GUI.hpp"
-#include "tab.hpp"
+#include "Tab.hpp"
 #include <wx/scrolwin.h>
 #include <wx/display.h>
 #include <wx/file.h>
@@ -105,8 +105,8 @@ void CalibrationBridgeDialog::create_geometry(wxCommandEvent& event_args) {
     float offsetx = 10 + 10 * xyScale;
     float offsety = 10 + 10 * xyScale;
     if (bed_shape->values.size() > 4) {
-        offsetx = bed_size.x() / 2 - bed_size.x() * std::sqrtf(2) / 4 + 10 * xyScale;
-        offsety = bed_size.y() / 2 - bed_size.y() * std::sqrtf(2) / 4 + 10 * xyScale;
+        offsetx = bed_size.x() / 2 - bed_size.x() * 1.412 / 4 + 10 * xyScale;
+        offsety = bed_size.y() / 2 - bed_size.y() * 1.412 / 4 + 10 * xyScale;
     }
     bool large_enough = bed_shape->values.size() == 4 ?
         (bed_size.x() > offsetx * 3 && bed_size.y() > offsety * 3) :
diff --git a/src/slic3r/GUI/CalibrationFlowDialog.cpp b/src/slic3r/GUI/CalibrationFlowDialog.cpp
index 771546859..471a5a70a 100644
--- a/src/slic3r/GUI/CalibrationFlowDialog.cpp
+++ b/src/slic3r/GUI/CalibrationFlowDialog.cpp
@@ -1,7 +1,6 @@
 #include "CalibrationFlowDialog.hpp"
 #include "I18N.hpp"
 #include "libslic3r/Utils.hpp"
-#include "GLCanvas3D.hpp "
 #include "GUI.hpp"
 #include "GUI_ObjectList.hpp"
 #include "Tab.hpp"
diff --git a/src/slic3r/GUI/CalibrationTempDialog.cpp b/src/slic3r/GUI/CalibrationTempDialog.cpp
index a8047ffaf..5ff28519d 100644
--- a/src/slic3r/GUI/CalibrationTempDialog.cpp
+++ b/src/slic3r/GUI/CalibrationTempDialog.cpp
@@ -1,7 +1,6 @@
 #include "CalibrationTempDialog.hpp"
 #include "I18N.hpp"
 #include "libslic3r/Utils.hpp"
-#include "GLCanvas3D.hpp "
 #include "GUI.hpp"
 #include "GUI_ObjectList.hpp"
 #include "Tab.hpp"