diff --git a/scenenode.cpp b/scenenode.cpp
index ece55c66..88c93383 100644
--- a/scenenode.cpp
+++ b/scenenode.cpp
@@ -402,7 +402,7 @@ shape_node::merge( shape_node &Shape ) {
     m_data.area.center =
         interpolate(
             m_data.area.center, Shape.m_data.area.center,
-            static_cast<float>( Shape.m_data.vertices.size() ) / ( Shape.m_data.vertices.size() + m_data.vertices.size() ) );
+            static_cast<double>( Shape.m_data.vertices.size() ) / ( Shape.m_data.vertices.size() + m_data.vertices.size() ) );
     m_data.vertices.insert(
         std::end( m_data.vertices ),
         std::begin( Shape.m_data.vertices ), std::end( Shape.m_data.vertices ) );
@@ -622,7 +622,7 @@ lines_node::merge( lines_node &Lines ) {
     m_data.area.center =
         interpolate(
             m_data.area.center, Lines.m_data.area.center,
-            static_cast<float>( Lines.m_data.vertices.size() ) / ( Lines.m_data.vertices.size() + m_data.vertices.size() ) );
+            static_cast<double>( Lines.m_data.vertices.size() ) / ( Lines.m_data.vertices.size() + m_data.vertices.size() ) );
     m_data.vertices.insert(
         std::end( m_data.vertices ),
         std::begin( Lines.m_data.vertices ), std::end( Lines.m_data.vertices ) );
diff --git a/stdafx.h b/stdafx.h
index dadd3764..8fe77efa 100644
--- a/stdafx.h
+++ b/stdafx.h
@@ -3,7 +3,8 @@
 // are changed infrequently
 //
 
-#pragma once
+#ifndef STDAFX_H
+#define STDAFX_H
 
 #define _USE_MATH_DEFINES
 #include <cmath>
@@ -93,4 +94,4 @@
 #define STRINGIZE_DETAIL(x) #x
 #define STRINGIZE(x) STRINGIZE_DETAIL(x)
 #define glDebug(x) if (GLEW_GREMEDY_string_marker) glStringMarkerGREMEDY(0, __FILE__ ":" STRINGIZE(__LINE__) ": " x);
-
+#endif