kc3-lang/ftgl

diff --git a/src/FTBBox.cpp b/src/FTBBox.cpp
new file mode 100755
index 0000000..b6cde9f
--- /dev/null
+++ b/src/FTBBox.cpp
@@ -0,0 +1,18 @@
+#include "FTBBox.h"
+
+
+FTBBox operator + ( const FTBBox &a, const FTBBox &b) 
+{
+    FTBBox compositeBox;
+    
+    compositeBox.lowerX = a.lowerX < b.lowerX? a.lowerX: b.lowerX; 
+    compositeBox.lowerY = a.lowerY < b.lowerY? a.lowerY: b.lowerY;
+    compositeBox.lowerZ = a.lowerZ < b.lowerZ? a.lowerZ: b.lowerZ; 
+    compositeBox.upperX = a.upperX < b.upperX? a.upperX: b.upperX; 
+    compositeBox.upperY = a.upperY < b.upperY? a.upperY: b.upperY; 
+    compositeBox.upperZ = a.upperZ < b.upperZ? a.upperZ: b.upperZ; 
+    
+    
+    return compositeBox;
+}
+