Add a simple class definition here that was removed from SimGear.

src/Lib/Polygon/point2d.hxx

@@ -0,0 +1,19 @@
+/**
+ * Simple 2d point class where members can be accessed as x, dist, or lon
+ * and y, theta, or lat
+ */
+
+class point2d {
+public:
+    union {
+        double x;
+        double dist;
+        double lon;
+    };
+    union {
+        double y;
+        double theta;
+        double lat;
+    };
+};
+

src/Lib/Polygon/polygon.cxx

@@ -41,6 +41,7 @@ SG_USING_STD(endl);
 #include <poly2tri/interface.h>
 
 #include "polygon.hxx"
+#include "point2d.hxx"
 
 // Constructor 
 TGPolygon::TGPolygon( void )