added to these two gl-related files the system independent inclusion of GLU.

IT is necessary since the last version of QT does not include anymore glu when including QGL stuff

wrap/gl/glu_tesselator.h

@@ -29,6 +29,19 @@
 #error "Please include OpenGL before including this file"
 #endif
 
+
+// The inclusion of glu should be always safe (if someone has already included gl stuff).
+#ifndef GLU_VERSIONS
+#ifdef __APPLE__
+#include <OpenGL/glu.h>
+#else
+#ifdef _WIN32
+  #include <windows.h>
+#endif
+#include <GL/glu.h>
+#endif
+#endif
+
 #ifndef CALLBACK
 #ifdef _WIN32
 #define CALLBACK __stdcall

wrap/gl/picking.h

@@ -50,6 +50,18 @@ Revision 1.1  2005/12/03 09:36:28  ganovelli
 #define WRAP_GL_PICKING_H
 
 #include <algorithm>
+
+#ifndef GLU_VERSIONS
+#ifdef __APPLE__
+#include <OpenGL/glu.h>
+#else
+#ifdef _WIN32
+  #include <windows.h>
+#endif
+#include <GL/glu.h>
+#endif
+#endif
+
 namespace vcg
 {