'Think Different': enabled some demos to compile for OS X -i386

Demos/ConstraintDemo/ConstraintDemo.cpp

@@ -37,7 +37,14 @@ subject to the following restrictions:
 #ifdef WIN32 //needed for glut.h
 #include <windows.h>
 #endif
+//think different
+#if defined(__APPLE__) && !defined (VMDMESA)
+#include <OpenGL/gl.h>
+#include <OpenGL/glu.h>
+#include <GLUT/glut.h>
+#else
 #include <GL/glut.h>
+#endif
 #include "GL_ShapeDrawer.h"
 
 #include "GlutStuff.h"
@@ -386,4 +393,4 @@ void clientMouseFunc(int button, int state, int x, int y)
 }
 void	clientMotionFunc(int x,int y)
 {
-}
+}