+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <simgear/compiler.h>
+
#include "trackball.h"
+#if defined(WIN32) || defined(__CYGWIN32__)
+#define WIN32_CURSOR_TWEAKS
+#elif (GLUT_API_VERSION >= 4 || GLUT_XLIB_IMPLEMENTATION >= 9)
+#define X_CURSOR_TWEAKS
+#endif
+
typedef enum {
MOUSE_POINTER,
MOUSE_YOKE,