glutJoystickFunc - sets the joystick callback for the cur-
       rent window.

SYNTAX

       void glutJoystickFunc(void (*func)(unsigned int buttonMask,
                            int x, int y, int z), int pollInterval);

ARGUMENTS

       func      The new joystick callback function.

       pollInterval
                 Joystick polling interval in milliseconds.

DESCRIPTION

       glutJoystickFunc sets the joystick callback for  the  cur-
       rent window.

       The  joystick  callback is called either due to polling of
       the joystick at the uniform timer  interval  specified  by
       pollInterval  (in  milliseconds) or in response to calling
       glutForceJoystickFunc.  If the pollInterval  is  non-posi-
       tive, no joystick polling is performed and the GLUT appli-
       cation must frequently (usually  from  an  idle  callback)
       call glutForceJoystickFunc.

       The  joystick  buttons are reported by the callback's but-
       tonMask parameter.  The  constants  GLUT_JOYSTICK_BUTTON_A
       (0x1),  GLUT_JOYSTICK_BUTTON_B  (0x2),  GLUT_JOYSTICK_BUT-
       TON_C (0x4), and GLUT_JOYSTICK_BUTTON_D (0x8) are provided
       for programming convience.

       The x, y, and z callback parameters report the X, Y, and Z
       axes  of  the  joystick.   The  joystick  is  centered  at
       (0,0,0).   X,  Y,  and Z are scaled to range between -1000
       and 1000.  Moving the joystick left  reports  negative  X;
       right  reports  positive X.  Pulling the stick towards you
       reports negative Y; push the stick away from  you  reports
       positive  Y.   If the joystick has a third axis (rudder or
       up/down), down reports negative Z; up reports positive  Z.

       Passing  a NULL func to glutJoystickFunc disables the gen-
       eration of joystick callbacks.  Without a  joystick  call-
       back registered, glutForceJoystickFunc does nothing.

       When a new window is created, no joystick callback is ini-
       tially registered.

LIMITATIONS

       The GLUT joystick callback only reports the first  3  axes
       and 32 buttons.  GLUT supports only a single joystick.

GLUT IMPLEMENTATION NOTES FOR X11

       tation of GLUT for X11 may add joystick support.

GLUT IMPLEMENTATION NOTES FOR WIN32

       The GLUT 3.7 implementation of GLUT for Win32 supports the
       joystick API and joystick input, but does so  through  the
       dated  joySetCapture and joyGetPosEx Win32 Multimedia API.
       The GLUT 3.7 joystick support for Win32 has all the  limi-
       tations  of  the Win32 Multimedia API joystick support.  A
       future implementation of GLUT for Win32 may use  DirectIn-
       put.

SEE ALSO

       glutForceJoystickFunc, glutMotionFunc, glutMouseFunc,
       glutSpaceballButtonFunc, glutSpaceballMotionFunc, glutButtonBoxFunc,
       glutTabletButtonFunc, glutDeviceGet

AUTHOR

       Mark J. Kilgard (mjk@nvidia.com)