glutKeyboardUpFunc  -  sets  the keyboard up (key release)
       callback for the current window.

SYNTAX

       void glutKeyboardUpFunc(void (*func)(unsigned char key,
                             int x, int y));

ARGUMENTS

       func      The new keyboard up callback function.

DESCRIPTION

       glutKeyboardFunc sets the keyboard up (key release)  call-
       back  for  the current window.  When a user types into the
       window, each key release matching an ASCII character  will
       generate  a keyboard up callback. The key callback parame-
       ter is the generated ASCII character. The state  of  modi-
       fier  keys  such  as  Shift cannot be determined directly;
       their only effect will be on the returned ASCII data.  The
       x and y callback parameters indicate the mouse location in
       window relative coordinates when the key was pressed. When
       a new window is created, no keyboard callback is initially
       registered, and  ASCII  key  strokes  in  the  window  are
       ignored.  Passing  NULL  to  glutKeyboardFunc disables the
       generation of keyboard callbacks.

       During a keyboard up  callback,  glutGetModifiers  may  be
       called  to  determine  the state of modifier keys when the
       keystroke generating the callback occurred.

       To avoid the reporting of key release/press pairs  due  to
       auto   repeat,  use  glutIgnoreKeyRepeat  to  ignore  auto
       repeated keystrokes.

       There is no guarantee that  the  keyboard  press  callback
       will  match  the  exact ASCII character as the keyboard up
       callback.  For example, the key down may be for  a  lower-
       case  b,  but the key release may report an uppercase B if
       the shift state has changed.  The same applies to  symbols
       and  control  characters.   The precise behavior is window
       system dependent.

       Use glutSpecialUpFunc for a means to detect non-ASCII  key
       releases.

SEE ALSO

       glutKeyboardFunc, glutSpecialUpFunc, glutSpecialFunc,
       glutCreateWindow, glutMouseFunc,  glutSpaceballButtonFunc,
       glutButtonBoxFunc, glutTabletButtonFunc, glutGetModifiers,
       glutIgnoreKeyRepeat

AUTHOR

       Mark J. Kilgard (mjk@nvidia.com)