glutDialsFunc(3GLUT) GLUT glutDialsFunc(3GLUT)

NAME
glutDialsFunc - sets the dial & button box dials callback
for the current window.

SYNTAX
void glutDialsFunc(void (*func)(int dial, int value));

ARGUMENTS
func The new dials callback function.

DESCRIPTION
glutDialsFunc sets the dial & button box dials callback
for the current window. The dial & button box dials call-
back for a window is called when the window has dial &
button box input focus (normally, when the mouse is in the
window) and the user generates dial & button box dial
changes. The dial parameter will be the dial number
(starting at one). The number of available dial & button
box dials can be determined with glutDe-
viceGet(GLUT_NUM_DIALS). The value measures the absolute
rotation in degrees. Dial values do not ‘‘roll over’’ with
each complete rotation but continue to accumulate degrees
(until the int dial value overflows).

Registering a dial & button box dials callback when a dial
& button box device is not available is ineffectual and
not an error. In this case, no dial & button box dials
callbacks will be generated.

Passing NULL to glutDialsFunc disables the generation of
dial & button box dials callbacks. When a new window is
created, no dial & button box dials callback is initially
registered.

SEE ALSO
glutButtonBoxFunc, glutDeviceGet

AUTHOR
Mark J. Kilgard (mjk@sgi.com)

GLUT 3.2 1