X Version 11 (1 September 1988) XChangePointerControl(XS)
NAME
XChangePointerControl, XGetPointerControl - control pointer
SYNTAX
XChangePointerControl(display, do_accel, do_threshold,
accel_numerator,
accel_denominator, threshold)
Display *display;
Bool do_accel, do_threshold;
int accel_numerator, accel_denominator;
int threshold;
XGetPointerControl(display, accel_numerator_return,
accel_denominator_return,
threshold_return)
Display *display;
int *accel_numerator_return,
*accel_denominator_return;
int *threshold_return;
ARGUMENTS
accel_denominator
Specifies the denominator for the acceleration
multiplier.
accel_denominator_return
Returns the denominator for the acceleration
multiplier.
accel_numerator
Specifies the numerator for the acceleration
multiplier.
accel_numerator_return
Returns the numerator for the acceleration
multiplier.
display Specifies the connection to the X server.
do_accel Specifies a Boolean value that controls whether
the values for the accel_numerator or
accel_denominator are used.
do_threshold
Specifies a Boolean value that controls whether
the value for the threshold is used.
threshold Specifies the acceleration threshold.
threshold_return
Returns the acceleration threshold.
DESCRIPTION
The XChangePointerControl function defines how the pointing
device moves. The acceleration, expressed as a fraction, is
a multiplier for movement. For example, specifying 3/1 means
the pointer moves three times as fast as normal. The
fraction may be rounded arbitrarily by the X server.
Acceleration only takes effect if the pointer moves more
than threshold pixels at once and only applies to the amount
beyond the value in the threshold argument. Setting a value
to -1 restores the default. The values of the do_accel and
do_threshold arguments must be True for the pointer values
to be set, or the parameters are unchanged. Negative values
(other than -1) generate a BadValue error, as does a zero
value for the accel_denominator argument.
XChangePointerControl can generate a BadValue error.
The XGetPointerControl function returns the pointer's
current acceleration multiplier and acceleration threshold.
DIAGNOSTICS
BadValue Some numeric value falls outside the range of
values accepted by the request. Unless a specific
range is specified for an argument, the full range
defined by the argument's type is accepted. Any
argument defined as a set of alternatives can
generate this error.
SEE ALSO
Xlib - C Language X Interface
(printed 2/12/90) (1 September 1988)ChangePointerControl(XS)