NAME¶

XChangePointerControl, XGetPointerControl - control pointer

SYNTAX¶

int XChangePointerControl(Display *display, Bool do_accel, Bool do_threshold, int accel_numerator, int accel_denominator, int threshold);

int XGetPointerControl(Display *display, int *accel_numerator_return, int *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