14.2 Pointer Control

change-pointer-control

display &key :acceleration :threshold

Function

display: A display.
:acceleration: A number for the acceleration ratio.
:threshold: The number of pixels required for acceleration to take effect.

Changes the acceleration and/or the acceleration threshold of the pointer for the display. The :acceleration number is used as a multiplier, typically specified as a rational number of the form C/P, where C is the number of pixel positions of cursor motion displayed for P units of pointer device motion. The acceleration only occurs if the pointer moves more that :threshold pixels at once, and only applies to the motion beyond the :threshold . Either :acceleration or :threshold can be set to :default, that restores the default settings of the server.

pointer-control

display

Function

display: A display.

Returns the acceleration and threshold for the display pointer.

acceleration, threshold: Type number.

pointer-mapping

display &key ( :result-type 'list)

Function

display: A display.
:result-type: The type of sequence to return.

Returns or (with setf) changes the mapping of button numbers for the display pointer. The :result-type is not used when changing the mapping. If element i of the mapping sequence is j, then the events from pointer button j are reported by the server as events for button i+1. (Note that pointer buttons are numbered beginning with one, while the mapping sequence itself is indexed normally from zero.) If element i of the mapping sequence is zero, then button i+1 is disabled and can no longer generate input events. No two elements of the mapping can have the same non-zero value.

The length of the mapping sequence indicates the actual number of buttons on the device. When changing the mapping, the new mapping must have this same length.

mapping: Type sequence or card8.