Pointer gestures

A global interface to provide semantic touchpad gestures for a given pointer.

Three gestures are currently supported: swipe, pinch, and hold. Pinch and swipe gestures follow a three-stage cycle: begin, update, end, hold gestures follow a two-stage cycle: begin and end. All gestures are identified by a unique id.

Warning! The protocol described in this file is experimental and backward incompatible changes may be made. Backward compatible changes may be added together with the corresponding interface version bump. Backward incompatible changes are done by bumping the version number in the protocol and interface names and resetting the interface version. Once the protocol is to be declared stable, the 'z' prefix and the version number in the protocol and interface names are removed and the interface version number is reset.

A swipe gesture object notifies a client about a multi-finger swipe gesture detected on an indirect input device such as a touchpad. The gesture is usually initiated by multiple fingers moving in the same direction but once initiated the direction may change. The precise conditions of when such a gesture is detected are implementation-dependent.

A gesture consists of three stages: begin, update (optional) and end. There cannot be multiple simultaneous hold, pinch or swipe gestures on a same pointer/seat, how compositors prevent these situations is implementation-dependent.

A gesture may be cancelled by the compositor or the hardware. Clients should not consider performing permanent or irreversible actions until the end of a gesture has been received.

A pinch gesture object notifies a client about a multi-finger pinch gesture detected on an indirect input device such as a touchpad. The gesture is usually initiated by multiple fingers moving towards each other or away from each other, or by two or more fingers rotating around a logical center of gravity. The precise conditions of when such a gesture is detected are implementation-dependent.

A gesture consists of three stages: begin, update (optional) and end. There cannot be multiple simultaneous hold, pinch or swipe gestures on a same pointer/seat, how compositors prevent these situations is implementation-dependent.

A gesture may be cancelled by the compositor or the hardware. Clients should not consider performing permanent or irreversible actions until the end of a gesture has been received.

A hold gesture object notifies a client about a single- or multi-finger hold gesture detected on an indirect input device such as a touchpad. The gesture is usually initiated by one or more fingers being held down without significant movement. The precise conditions of when such a gesture is detected are implementation-dependent.

In particular, this gesture may be used to cancel kinetic scrolling.

A hold gesture consists of two stages: begin and end. Unlike pinch and swipe there is no update stage. There cannot be multiple simultaneous hold, pinch or swipe gestures on a same pointer/seat, how compositors prevent these situations is implementation-dependent.

A gesture may be cancelled by the compositor or the hardware. Clients should not consider performing permanent or irreversible actions until the end of a gesture has been received.