Revision control
++ <?xml version="1.0" encoding="UTF-8"?>
++ <protocol name="pointer_gestures_unstable_v1">
++
++ <interface name="zwp_pointer_gestures_v1" version="2">
++ <description summary="touchpad gestures">
++ A global interface to provide semantic touchpad gestures for a given
++ pointer.
++
++ Two gestures are currently supported: swipe and zoom/rotate.
++ All gestures follow a three-stage cycle: begin, update, end and
++ 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.
++ </description>
++
++ <request name="get_swipe_gesture">
++ <description summary="get swipe gesture">
++ Create a swipe gesture object. See the
++ wl_pointer_gesture_swipe interface for details.
++ </description>
++ <arg name="id" type="new_id" interface="zwp_pointer_gesture_swipe_v1"/>
++ <arg name="pointer" type="object" interface="wl_pointer"/>
++ </request>
++
++ <request name="get_pinch_gesture">
++ <description summary="get pinch gesture">
++ Create a pinch gesture object. See the
++ wl_pointer_gesture_pinch interface for details.
++ </description>
++ <arg name="id" type="new_id" interface="zwp_pointer_gesture_pinch_v1"/>
++ <arg name="pointer" type="object" interface="wl_pointer"/>
++ </request>
++
++ <!-- Version 2 additions -->
++
++ <request name="release" type="destructor" since="2">
++ <description summary="destroy the pointer gesture object">
++ Destroy the pointer gesture object. Swipe and pinch objects created via this
++ gesture object remain valid.
++ </description>
++ </request>
++ </interface>
++
++ <interface name="zwp_pointer_gesture_swipe_v1" version="2">
++ <description summary="a swipe gesture object">
++ 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 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.
++ </description>
++
++ <request name="destroy" type="destructor">
++ <description summary="destroy the pointer swipe gesture object"/>
++ </request>
++
++ <event name="begin">
++ <description summary="multi-finger swipe begin">
++ This event is sent when a multi-finger swipe gesture is detected
++ on the device.
++ </description>
++ <arg name="serial" type="uint"/>
++ <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
++ <arg name="surface" type="object" interface="wl_surface"/>
++ <arg name="fingers" type="uint" summary="number of fingers"/>
++ </event>
++
++ <event name="update">
++ <description summary="multi-finger swipe motion">
++ This event is sent when a multi-finger swipe gesture changes the
++ position of the logical center.
++
++ The dx and dy coordinates are relative coordinates of the logical
++ center of the gesture compared to the previous event.
++ </description>
++ <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
++ <arg name="dx" type="fixed" summary="delta x coordinate in surface coordinate space"/>
++ <arg name="dy" type="fixed" summary="delta y coordinate in surface coordinate space"/>
++ </event>
++
++ <event name="end">
++ <description summary="multi-finger swipe end">
++ This event is sent when a multi-finger swipe gesture ceases to
++ be valid. This may happen when one or more fingers are lifted or
++ the gesture is cancelled.
++
++ When a gesture is cancelled, the client should undo state changes
++ caused by this gesture. What causes a gesture to be cancelled is
++ implementation-dependent.
++ </description>
++ <arg name="serial" type="uint"/>
++ <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
++ <arg name="cancelled" type="int" summary="1 if the gesture was cancelled, 0 otherwise"/>
++ </event>
++ </interface>
++
++ <interface name="zwp_pointer_gesture_pinch_v1" version="2">
++ <description summary="a pinch gesture object">
++ 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 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.
++ </description>
++
++ <request name="destroy" type="destructor">
++ <description summary="destroy the pinch gesture object"/>
++ </request>
++
++ <event name="begin">
++ <description summary="multi-finger pinch begin">
++ This event is sent when a multi-finger pinch gesture is detected
++ on the device.
++ </description>
++ <arg name="serial" type="uint"/>
++ <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
++ <arg name="surface" type="object" interface="wl_surface"/>
++ <arg name="fingers" type="uint" summary="number of fingers"/>
++ </event>
++
++ <event name="update">
++ <description summary="multi-finger pinch motion">
++ This event is sent when a multi-finger pinch gesture changes the
++ position of the logical center, the rotation or the relative scale.
++
++ The dx and dy coordinates are relative coordinates in the
++ surface coordinate space of the logical center of the gesture.
++
++ The scale factor is an absolute scale compared to the
++ pointer_gesture_pinch.begin event, e.g. a scale of 2 means the fingers
++ are now twice as far apart as on pointer_gesture_pinch.begin.
++
++ The rotation is the relative angle in degrees clockwise compared to the previous
++ pointer_gesture_pinch.begin or pointer_gesture_pinch.update event.
++ </description>
++ <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
++ <arg name="dx" type="fixed" summary="delta x coordinate in surface coordinate space"/>
++ <arg name="dy" type="fixed" summary="delta y coordinate in surface coordinate space"/>
++ <arg name="scale" type="fixed" summary="scale relative to the initial finger position"/>
++ <arg name="rotation" type="fixed" summary="angle in degrees cw relative to the previous event"/>
++ </event>
++
++ <event name="end">
++ <description summary="multi-finger pinch end">
++ This event is sent when a multi-finger pinch gesture ceases to
++ be valid. This may happen when one or more fingers are lifted or
++ the gesture is cancelled.
++
++ When a gesture is cancelled, the client should undo state changes
++ caused by this gesture. What causes a gesture to be cancelled is
++ implementation-dependent.
++ </description>
++ <arg name="serial" type="uint"/>
++ <arg name="time" type="uint" summary="timestamp with millisecond granularity"/>
++ <arg name="cancelled" type="int" summary="1 if the gesture was cancelled, 0 otherwise"/>
++ </event>
++ </interface>
++
++ </protocol>