path: root/XI2proto.txt

                The X Input Extension
                   Version 2.0

                   Peter Hutterer
               peter.hutterer@redhat.com
                    Red Hat, Inc.



1. Introduction

The X Input Extension version 2.0 (XI2) is the second major release of the X
Input Extension.

FIXME
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2. Notations used in this document

Notation for requests:
┌───
    Name of request
        name of request field:       type of request field
        name of request field:       type of request field
        ▶
        name of reply field:         type of reply field
└───

Notation for events:
┌───
    Name of event
        name of field:               type of field
        name of field:               type of field
└───

Complex fields are specified in the following notation:
          name of field:                  COMPLEXFIELDTYPE
or, if multiple of these fields exist:
          name of field:                  LISTofCOMPLEXFIELDTYPE

COMPLEXFIELDTYPE:  { name of subfield:   type of subfield,
                    name of subfield:   type of subfield }

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3. Interoperability between version 1.x and 2.0

FIXME

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4. The Master/Slave device hierarchy

XI2 introduces a device hierarchy split up into so-called Master Devices (MD)
and Slave Devices (SD).

4.1 Master devices
An MD is a virtual device created and managed by the server. MDs may send core
events and XI events. However, an MD does not represent a physical device and
relies on SDs for event generation. MDs come in two forms: as master pointers
or as master keyboards. A master pointer is represented by a visible cursor on
the screen. A master keyboard is represented by a keyboard focus.

Each master pointer is paired with the respective master keyboard and vice
versa, and this pairing is constant for the lifetime of both input devices.
Clients can use this pairing behaviour to implement input paradigms that
require pointer and keyboard interation (e.g. SHIFT + Click).

4.2 Slave devices
An SD is usually a physical device configured in the server. SDs are not
represented by a cursor or keyboard focus and may be attached to a master
pointer or master keyboard. SDs can only be attached to any master of the same
type (e.g. a physical pointer device can be attached to any master pointer).

If an event is generated by an SD
- if the SD is attached to a master pointer, it changes the position and/or
  button state of the master pointer.
- if the SD is attached to a master keyboard, it sends events to this
  keyboard's focus window (if applicable) and/or changes the modifier state of
  this keyboard.
- if the SD is not attached to an SD ("floating"), it does not change the
  any master device. The SD has its own (invisible) sprite and its own focus.
  Both the sprite and the focus must be managed explicitly by the client
  program.

4.3 Event processing for attached slave devices

Whenever an SD changes its logical state,
- the event is delivered as an XI event to any interested clients. If the
  device is floating, event processing stops.
  Otherwise, if the device is attached,
- the master device changes its classes to reflect the SD's capabilities. All
  interested clients are notified of this device change.
- then, the event is delivered as an XI event from the MD to any interested
  clients. If the event has been delivered, event processing stops.
  Otherwise,
- the event is delivered as a core event to any interested clients.

Given that W is the event window, and P the parent window of W, event delivery
to P is only attempted if neither the XI event, nor the core event has been
delivered on W. Once an event has been delivered as either XI or core event,
event processing stops.

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5. Data types

BUTTONMASK
        A binary mask defined as (1 << button number).
        A SETofBUTTONMASK is a binary OR of zero or more BUTTONMASK.

DEVICE { DEVICEID, AllDevices, AllMasterDevices }
        A DEVICE specifies either a DEVICEID or AllDevices or
        AllMasterDevices.

DEVICEID { CARD16 }
        A DEVICEID is a numerical ID for a device currently available in the
        server. The server may re-use a device ID after a device's removal.
        The device IDs 0 and 1 are reserved.
        AllDevices ........ 0
        AllMasterDevices .. 1

DEVICEUSE { MasterPointer, MasterKeyboard, SlavePointer,
            SlaveKeyboard, FloatingSlave }
        A DEVICEUSE field specifies the current use of a device in the MD/SD
        device hierarchy. See Section 4 for more information.

EVENTMASK
        An EVENTMASK is a binary mask defined as (1 << event type).
        A SETofEVENTMASK is a binary OR of zero or more EVENTMASK.

FP1616
        Fixed point decimal in 16.16 format as 32 bit integer in the form of
        (value * 10e15). The client is required to convert to 16.16 decimal
        format.

FP3232
        Fixed point decimal in 32.32 format as one INT32 and one CARD32.
        The INT32 contains the integral part, the CARD32 the decimal fraction
        shifted by 32.

VALUATORMASK
        A binary mask defined as (1 << valuator number).
        A SETofVALUATORMASK is a binary OR of zero or more VALUATORMASK.

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6. Errors

Errors are sent using core X error reports.

Device
        A value for a DEVICE argument does not specify a valid DEVICE.

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7. Requests:

The server does not guarantee that the length of a reply remains constant in
future revisions of XI2. A client must always retrieve the exact length of the
protocol reply from the connection, even if the reply is longer than defined
for the XI2 version supported by the client.
Additional bytes in a request may include data supported in later versions of
XI2. Clients should ignore this data.

7.1 Requests introduced in version 2.0

    ┌───
        XIQueryVersion
        major_version:          CARD16
        minor_version:          CARD16
        ▶
        major_version:          CARD16
        minor_version:          CARD16
    └───

    The client sends the highest supported version to the server and the
    server sends the highest version it supports, but no higher than the
    requested version. Major versions changes can introduce incompatibilities
    in existing functionality, minor version changes introduce only backward
    compatible changes.  It is the clients responsibility to ensure that the
    server supports a version which is compatible with its expectations.

    major_version
        Major XI2 version.
    minor_version
        Minor XI2 version.

    ┌───
        XIQueryDevice
        DEVICE                  deviceid
        ▶
        num_devices:            CARD16
        deviceinfo:             LISTofDEVICEINFO
    └───

    DEVICEINFO { deviceid:              DEVICEID
                 use:                   DEVICEUSE
                 attachment:            DEVICEID
                 enabled:               BOOL
                 num_classes:           CARD16
                 name_len:              CARD16
                 name:                  LISTofCHAR8
                 classes:               LISTofCLASS }

    CLASS { BUTTONCLASS KEYCLASS, AXISCLASS }

    BUTTONCLASS { type:                 ButtonClass
                  length:               CARD16
                  num_buttons:          CARD16
                  buttons:              LISTofATOM }

    KEYCLASS    { type:                 KeyClass
                  length:               CARD16
                  num_keys:             CARD16
                  keys:                 LISTofCARD32 }

    AXISCLASS   { type:                 AxisClass
                  length:               CARD16
                  axisnumber:           CARD16
                  axisname:             ATOM
                  min:                  FP3232
                  max:                  FP3232
                  resolution:           CARD32 }

    XIQueryDevices details information about the requested input devices.

    devices
        The device to list. If 'devices' is AllDevices, all enabled and
        disabled devices are listed. If 'devices' is AllMasterDevices, all
        enabled and disabled master devices are listed. If 'devices' is a
        valid DEVICE, only this DEVICE is listed and 'num_devices' is 1.
    num_devices
        The number of 'deviceinfos' returned.

    Each 'deviceinfo' is detailed as follows:
    deviceid
        The unique ID of the device. Device IDs may get re-used when a device
        is removed.
    use
        If the device is a master pointer, 'use' is MasterPointer.
        If the device is a master keyboard, 'use' is MasterKeyboard.
        If the device is a slave pointer, 'use' is SlavePointer.
        If the device is a slave keyboard, 'use' is SlaveKeyboard.
        If the device is a floating slave, 'use' is FloatingSlave.

    attachment
        If the device is a master pointer or a master keyboard, 'attachment'
        specifies the paired master keyboard, or the paired master pointer,
        respectively.  If the device is a non-floating slave device
        'attachment' specifies the master device this device is attached to.
        If the device is a floating slave, 'attachment' is undefined.

    enabled
        Zero if the device is disabled, non-zero otherwise.
    num_classes
        Number of 'classes' provided.
    name_len
        Length of the name in bytes.
    classes
        Details the available classes provided by the device in an undefined
        order.
    name
        The device's name, padded to a multiple of 4 bytes.

    For all classes, 'type' specifies the device class. Clients are required
    to ignore unknown device classes. The 'length' field specifies the length
    of the class in 4 byte units.
    The following classes may occur only once: ButtonClass, KeyClass

    ButtonClass:
    type
        Always ButtonClass.
    length
        Length in 4 byte units.
    num_buttons
        Number of buttons provided by the device.
    buttons
        List of Atoms specifying the type of each button. An atom of None
        specifies an unnamed button. Buttons are listed in the device-native
        order and potential button mappings are ignored.

    KeyClass:
    type
        Always KeyClass.
    length
        Length in 4 byte units.
    num_keys
        Number of keycodes provided by the device.
    keys
        List of keycodes provided.

    AxisClass:
    type
        Always AxisClass.
    length
        Length in 4 byte units.
    axisnumber
        Axis number of this axis. The axis number is in device-native
        order and potential axis mappings are ignored.
    axisname
        Atom specifying the axis name. An Atom of None specifies an unnamed
        axis.
    min
        Minimum value.
    max
        Minimum value.
    resolution
        Resolution in counts/meter.
    mode
        Relative or Absolute.

    An axis in Relative mode may specify 'min' and 'max' as a hint to the
    client. If no 'min' and 'max' information is available, both must be 0.

    ┌───
        XISelectEvents
            window:         Window
            num_masks:      CARD16
            masks:          LISTofDEVICEEVENTMASK

    └───

    DEVICEEVENTMASK { deviceid:          DEVICE,
                      mask_len:          CARD16,
                      mask:              SETofEVENTMASK

    window
        The window to select the events on.
    num_masks
        Number of items in mask.
    deviceid
        Numerical deviceid, or AllDevices, or AllMasterDevices.
    mask_len
        Length of mask in 4 byte units.
    mask
        Event mask. An event mask for an event type T is defined as (1 << T).

    XISelectEvents selects for XI2 events on 'window'.

    If 'num_masks' is 0, a BadValue error occurs.

    Each 'mask' sets the (and overwrites a previous) event mask for the DEVICE
    specified through 'deviceid'. The device 'AllDevices' or
    'AllMasterDevices' is treated as a separate device by server. A client's
    event mask is the union of 'AllDevices', 'AllMasterDevices' and the
    per-device event mask.
    The removal of device from the server unsets the event masks for the
    device. If an event mask is set for AllDevices or AllMasterDevices, the
    event mask is not cleared on device removal and affects all future
    devices.

    If 'mask_len' is 0, the event mask for the given device is cleared.

    ┌───
        XIQueryDevicePointer
            window:         Window
            deviceid:       DEVICEID
            ▶
            root:           Window
            child:          Window
            root_x:         FP1616
            root_y:         FP1616
            win_x:          FP1616
            win_y:          FP1616
            same_screen:    BOOL
    └───

    Query a master pointer device for its current position.

    root
        The root window the pointer is logically on.
    child
        The child window of 'window' that contains the pointer or None.
    root_x
    root_y
        Pointer position relative to the root window's origin.
    win_x
    win_y
        Pointer position relative to 'window' or 0 if 'same_screen' is false.
    same_screen
        TRUE if 'window' is on the same screen as the pointer.

    ┌───
        XIWarpDevicePointer
            src_win:         Window
            dst_win:         Window
            src_x:           FP1616
            src_y:           FP1616
            src_width:       INT16
            src_height:      INT16
            dst_x:           FP1616
            dst_y:           FP1616
            deviceid:        DEVICEID
    └───

    WarpDevicePointer moves the pointer of 'deviceid' as if the user had moved
    the pointer. WarpDevicePointer can only be called for MasterPointer and
    FloatingSlave devices.

    src_win
       If src_window is not None, the move only takes place if src_window
       contains the pointer and the pointer is contained in the specified
       rectangle of src_window.
    dst_win
       If dst_win is None, this request moves the pointer by offsets
       'dst_x'/'dst_y' relative to the current position of the pointer. If
        dst_window is a window, this request moves the pointer to
       'dst_x'/'dst_y' relative to dst_win's origin.
    src_x
    src_y
    src_width
    src_height
       Specifies the source window rectangle.
    dst_x
    dst_y
        The relative coordinates to move the pointer if 'dst_win' is None, or
        the absolute coordinates if 'dst_win' is a window.
    deviceid
        The device to warp.

    This request cannot be used to move the pointer outside the confine-to
    window of an active pointer grab. An attempt will only move the pointer as
    far as the closest edge of the confine-to window.

    This request will generate events just as if the user had instantaneously
    moved the pointer.

    ┌───
        XIChangeDeviceCursor
            win:             Window
            cursor:          Cursor
            deviceid:        DEVICEID
    └───

    Change a master pointer's cursor on the specified window.

    window
        The window.
    cursor
        The new cursor or None.
    deviceid
        The master pointer device.

    Whenever 'device' enters a window W, the cursor shape is selected in the
    following order:
    - if the current window has a device cursor C(d) defined for 'device',
      display this cursor C(d).
    - otherwise, if the current window has a cursor C(w) defined in the core
      protocol's window attributes, display cursor C(w).
    - repeat on parent window until a cursor has been found.

    ┌───
        XIChangeDeviceHierarchy
            num_changes:     CARD8
            changes:         LISTofHIERARCHYCHANGES
    └───

    HIERARCHYCHANGE { CREATEMASTER, REMOVEMASTER, ATTACHSLAVE, DETACHSLAVE }

    HIERARCHYCHANGETYPE { CreateMaster, RemoveMaster, AttachSlave, DetachSlave }

    CHANGEMODE { Float, Attach }

    CREATEMASTER { type:        HIERARCHYCHANGETYPE
                   length:      CARD16
                   name_len:    CARD16
                   send_core:   BOOL
                   enable:      BOOL
                   name:        LISTofCHAR8 }

    REMOVEMASTER { type:            HIERARCHYCHANGETYPE
                   length:          CARD16
                   deviceid:        DEVICEID
                   return_mode:     CHANGEMODE
                   return_pointer:  DEVICEID
                   return_keyboard: DEVICEID }

    ATTACHSLAVE   { type:        HIERARCHYCHANGETYPE
                    length:      CARD16
                    deviceid:    DEVICEID
                    master:      DEVICEID }

    DETACHSLAVE { type:       HIERARCHYCHANGETYPE
                  length:     CARD16
                  deviceid:   DEVICEID }

    XIChangeDeviceHierarchy allows a client to modify the MD/SD device
    hierarchy (see Section 4).

    num_changes
        The number of changes to apply to the current hierarchy.
    changes
        The list of changes.

    The server processes the changes one by one and applies changes
    immediately. If an error occurs, processing stops at the current change
    and returns the number of successfully applied changes in the error.

    CREATEMASTER creates a pair of master devices.
    type
        Always CreateMaster.
    length
        Length in 4 byte units.
    name_len
        Length of 'name' in bytes.
    send_core
        TRUE if the device should send core events.
    enable
        TRUE if the device is to be enabled immediately.
    name
        The name for the new master devices. The master pointer's name is
        automatically appended with " pointer", the master keyboard's name is
        automatically appended with " keyboard".

    REMOVEMASTER removes an existing master device.
    type
        Always RemoveMaster.
    length
        Length in 4 byte units.
    deviceid
        The device to remove.
    return_mode
        Return mode for attached slave devices.
        If 'return_mode' is Float, all slave devices are set to floating.
        If 'return_mode' is Attach, slave pointers are attached to
        'return_pointer' and slave keyboards are attached to
        'return_keyboard'.
    return_pointer
    return_keyboard
        The master pointer and master keyboard to attach slave devices to, if
        'return_mode' is Attach.

    Removing a master pointer removes the paired master keyboard and vice
    versa.

    ATTACHSLAVE attaches a slave device to a given master device.
    type
        Always ChangeAttachment.
    length
        Length in 4 byte units.
    deviceid
        Deviceid of the slave device.
    master
        The new master device to attach this slave device to.

    DETACHSLAVE detaches a slave device from its current master device.
    type
        Always ChangeAttachment.
    length
        Length in 4 byte units.
    deviceid
        Deviceid of the slave device.

    ┌───
        XISetClientPointer
            win:             Window
            deviceid:        DEVICEID
    └───

    Set the ClientPointer for the client owning 'win' to the given device.

    win
         Window or client ID.
    deviceid
         The master pointer or master keyboard that acts as ClientPointer.

    Some protocol requests are ambiguous and the server has to choose a device
    to provide data for a request or a reply. By default, the server will
    choose a client's ClientPointer device to provide the data, unless the
    client currently has a grab on another device.

    ┌───
        XIGetClientPointer
            win:             Window
            ▶
            set:             BOOL
            deviceid:        DEVICEID
    └───

    Query the ClientPointer for the client owning 'win'.

    win
        The window or client ID.
    set
        TRUE if the client has an explicitly set ClientPointer.
    deviceid
        The master pointer that acts as a ClientPointer if 'set' is TRUE.

8. Events:

An event specifies its length in 4-byte units after the initial 32 bytes.
Future versions of the protocol may provide additional information
in the same event, thus increasing the event size. Clients are required to
always read the number of bytes specified by the event, not the size of the
event they may have been compiled against.


The following event types are available in XI2.

Version 2.0:
        HierarchyChanged
        DeviceChanged
        KeyPress
        KeyRelease
        ButtonPress
        ButtonRelease
        Motion
        RawEvent
        Enter
        Leave

All events have a set of common fields specified as EVENTHEADER.


EVENTHEADER { type:                       BYTE
              extension:                  BYTE
              sequenceNumber:             CARD16
              length:                     CARD32
              evtype:                     CARD16
              deviceid:                   DEVICEID
              time:                       Time }

    type
        Always GenericEvent.
    extension
        Always the X Input extension offset.
    sequenceNumber
        Sequence number of last request processed by the server.
    length
        Length in 4-byte units after the initial 32 bytes.
    evtype
        XI-specific event type.
    deviceid
        Numerical device id for a device.
    time
        Time in ms.


    ┌───
        DeviceHierarchyEvent:
            EVENTHEADER
            flags:                      SETofHIERARCHYMASK
            num_devices:                CARD16
            deviceinfo:                 LISTofHIERARCHYINFO
    └───


    HIERARCHYMASK { MasterAdded, MasterRemoved, SlaveAttached, SlaveDetached,
                    SlaveAdded, SlaveRemoved, DeviceEnabled, DeviceDisabled }

    HIERARCHYINFO { deviceid:           DEVICEID,
                    attachment:         DEVICEID,
                    type:               DEVICEUSE
                    enabled:            BOOL }

    flags
        Set of the changes that have occured, causing this event.
    num_devices
        The number of devices present in the hierarchy.
    devices
        The current hierarchy layout for each device.

    An XDeviceHierarchyEvent is sent whenever the device hierarchy been
    changed. The 'flags' specify all types of hierarchy modifiations that have
    occured.
    For all devices, 'deviceinfo' details the hierarchy information after the
    modification of the hierarchy has occured. For each device specified with
    'deviceid':
    - if 'type' is MasterPointer or MasterKeyboard, 'attachment' decribes the
      pairing of this device.
    - if 'type' is SlavePointer or SlaveKeyboard, 'attachment' describes the
      master device this device is attached to.
    - if 'type' is FloatingSlave device, 'attachment' is undefined.

    enabled
         TRUE if the device is enabled and can send events. A disabled master
         device will not forward events from an attached, enabled slave
         device.

    Note: Multiple devices may be affected in one hierarchy change,
    'deviceid' in an XDeviceHierarchyChangedEvent is always the first affected
    device. Clients should ignore deviceid and instead use the 'devices' list.

    ┌───
        DeviceChangedEvent:
            EVENTHEADER
            reason:                CHANGEREASON
            source:                DEVICEID
            num_classes:           CARD16
            classes:               LISTofCLASS
    └───

    CHANGEREASON { SlaveSwitch, DeviceChange }

    A DeviceChangeEvent is sent whenever a device changes it's capabilities.
    This can happen either by a new slave device sending events through a
    master device, or by a physical device changing capabilities at runtime.

    reason
        The reason for generating this event.
        If 'reason' is SlaveSwitch, the slave device sending events through
        this device has changed and 'source' specifies the new slave device.
        A SlaveSwitch 'reason' can only occur on a master device.
        If 'reason' is DeviceChange, the device itself has changed through
        other means (e.g. a physical device change) and 'source' is
        undefined. A DeviceChange can only occur on a slave device.
    source
        The source of the new classes. Only defined in 'reason' is
        SlaveSwitch.
    num_classes
        Number of 'classes' provided.
    classes
        Details the available classes provided by the device.  The order the
        classes are provided in is undefined.

    For a detailed description of 'classes', see the XQueryInputDevice
    request.

    ┌───
        DeviceEvent:
            EVENTHEADER
            detail:                     CARD32
            root:                       Window
            event:                      Window
            child:                      Window
            root_x:                     FP1616
            root_y:                     FP1616
            event_x:                    FP1616
            event_y:                    FP1616
            buttons_len:                CARD16
            valuators_len:              CARD16
            sourceid:                   DEVICEID
            mods:                       MODIFIERINFO
            group:                      GROUPINFO
            buttons:                    SETofBUTTONMASK
            valuators:                  SETofVALUATORMASK
            axisvalues:                 LISTofFP3232
    └───

    BUTTONBIT { (1 << Button1), (1 << Button2), ... , (1 << ButtonN) }
    VALUATORBIT { (1 << 1), ( 1 << 2), ... ( 1 << n) }

    MODIFIERINFO  { base_mods:           CARD32,
                    latched_mods:        CARD32,
                    locked_mods:         CARD32}
    GROUPINFO     { base_group:          CARD8,
                    latched_group:       CARD8,
                    locked_group:        CARD8 }

    An XDeviceEvent is generated whenever the logical state of a device
    changes in response to a button press, a button release, a motion, a key
    press or a key release.

    detail
        The button number or key code, or 0.
    root
    event
    child
        The root window, event window or subwindow, respectively. See core
        protocol specification for more detail.
    root_x
    root_y
        The position of the pointer in screen coordinates (16.16 fixed point).
    event_x
    event_y
        The position of the pointer in screen coordinates relative to the
        event window (16.16 fixed point).

    buttons_len
        The length of 'buttons' in 4 byte units.
    valuators_len
        The length of 'valuators' in 4 byte units.
    sourceid
        The source device that originally generated the event.
    mods
        XKB modifier state before the event occured.
    group
        XKB group state before the event.
    buttons
        Button state before the event.
    valuators
        Bitmask of valuators provided in 'axisvalues'.
    axisvalues
        Valuator data in device-native resolution.

    Modifier state in 'mods' is detailed as follows:
    base_mods
        XKB base modifier state.
    latched_mods
        XKB latched modifier state.
    locked_mods
        XKB locked modifier state.

    Group state in 'group' is detailed as follows:
    base_group
        XKB base group state.
    latched_group
        XKB latched group state.
    locked_group
        XKB locked group state.

    ┌───
        RawEvent
            EVENTHEADER
            eventtype:                 RAWTYPE
            detail:                    CARD32
            buttons_len:               CARD16
            valuators_len:             CARD16
            buttons:                   SETofBUTTONMASK
            valuators:                 SETofVALUATORMASK
            axisvalues:                LISTofFP3232
            axisvalues_raw:            LISTofFP3232
    └───

    RAWTYPE { Motion, KeyPress, KeyRelease, ButtonPress, ButtonRelease }

    A RawDevice event provides the information provided by the driver to the
    client. RawDevice events are only generated for slave devices and provide
    both the raw data as supplied by the driver and transformed data as used
    in the server. Transformations include, but are not limited to, axis
    clipping and acceleration.
    Transformed valuator data may be equivalent to raw data. In this case,
    both raw and transformed valuator data is provided.
    RawDeviceEvents are sent exclusively to all root windows or to the client
    that grabbed the device only.

    eventtype
        The type of event that occured on the device.
    detail
        The button number or keycode.
    buttons_len
        The length of 'buttons' in 4 byte units.
    valuators_len
        The length of 'valuators' in 4 byte units.
    buttons
        Button state before the event.
    valuators
        Bitmask of valuators provided in 'axisvalues' and 'axisvalues_raw'.
    axisvalues
        Valuator data in device-native resolution.
    axisvalues_raw
        Untransformed valuator data in device-native resolution.

    ┌───
        Enter or Leave
            EVENTHEADER
            root:               Window
            event:              Window
            child:              Window
            sourceid:           DEVICEID
            root_x:             FP1616
            root_y:             FP1616
            event_x             FP1616
            event_y:            FP1616
            mode:               NOTIFYMODE
            detail:             NOTIFYDETAIL
            same_screen:        BOOL
            focus:              BOOL
    └───

    NOTIFYMODE { Normal, Grab, Ungrab }
    NOTIFYDETAIL { Ancestor, Virtual, Inferior, Nonlinear, NonlinearVirtual,
                   Pointer, PointerRoot, None }

    Enter or Leave events are sent whenever a device's pointer enters or
    leaves a window.
    The enter/leave model is described in the core protocol specification,
    Section 11. (EnterNotify, LeaveNotify events).

    root
    event
    child
        The root window, event window, and child window, respectively. See the
        core protocol specification for more detail.
    sourceid
        The device that caused the pointer to move.
    root_x
    root_y
        The pointer coordinates relative to the root window.
    event_x
    event_y
        The pointer coordinates relative to the event window.
    mode
        Normal pointer motion events have mode Normal. Pseudo-motion events
        when a grab activates have mode Grab, and pseudo-motion events when a
        grab deactivates have mode Ungrab.
    detail
        Specifies the relation of the event window to the window the pointer
        entered or left. See the core protocol spec for details.
    same_screen
        TRUE if the event window is on the same screen as the pointer's root
        window.
    focus
        If the event window is the focus window or an inferior of the focus
        window, then focus is True. Otherwise, focus is False.

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