gdk: Make GdkEvent structs/union opaque

All users are forced to deal with events as opaque pointers, only
using API to access the info.

1 files changed, 891 insertions, 0 deletions

diff --git a/gdk/gdkeventsprivate.h b/gdk/gdkeventsprivate.h
new file mode 100644
index 0000000000..24c1ea18e1
--- /dev/null
+++ b/gdk/gdkeventsprivate.h
@@ -0,0 +1,891 @@
+/* GDK - The GIMP Drawing Kit
+ * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
+ * file for a list of people on the GTK+ Team.  See the ChangeLog
+ * files for a list of changes.  These files are distributed with
+ * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
+ */
+
+#ifndef __GDK_EVENTS_PRIVATE_H__
+#define __GDK_EVENTS_PRIVATE_H__
+
+#include <gdk/gdktypes.h>
+#include <gdk/gdkdnd.h>
+#include <gdk/gdkdevice.h>
+#include <gdk/gdkdevicetool.h>
+
+/**
+ * GdkEventAny:
+ * @type: the type of the event.
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ *
+ * Contains the fields which are common to all event structs.
+ * Any event pointer can safely be cast to a pointer to a #GdkEventAny to
+ * access these fields.
+ */
+struct _GdkEventAny
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+};
+
+/**
+ * GdkEventExpose:
+ * @type: the type of the event (%GDK_EXPOSE or %GDK_DAMAGE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @area: bounding box of @region.
+ * @region: the region that needs to be redrawn.
+ * @count: the number of contiguous %GDK_EXPOSE events following this one.
+ *   The only use for this is “exposure compression”, i.e. handling all
+ *   contiguous %GDK_EXPOSE events in one go, though GDK performs some
+ *   exposure compression so this is not normally needed.
+ *
+ * Generated when all or part of a window becomes visible and needs to be
+ * redrawn.
+ */
+struct _GdkEventExpose
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkRectangle area;
+  cairo_region_t *region;
+  gint count; /* If non-zero, how many more events follow. */
+};
+
+/**
+ * GdkEventVisibility:
+ * @type: the type of the event (%GDK_VISIBILITY_NOTIFY).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @state: the new visibility state (%GDK_VISIBILITY_FULLY_OBSCURED,
+ *   %GDK_VISIBILITY_PARTIAL or %GDK_VISIBILITY_UNOBSCURED).
+ *
+ * Generated when the window visibility status has changed.
+ *
+ * Deprecated: 3.12: Modern composited windowing systems with pervasive
+ *     transparency make it impossible to track the visibility of a window
+ *     reliably, so this event can not be guaranteed to provide useful
+ *     information.
+ */
+struct _GdkEventVisibility
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkVisibilityState state;
+};
+
+/**
+ * GdkEventMotion:
+ * @type: the type of the event.
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @x: the x coordinate of the pointer relative to the window.
+ * @y: the y coordinate of the pointer relative to the window.
+ * @axes: @x, @y translated to the axes of @device, or %NULL if @device is
+ *   the mouse.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ * @is_hint: set to 1 if this event is just a hint, see the
+ *   %GDK_POINTER_MOTION_HINT_MASK value of #GdkEventMask.
+ * @device: the master device that the event originated from. Use
+ * gdk_event_get_source_device() to get the slave device.
+ * @x_root: the x coordinate of the pointer relative to the root of the
+ *   screen.
+ * @y_root: the y coordinate of the pointer relative to the root of the
+ *   screen.
+ *
+ * Generated when the pointer moves.
+ */
+struct _GdkEventMotion
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  gdouble *axes;
+  guint state;
+  gint16 is_hint;
+  GdkDevice *device;
+  gdouble x_root, y_root;
+};
+
+/**
+ * GdkEventButton:
+ * @type: the type of the event (%GDK_BUTTON_PRESS, %GDK_2BUTTON_PRESS,
+ *   %GDK_3BUTTON_PRESS or %GDK_BUTTON_RELEASE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @x: the x coordinate of the pointer relative to the window.
+ * @y: the y coordinate of the pointer relative to the window.
+ * @axes: @x, @y translated to the axes of @device, or %NULL if @device is
+ *   the mouse.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ * @button: the button which was pressed or released, numbered from 1 to 5.
+ *   Normally button 1 is the left mouse button, 2 is the middle button,
+ *   and 3 is the right button. On 2-button mice, the middle button can
+ *   often be simulated by pressing both mouse buttons together.
+ * @device: the master device that the event originated from. Use
+ * gdk_event_get_source_device() to get the slave device.
+ * @x_root: the x coordinate of the pointer relative to the root of the
+ *   screen.
+ * @y_root: the y coordinate of the pointer relative to the root of the
+ *   screen.
+ *
+ * Used for button press and button release events. The
+ * @type field will be one of %GDK_BUTTON_PRESS,
+ * %GDK_2BUTTON_PRESS, %GDK_3BUTTON_PRESS or %GDK_BUTTON_RELEASE,
+ *
+ * Double and triple-clicks result in a sequence of events being received.
+ * For double-clicks the order of events will be:
+ *
+ * - %GDK_BUTTON_PRESS
+ * - %GDK_BUTTON_RELEASE
+ * - %GDK_BUTTON_PRESS
+ * - %GDK_2BUTTON_PRESS
+ * - %GDK_BUTTON_RELEASE
+ *
+ * Note that the first click is received just like a normal
+ * button press, while the second click results in a %GDK_2BUTTON_PRESS
+ * being received just after the %GDK_BUTTON_PRESS.
+ *
+ * Triple-clicks are very similar to double-clicks, except that
+ * %GDK_3BUTTON_PRESS is inserted after the third click. The order of the
+ * events is:
+ *
+ * - %GDK_BUTTON_PRESS
+ * - %GDK_BUTTON_RELEASE
+ * - %GDK_BUTTON_PRESS
+ * - %GDK_2BUTTON_PRESS
+ * - %GDK_BUTTON_RELEASE
+ * - %GDK_BUTTON_PRESS
+ * - %GDK_3BUTTON_PRESS
+ * - %GDK_BUTTON_RELEASE
+ *
+ * For a double click to occur, the second button press must occur within
+ * 1/4 of a second of the first. For a triple click to occur, the third
+ * button press must also occur within 1/2 second of the first button press.
+ */
+struct _GdkEventButton
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  gdouble *axes;
+  guint state;
+  guint button;
+  GdkDevice *device;
+  gdouble x_root, y_root;
+};
+
+/**
+ * GdkEventTouch:
+ * @type: the type of the event (%GDK_TOUCH_BEGIN, %GDK_TOUCH_UPDATE,
+ *   %GDK_TOUCH_END, %GDK_TOUCH_CANCEL)
+ * @window: the window which received the event
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @x: the x coordinate of the pointer relative to the window
+ * @y: the y coordinate of the pointer relative to the window
+ * @axes: @x, @y translated to the axes of @device, or %NULL if @device is
+ *   the mouse
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType
+ * @sequence: the event sequence that the event belongs to
+ * @emulating_pointer: whether the event should be used for emulating
+ *   pointer event
+ * @device: the master device that the event originated from. Use
+ * gdk_event_get_source_device() to get the slave device.
+ * @x_root: the x coordinate of the pointer relative to the root of the
+ *   screen
+ * @y_root: the y coordinate of the pointer relative to the root of the
+ *   screen
+ *
+ * Used for touch events.
+ * @type field will be one of %GDK_TOUCH_BEGIN, %GDK_TOUCH_UPDATE,
+ * %GDK_TOUCH_END or %GDK_TOUCH_CANCEL.
+ *
+ * Touch events are grouped into sequences by means of the @sequence
+ * field, which can also be obtained with gdk_event_get_event_sequence().
+ * Each sequence begins with a %GDK_TOUCH_BEGIN event, followed by
+ * any number of %GDK_TOUCH_UPDATE events, and ends with a %GDK_TOUCH_END
+ * (or %GDK_TOUCH_CANCEL) event. With multitouch devices, there may be
+ * several active sequences at the same time.
+ */
+struct _GdkEventTouch
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  gdouble *axes;
+  guint state;
+  GdkEventSequence *sequence;
+  gboolean emulating_pointer;
+  GdkDevice *device;
+  gdouble x_root, y_root;
+};
+
+/**
+ * GdkEventScroll:
+ * @type: the type of the event (%GDK_SCROLL).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @x: the x coordinate of the pointer relative to the window.
+ * @y: the y coordinate of the pointer relative to the window.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ * @direction: the direction to scroll to (one of %GDK_SCROLL_UP,
+ *   %GDK_SCROLL_DOWN, %GDK_SCROLL_LEFT, %GDK_SCROLL_RIGHT or
+ *   %GDK_SCROLL_SMOOTH).
+ * @device: the master device that the event originated from. Use
+ * gdk_event_get_source_device() to get the slave device.
+ * @x_root: the x coordinate of the pointer relative to the root of the
+ *   screen.
+ * @y_root: the y coordinate of the pointer relative to the root of the
+ *   screen.
+ * @delta_x: the x coordinate of the scroll delta
+ * @delta_y: the y coordinate of the scroll delta
+ *
+ * Generated from button presses for the buttons 4 to 7. Wheel mice are
+ * usually configured to generate button press events for buttons 4 and 5
+ * when the wheel is turned.
+ *
+ * Some GDK backends can also generate “smooth” scroll events, which
+ * can be recognized by the %GDK_SCROLL_SMOOTH scroll direction. For
+ * these, the scroll deltas can be obtained with
+ * gdk_event_get_scroll_deltas().
+ */
+struct _GdkEventScroll
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  guint state;
+  GdkScrollDirection direction;
+  GdkDevice *device;
+  gdouble x_root, y_root;
+  gdouble delta_x;
+  gdouble delta_y;
+  guint is_stop : 1;
+};
+
+/**
+ * GdkEventKey:
+ * @type: the type of the event (%GDK_KEY_PRESS or %GDK_KEY_RELEASE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ * @keyval: the key that was pressed or released. See the
+ *   `gdk/gdkkeysyms.h` header file for a
+ *   complete list of GDK key codes.
+ * @length: the length of @string.
+ * @string: a string containing an approximation of the text that
+ *   would result from this keypress. The only correct way to handle text
+ *   input of text is using input methods (see #GtkIMContext), so this
+ *   field is deprecated and should never be used.
+ *   (gdk_unicode_to_keyval() provides a non-deprecated way of getting
+ *   an approximate translation for a key.) The string is encoded in the
+ *   encoding of the current locale (Note: this for backwards compatibility:
+ *   strings in GTK+ and GDK are typically in UTF-8.) and NUL-terminated.
+ *   In some cases, the translation of the key code will be a single
+ *   NUL byte, in which case looking at @length is necessary to distinguish
+ *   it from the an empty translation.
+ * @hardware_keycode: the raw code of the key that was pressed or released.
+ * @group: the keyboard group.
+ * @is_modifier: a flag that indicates if @hardware_keycode is mapped to a
+ *   modifier. Since 2.10
+ *
+ * Describes a key press or key release event.
+ */
+struct _GdkEventKey
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  guint state;
+  guint keyval;
+  gint length;
+  gchar *string;
+  guint16 hardware_keycode;
+  guint8 group;
+  guint is_modifier : 1;
+};
+
+/**
+ * GdkEventCrossing:
+ * @type: the type of the event (%GDK_ENTER_NOTIFY or %GDK_LEAVE_NOTIFY).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @subwindow: the window that was entered or left.
+ * @time: the time of the event in milliseconds.
+ * @x: the x coordinate of the pointer relative to the window.
+ * @y: the y coordinate of the pointer relative to the window.
+ * @x_root: the x coordinate of the pointer relative to the root of the screen.
+ * @y_root: the y coordinate of the pointer relative to the root of the screen.
+ * @mode: the crossing mode (%GDK_CROSSING_NORMAL, %GDK_CROSSING_GRAB,
+ *  %GDK_CROSSING_UNGRAB, %GDK_CROSSING_GTK_GRAB, %GDK_CROSSING_GTK_UNGRAB or
+ *  %GDK_CROSSING_STATE_CHANGED).  %GDK_CROSSING_GTK_GRAB, %GDK_CROSSING_GTK_UNGRAB,
+ *  and %GDK_CROSSING_STATE_CHANGED were added in 2.14 and are always synthesized,
+ *  never native.
+ * @detail: the kind of crossing that happened (%GDK_NOTIFY_INFERIOR,
+ *  %GDK_NOTIFY_ANCESTOR, %GDK_NOTIFY_VIRTUAL, %GDK_NOTIFY_NONLINEAR or
+ *  %GDK_NOTIFY_NONLINEAR_VIRTUAL).
+ * @focus: %TRUE if @window is the focus window or an inferior.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ *
+ * Generated when the pointer enters or leaves a window.
+ */
+struct _GdkEventCrossing
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkWindow *subwindow;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  gdouble x_root;
+  gdouble y_root;
+  GdkCrossingMode mode;
+  GdkNotifyType detail;
+  gboolean focus;
+  guint state;
+};
+
+/**
+ * GdkEventFocus:
+ * @type: the type of the event (%GDK_FOCUS_CHANGE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @in: %TRUE if the window has gained the keyboard focus, %FALSE if
+ *   it has lost the focus.
+ *
+ * Describes a change of keyboard focus.
+ */
+struct _GdkEventFocus
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  gint16 in;
+};
+
+/**
+ * GdkEventConfigure:
+ * @type: the type of the event (%GDK_CONFIGURE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @x: the new x coordinate of the window, relative to its parent.
+ * @y: the new y coordinate of the window, relative to its parent.
+ * @width: the new width of the window.
+ * @height: the new height of the window.
+ *
+ * Generated when a window size or position has changed.
+ */
+struct _GdkEventConfigure
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  gint x, y;
+  gint width;
+  gint height;
+};
+
+/**
+ * GdkEventProperty:
+ * @type: the type of the event (%GDK_PROPERTY_NOTIFY).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @atom: the property that was changed.
+ * @time: the time of the event in milliseconds.
+ * @state: (type GdkPropertyState): whether the property was changed
+ *   (%GDK_PROPERTY_NEW_VALUE) or deleted (%GDK_PROPERTY_DELETE).
+ *
+ * Describes a property change on a window.
+ */
+struct _GdkEventProperty
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkAtom atom;
+  guint32 time;
+  guint state;
+};
+
+/**
+ * GdkEventSelection:
+ * @type: the type of the event (%GDK_SELECTION_CLEAR,
+ *   %GDK_SELECTION_NOTIFY or %GDK_SELECTION_REQUEST).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @selection: the selection.
+ * @target: the target to which the selection should be converted.
+ * @property: the property in which to place the result of the conversion.
+ * @time: the time of the event in milliseconds.
+ * @requestor: the window on which to place @property or %NULL if none.
+ *
+ * Generated when a selection is requested or ownership of a selection
+ * is taken over by another client application.
+ */
+struct _GdkEventSelection
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkAtom selection;
+  GdkAtom target;
+  GdkAtom property;
+  guint32 time;
+  GdkWindow *requestor;
+};
+
+/**
+ * GdkEventOwnerChange:
+ * @type: the type of the event (%GDK_OWNER_CHANGE).
+ * @window: the window which received the event
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @owner: the new owner of the selection, or %NULL if there is none
+ * @reason: the reason for the ownership change as a #GdkOwnerChange value
+ * @selection: the atom identifying the selection
+ * @time: the timestamp of the event
+ * @selection_time: the time at which the selection ownership was taken
+ *   over
+ *
+ * Generated when the owner of a selection changes. On X11, this
+ * information is only available if the X server supports the XFIXES
+ * extension.
+ *
+ * Since: 2.6
+ */
+struct _GdkEventOwnerChange
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkWindow *owner;
+  GdkOwnerChange reason;
+  GdkAtom selection;
+  guint32 time;
+  guint32 selection_time;
+};
+
+/**
+ * GdkEventProximity:
+ * @type: the type of the event (%GDK_PROXIMITY_IN or %GDK_PROXIMITY_OUT).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @device: the master device that the event originated from. Use
+ * gdk_event_get_source_device() to get the slave device.
+ *
+ * Proximity events are generated when using GDK’s wrapper for the
+ * XInput extension. The XInput extension is an add-on for standard X
+ * that allows you to use nonstandard devices such as graphics tablets.
+ * A proximity event indicates that the stylus has moved in or out of
+ * contact with the tablet, or perhaps that the user’s finger has moved
+ * in or out of contact with a touch screen.
+ *
+ * This event type will be used pretty rarely. It only is important for
+ * XInput aware programs that are drawing their own cursor.
+ */
+struct _GdkEventProximity
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  GdkDevice *device;
+};
+
+/**
+ * GdkEventSetting:
+ * @type: the type of the event (%GDK_SETTING).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @action: what happened to the setting (%GDK_SETTING_ACTION_NEW,
+ *   %GDK_SETTING_ACTION_CHANGED or %GDK_SETTING_ACTION_DELETED).
+ * @name: the name of the setting.
+ *
+ * Generated when a setting is modified.
+ */
+struct _GdkEventSetting
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkSettingAction action;
+  char *name;
+};
+
+/**
+ * GdkEventWindowState:
+ * @type: the type of the event (%GDK_WINDOW_STATE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @changed_mask: mask specifying what flags have changed.
+ * @new_window_state: the new window state, a combination of
+ *   #GdkWindowState bits.
+ *
+ * Generated when the state of a toplevel window changes.
+ */
+struct _GdkEventWindowState
+{
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkWindowState changed_mask;
+  GdkWindowState new_window_state;
+};
+
+/**
+ * GdkEventGrabBroken:
+ * @type: the type of the event (%GDK_GRAB_BROKEN)
+ * @window: the window which received the event, i.e. the window
+ *   that previously owned the grab
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @keyboard: %TRUE if a keyboard grab was broken, %FALSE if a pointer
+ *   grab was broken
+ * @implicit: %TRUE if the broken grab was implicit
+ * @grab_window: If this event is caused by another grab in the same
+ *   application, @grab_window contains the new grab window. Otherwise
+ *   @grab_window is %NULL.
+ *
+ * Generated when a pointer or keyboard grab is broken. On X11, this happens
+ * when the grab window becomes unviewable (i.e. it or one of its ancestors
+ * is unmapped), or if the same application grabs the pointer or keyboard
+ * again. Note that implicit grabs (which are initiated by button presses)
+ * can also cause #GdkEventGrabBroken events.
+ *
+ * Since: 2.8
+ */
+struct _GdkEventGrabBroken {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  gboolean keyboard;
+  gboolean implicit;
+  GdkWindow *grab_window;
+};
+
+/**
+ * GdkEventDND:
+ * @type: the type of the event (%GDK_DRAG_ENTER, %GDK_DRAG_LEAVE,
+ *   %GDK_DRAG_MOTION, %GDK_DRAG_STATUS, %GDK_DROP_START or
+ *   %GDK_DROP_FINISHED).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @context: the #GdkDragContext for the current DND operation.
+ * @time: the time of the event in milliseconds.
+ * @x_root: the x coordinate of the pointer relative to the root of the
+ *   screen, only set for %GDK_DRAG_MOTION and %GDK_DROP_START.
+ * @y_root: the y coordinate of the pointer relative to the root of the
+ *   screen, only set for %GDK_DRAG_MOTION and %GDK_DROP_START.
+ *
+ * Generated during DND operations.
+ */
+struct _GdkEventDND {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  GdkDragContext *context;
+
+  guint32 time;
+  gshort x_root, y_root;
+};
+
+/**
+ * GdkEventTouchpadSwipe:
+ * @type: the type of the event (%GDK_TOUCHPAD_SWIPE)
+ * @window: the window which received the event
+ * @send_event: %TRUE if the event was sent explicitly
+ * @phase: (type GdkTouchpadGesturePhase): the current phase of the gesture
+ * @n_fingers: The number of fingers triggering the swipe
+ * @time: the time of the event in milliseconds
+ * @x: The X coordinate of the pointer
+ * @y: The Y coordinate of the pointer
+ * @dx: Movement delta in the X axis of the swipe focal point
+ * @dy: Movement delta in the Y axis of the swipe focal point
+ * @x_root: The X coordinate of the pointer, relative to the
+ *   root of the screen.
+ * @y_root: The Y coordinate of the pointer, relative to the
+ *   root of the screen.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ *
+ * Generated during touchpad swipe gestures.
+ */
+struct _GdkEventTouchpadSwipe {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  gint8 phase;
+  gint8 n_fingers;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  gdouble dx;
+  gdouble dy;
+  gdouble x_root, y_root;
+  guint state;
+};
+
+/**
+ * GdkEventTouchpadPinch:
+ * @type: the type of the event (%GDK_TOUCHPAD_PINCH)
+ * @window: the window which received the event
+ * @send_event: %TRUE if the event was sent explicitly
+ * @phase: (type GdkTouchpadGesturePhase): the current phase of the gesture
+ * @n_fingers: The number of fingers triggering the pinch
+ * @time: the time of the event in milliseconds
+ * @x: The X coordinate of the pointer
+ * @y: The Y coordinate of the pointer
+ * @dx: Movement delta in the X axis of the swipe focal point
+ * @dy: Movement delta in the Y axis of the swipe focal point
+ * @angle_delta: The angle change in radians, negative angles
+ *   denote counter-clockwise movements
+ * @scale: The current scale, relative to that at the time of
+ *   the corresponding %GDK_TOUCHPAD_GESTURE_PHASE_BEGIN event
+ * @x_root: The X coordinate of the pointer, relative to the
+ *   root of the screen.
+ * @y_root: The Y coordinate of the pointer, relative to the
+ *   root of the screen.
+ * @state: (type GdkModifierType): a bit-mask representing the state of
+ *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
+ *   buttons. See #GdkModifierType.
+ *
+ * Generated during touchpad swipe gestures.
+ */
+struct _GdkEventTouchpadPinch {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  gint8 phase;
+  gint8 n_fingers;
+  guint32 time;
+  gdouble x;
+  gdouble y;
+  gdouble dx;
+  gdouble dy;
+  gdouble angle_delta;
+  gdouble scale;
+  gdouble x_root, y_root;
+  guint state;
+};
+
+/**
+ * GdkEventPadButton:
+ * @type: the type of the event (%GDK_PAD_BUTTON_PRESS or %GDK_PAD_BUTTON_RELEASE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @group: the pad group the button belongs to. A %GDK_SOURCE_TABLET_PAD device
+ *   may have one or more groups containing a set of buttons/rings/strips each.
+ * @button: The pad button that was pressed.
+ * @mode: The current mode of @group. Different groups in a %GDK_SOURCE_TABLET_PAD
+ *   device may have different current modes.
+ *
+ * Generated during %GDK_SOURCE_TABLET_PAD button presses and releases.
+ *
+ * Since: 3.22
+ */
+struct _GdkEventPadButton {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  guint group;
+  guint button;
+  guint mode;
+};
+
+/**
+ * GdkEventPadAxis:
+ * @type: the type of the event (%GDK_PAD_RING or %GDK_PAD_STRIP).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @group: the pad group the ring/strip belongs to. A %GDK_SOURCE_TABLET_PAD
+ *   device may have one or more groups containing a set of buttons/rings/strips
+ *   each.
+ * @index: number of strip/ring that was interacted. This number is 0-indexed.
+ * @mode: The current mode of @group. Different groups in a %GDK_SOURCE_TABLET_PAD
+ *   device may have different current modes.
+ * @value: The current value for the given axis.
+ *
+ * Generated during %GDK_SOURCE_TABLET_PAD interaction with tactile sensors.
+ *
+ * Since: 3.22
+ */
+struct _GdkEventPadAxis {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  guint group;
+  guint index;
+  guint mode;
+  gdouble value;
+};
+
+/**
+ * GdkEventPadGroupMode:
+ * @type: the type of the event (%GDK_PAD_GROUP_MODE).
+ * @window: the window which received the event.
+ * @send_event: %TRUE if the event was sent explicitly.
+ * @time: the time of the event in milliseconds.
+ * @group: the pad group that is switching mode. A %GDK_SOURCE_TABLET_PAD
+ *   device may have one or more groups containing a set of buttons/rings/strips
+ *   each.
+ * @mode: The new mode of @group. Different groups in a %GDK_SOURCE_TABLET_PAD
+ *   device may have different current modes.
+ *
+ * Generated during %GDK_SOURCE_TABLET_PAD mode switches in a group.
+ *
+ * Since: 3.22
+ */
+struct _GdkEventPadGroupMode {
+  GdkEventType type;
+  GdkWindow *window;
+  gint8 send_event;
+  guint32 time;
+  guint group;
+  guint mode;
+};
+
+/**
+ * GdkEvent:
+ * @type: the #GdkEventType
+ * @any: a #GdkEventAny
+ * @expose: a #GdkEventExpose
+ * @visibility: a #GdkEventVisibility
+ * @motion: a #GdkEventMotion
+ * @button: a #GdkEventButton
+ * @touch: a #GdkEventTouch
+ * @scroll: a #GdkEventScroll
+ * @key: a #GdkEventKey
+ * @crossing: a #GdkEventCrossing
+ * @focus_change: a #GdkEventFocus
+ * @configure: a #GdkEventConfigure
+ * @property: a #GdkEventProperty
+ * @selection: a #GdkEventSelection
+ * @owner_change: a #GdkEventOwnerChange
+ * @proximity: a #GdkEventProximity
+ * @dnd: a #GdkEventDND
+ * @window_state: a #GdkEventWindowState
+ * @setting: a #GdkEventSetting
+ * @grab_broken: a #GdkEventGrabBroken
+ * @touchpad_swipe: a #GdkEventTouchpadSwipe
+ * @touchpad_pinch: a #GdkEventTouchpadPinch
+ * @pad_button: a #GdkEventPadButton
+ * @pad_axis: a #GdkEventPadAxis
+ * @pad_group_mode: a #GdkEventPadGroupMode
+ *
+ * A #GdkEvent contains a union of all of the event types,
+ * and allows access to the data fields in a number of ways.
+ *
+ * The event type is always the first field in all of the event types, and
+ * can always be accessed with the following code, no matter what type of
+ * event it is:
+ * |[<!-- language="C" -->
+ *   GdkEvent *event;
+ *   GdkEventType type;
+ *
+ *   type = event->type;
+ * ]|
+ *
+ * To access other fields of the event, the pointer to the event
+ * can be cast to the appropriate event type, or the union member
+ * name can be used. For example if the event type is %GDK_BUTTON_PRESS
+ * then the x coordinate of the button press can be accessed with:
+ * |[<!-- language="C" -->
+ *   GdkEvent *event;
+ *   gdouble x;
+ *
+ *   x = ((GdkEventButton*)event)->x;
+ * ]|
+ * or:
+ * |[<!-- language="C" -->
+ *   GdkEvent *event;
+ *   gdouble x;
+ *
+ *   x = event->button.x;
+ * ]|
+ */
+union _GdkEvent
+{
+  GdkEventType		    type;
+  GdkEventAny		    any;
+  GdkEventExpose	    expose;
+  GdkEventVisibility	    visibility;
+  GdkEventMotion	    motion;
+  GdkEventButton	    button;
+  GdkEventTouch             touch;
+  GdkEventScroll            scroll;
+  GdkEventKey		    key;
+  GdkEventCrossing	    crossing;
+  GdkEventFocus		    focus_change;
+  GdkEventConfigure	    configure;
+  GdkEventProperty	    property;
+  GdkEventSelection	    selection;
+  GdkEventOwnerChange  	    owner_change;
+  GdkEventProximity	    proximity;
+  GdkEventDND               dnd;
+  GdkEventWindowState       window_state;
+  GdkEventSetting           setting;
+  GdkEventGrabBroken        grab_broken;
+  GdkEventTouchpadSwipe     touchpad_swipe;
+  GdkEventTouchpadPinch     touchpad_pinch;
+  GdkEventPadButton         pad_button;
+  GdkEventPadAxis           pad_axis;
+  GdkEventPadGroupMode      pad_group_mode;
+};
+
+#endif /* __GDK_EVENTS_PRIVATE_H__ */