GdkDeviceManager: some reshuffling of docs

1 files changed, 58 insertions, 32 deletions

diff --git a/gdk/gdkdevicemanager.c b/gdk/gdkdevicemanager.c
index e736f8fa9a..301e790f83 100644
--- a/gdk/gdkdevicemanager.c
+++ b/gdk/gdkdevicemanager.c
@@ -33,18 +33,37 @@
  * In addition to a single pointer and keyboard for user interface input,
  * GDK contains support for a variety of input devices, including graphics
  * tablets, touchscreens and multiple pointers/keyboards interacting
- * simultaneously with the user interface. Under X, the support for multiple
- * input devices is done through the <firstterm>XInput 2</firstterm> extension,
- * which also supports additional features such as sub-pixel positioning
- * information and additional device-dependent information.
+ * simultaneously with the user interface. Such input devices often have
+ * additional features, such as sub-pixel positioning information and
+ * additional device-dependent information.
+ *
+ * In order to query the device hierarchy and be aware of changes in the
+ * device hierarchy (such as virtual devices being created or removed, or
+ * physical devices being plugged or unplugged), GDK provides
+ * #GdkDeviceManager.
  *
  * By default, and if the platform supports it, GDK is aware of multiple
- * keyboard/pointer pairs and multitouch devices, this behavior can be
- * changed by calling gdk_disable_multidevice() before gdk_display_open(),
- * although there would rarely be a reason to do that. For a widget or
- * window to be dealt as multipointer aware,
- * gdk_window_set_support_multidevice() or
- * gtk_widget_set_support_multidevice() must have been called on it.
+ * keyboard/pointer pairs and multitouch devices. This behavior can be
+ * changed by calling gdk_disable_multidevice() before gdk_display_open().
+ * There should rarely be a need to do that though, since GDK defaults
+ * to a compatibility mode in which it will emit just one enter/leave
+ * event pair for all devices on a window. To enable per-device
+ * enter/leave events and other multi-pointer interaction features,
+ * gdk_window_set_support_multidevice() must be called on
+ * #GdkWindows (or gtk_widget_set_support_multidevice() on widgets).
+ * window. See the gdk_window_set_support_multidevice() documentation
+ * for more information.
+ *
+ * On X11, multi-device support is implemented through XInput 2.
+ * Unless gdk_disable_multidevice() is called, the XInput 2
+ * #GdkDeviceManager implementation will be used as the input source.
+ * Otherwise either the core or XInput 1 implementations will be used.
+ *
+ * For simple applications that don't have any special interest in
+ * input devices, the so-called <firstterm>client pointer</firstterm>
+ * provides a reasonable approximation to a simple setup with a single
+ * pointer and keyboard. The device that has been set as the client
+ * pointer can be accessed via gdk_device_manager_get_client_pointer().
  *
  * Conceptually, in multidevice mode there are 2 device types. Virtual
  * devices (or master devices) are represented by the pointer cursors
@@ -60,28 +79,43 @@
  * be controlling each of these virtual devices. Physical devices may also
  * be "floating", which means they are not attached to any virtual device.
  *
+ * <example><title>Master and slave devices</title>
+ * <screen>
+ * carlos@sacarino:~$ xinput list
+ * ⎡ Virtual core pointer                          id=2    [master pointer  (3)]
+ * ⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
+ * ⎜   ↳ Wacom ISDv4 E6 Pen stylus                 id=10   [slave  pointer  (2)]
+ * ⎜   ↳ Wacom ISDv4 E6 Finger touch               id=11   [slave  pointer  (2)]
+ * ⎜   ↳ SynPS/2 Synaptics TouchPad                id=13   [slave  pointer  (2)]
+ * ⎜   ↳ TPPS/2 IBM TrackPoint                     id=14   [slave  pointer  (2)]
+ * ⎜   ↳ Wacom ISDv4 E6 Pen eraser                 id=16   [slave  pointer  (2)]
+ * ⎣ Virtual core keyboard                         id=3    [master keyboard (2)]
+ *     ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
+ *     ↳ Power Button                              id=6    [slave  keyboard (3)]
+ *     ↳ Video Bus                                 id=7    [slave  keyboard (3)]
+ *     ↳ Sleep Button                              id=8    [slave  keyboard (3)]
+ *     ↳ Integrated Camera                         id=9    [slave  keyboard (3)]
+ *     ↳ AT Translated Set 2 keyboard              id=12   [slave  keyboard (3)]
+ *     ↳ ThinkPad Extra Buttons                    id=15   [slave  keyboard (3)]
+ * </screen>
+ * </example>
+ *
  * By default, GDK will automatically listen for events coming from all
  * master devices, setting the #GdkDevice for all events coming from input
- * devices,
- * <footnote>
- * Events containing device information are #GDK_MOTION_NOTIFY,
+ * devices. Events containing device information are #GDK_MOTION_NOTIFY,
  * #GDK_BUTTON_PRESS, #GDK_2BUTTON_PRESS, #GDK_3BUTTON_PRESS,
  * #GDK_BUTTON_RELEASE, #GDK_SCROLL, #GDK_KEY_PRESS, #GDK_KEY_RELEASE,
  * #GDK_ENTER_NOTIFY, #GDK_LEAVE_NOTIFY, #GDK_FOCUS_CHANGE,
  * #GDK_PROXIMITY_IN, #GDK_PROXIMITY_OUT, #GDK_DRAG_ENTER, #GDK_DRAG_LEAVE,
  * #GDK_DRAG_MOTION, #GDK_DRAG_STATUS, #GDK_DROP_START, #GDK_DROP_FINISHED
- * and #GDK_GRAB_BROKEN.
- * </footnote>
- * Although gdk_window_set_support_multidevice() must be called on
- * #GdkWindows in order to support additional features of multiple pointer
- * interaction, such as multiple per-device enter/leave events, the default
- * setting will emit just one enter/leave event pair for all devices on the
- * window. See gdk_window_set_support_multidevice() documentation for more
- * information.
+ * and #GDK_GRAB_BROKEN. When dealing with an event on a master device,
+ * it is possible to get the source (slave) device that the event originated
+ * from via gdk_event_get_source_device().
  *
- * In order to listen for events coming from other than a virtual device,
- * gdk_window_set_device_events() must be called. Generally, this function
- * can be used to modify the event mask for any given device.
+ * In order to listen for events coming from devices
+ * other than a virtual device, gdk_window_set_device_events() must be
+ * called. Generally, this function can be used to modify the event mask
+ * for any given device.
  *
  * Input devices may also provide additional information besides X/Y.
  * For example, graphics tablets may also provide pressure and X/Y tilt
@@ -95,14 +129,6 @@
  * Devices may also have associated <firstterm>keys</firstterm> or
  * macro buttons. Such keys can be globally set to map into normal X
  * keyboard events. The mapping is set using gdk_device_set_key().
- *
- * In order to query the device hierarchy and be aware of changes in the
- * device hierarchy (such as virtual devices being created or removed, or
- * physical devices being plugged or unplugged), GDK provides
- * #GdkDeviceManager. On X11, multidevice support is implemented through
- * XInput 2. Unless gdk_disable_multidevice() is called, the XInput 2.x
- * #GdkDeviceManager implementation will be used as the input source. Otherwise
- * either the core or XInput 1.x implementations will be used.
  */
 
 static void gdk_device_manager_set_property (GObject      *object,