X11 Specific Support: Clutter Reference Manual

## X11 Specific Support X11 Specific Support — X11 specific API |

## Functions

void | clutter_x11_set_display ()
void | clutter_x11_disable_event_retrieval ()
gboolean | clutter_x11_has_event_retrieval ()
ClutterStage * | clutter_x11_get_stage_from_window ()
ClutterX11FilterReturn | clutter_x11_handle_event ()
Display * | clutter_x11_get_default_display ()
int | clutter_x11_get_default_screen ()
Window | clutter_x11_get_root_window ()
XVisualInfo * | clutter_x11_get_stage_visual ()
Window | clutter_x11_get_stage_window ()
gboolean | clutter_x11_set_stage_foreign ()
void | clutter_x11_trap_x_errors ()
gint | clutter_x11_untrap_x_errors ()
gboolean | clutter_x11_has_composite_extension ()
Time | clutter_x11_get_current_event_time ()
void | clutter_x11_set_use_argb_visual ()
gboolean | clutter_x11_get_use_argb_visual ()
XVisualInfo * | clutter_x11_get_visual_info ()
gboolean | clutter_x11_get_use_stereo_stage ()
void | clutter_x11_set_use_stereo_stage ()
ClutterX11FilterReturn | (*ClutterX11FilterFunc) ()
void | clutter_x11_add_filter ()
void | clutter_x11_remove_filter ()
const GSList * | clutter_x11_get_input_devices ()
gboolean | clutter_x11_has_xinput ()
void | clutter_x11_enable_xinput ()
gint | clutter_x11_event_get_key_group ()
guint | clutter_x11_event_sequence_get_touch_detail ()

## Types and Values

enum | ClutterX11FilterReturn

## Description

The X11 backend for Clutter provides some specific API, allowing integration with the Xlibs API for embedding and manipulating the stage window, or for trapping X errors.

The ClutterX11 API is available since Clutter 0.6

## Functions

### clutter_x11_set_display ()

    void
    clutter_x11_set_display (Display *xdpy);

Sets the display connection Clutter should use; must be called before `clutter_init()`, `clutter_init_with_args()` or other functions pertaining Clutter's initialization process.

If you are parsing the command line arguments by retrieving Clutter's GOptionGroup with `clutter_get_option_group()` and calling `g_option_context_parse()` yourself, you should also call `clutter_x11_set_display()` before `g_option_context_parse()`.

#### Parameters

xdpy | pointer to a X display connection. |

Since: 0.8

### clutter_x11_disable_event_retrieval ()

    void
    clutter_x11_disable_event_retrieval (void);

Disables the internal polling of X11 events in the main loop.

Libraries or applications calling this function will be responsible of polling all X11 events.

You also must call `clutter_x11_handle_event()` to let Clutter process events and maintain its internal state.

This function can only be called before calling `clutter_init()`.

Even with event handling disabled, Clutter will still select all the events required to maintain its internal state on the stage Window; compositors using Clutter and input regions to pass events through to application windows should not rely on an empty input region, and should instead clear it themselves explicitly using the XFixes extension.

This function should not be normally used by applications.

Since: 0.8

### clutter_x11_has_event_retrieval ()

    gboolean
    clutter_x11_has_event_retrieval (void);

Queries the X11 backend to check if event collection has been disabled.

#### Returns

TRUE if event retrival has been disabled. FALSE otherwise.

Since: 0.8

### clutter_x11_get_stage_from_window ()

    ClutterStage *
    clutter_x11_get_stage_from_window (Window win);

Gets the stage for a particular X window.

#### Parameters

win | an X Window ID |

#### Returns

A ClutterStage, or% NULL if a stage does not exist for the window.

[transfer none]

Since: 0.8

### clutter_x11_handle_event ()

    ClutterX11FilterReturn
    clutter_x11_handle_event (XEvent *xevent);

This function processes a single X event; it can be used to hook into external X11 event processing (for example, a GDK filter function).

If `clutter_x11_disable_event_retrieval()` has been called, you must let this function process events to update Clutter's internal state.

#### Parameters

xevent | pointer to XEvent structure |

#### Returns

ClutterX11FilterReturn. `CLUTTER_X11_FILTER_REMOVE` indicates that Clutter has internally handled the event and the caller should do no further processing. `CLUTTER_X11_FILTER_CONTINUE` indicates that Clutter is either not interested in the event, or has used the event to update internal state without taking any exclusive action. `CLUTTER_X11_FILTER_TRANSLATE` will not occur.

Since: 0.8

### clutter_x11_get_default_display ()

    Display *
    clutter_x11_get_default_display (void);

Retrieves the pointer to the default display.

#### Returns

the default display.

[transfer none]

Since: 0.6

### clutter_x11_get_default_screen ()

    int
    clutter_x11_get_default_screen (void);

Gets the number of the default X Screen object.

#### Returns

the number of the default screen

Since: 0.6

### clutter_x11_get_root_window ()

    Window
    clutter_x11_get_root_window (void);

Retrieves the root window.

[skip]

#### Returns

the id of the root window

Since: 0.6

### clutter_x11_get_stage_visual ()

    XVisualInfo *
    clutter_x11_get_stage_visual (ClutterStage *stage);

`clutter_x11_get_stage_visual` has been deprecated since version 1.2 and should not be used in newly-written code.

Use `clutter_x11_get_visual_info()` instead

Returns an XVisualInfo suitable for creating a foreign window for the given stage. NOTE: It doesn't do as the name may suggest, which is return the XVisualInfo that was used to create an existing window for the given stage.

XXX: It might be best to deprecate this function and replace with something along the lines of `clutter_backend_x11_get_foreign_visual()` or perhaps `clutter_stage_x11_get_foreign_visual()`

[skip]

#### Parameters

stage | a ClutterStage |

#### Returns

An XVisualInfo suitable for creating a foreign stage. Use `XFree()` to free the returned value instead.

[transfer full]

Since: 0.4

### clutter_x11_get_stage_window ()

    Window
    clutter_x11_get_stage_window (ClutterStage *stage);

Gets the stages X Window.

[skip]

#### Parameters

stage | a ClutterStage |

#### Returns

An XID for the stage window.

Since: 0.4

### clutter_x11_set_stage_foreign ()

    gboolean
    clutter_x11_set_stage_foreign (ClutterStage *stage,
                                   Window xwindow);

Target the ClutterStage to use an existing external X Window

#### Parameters

stage | a ClutterStage |
xwindow | an existing X Window id |

#### Returns

`TRUE` if foreign window is valid

Since: 0.4

### clutter_x11_trap_x_errors ()

    void
    clutter_x11_trap_x_errors (void);

Traps every X error until `clutter_x11_untrap_x_errors()` is called.

Since: 0.6

### clutter_x11_untrap_x_errors ()

    gint
    clutter_x11_untrap_x_errors (void);

Removes the X error trap and returns the current status.

#### Returns

the trapped error code, or 0 for success

Since: 0.4

### clutter_x11_has_composite_extension ()

    gboolean
    clutter_x11_has_composite_extension (void);

Retrieves whether Clutter is running on an X11 server with the XComposite extension

#### Returns

`TRUE` if the XComposite extension is available

### clutter_x11_get_current_event_time ()

    Time
    clutter_x11_get_current_event_time (void);

Retrieves the timestamp of the last X11 event processed by Clutter. This might be different from the timestamp returned by `clutter_get_current_event_time()`, as Clutter may synthesize or throttle events.

[skip]

#### Returns

a timestamp, in milliseconds

Since: 1.0

### clutter_x11_set_use_argb_visual ()

    void
    clutter_x11_set_use_argb_visual (gboolean use_argb);

Sets whether the Clutter X11 backend should request ARGB visuals by default or not.

By default, Clutter requests RGB visuals.

If no ARGB visuals are found, the X11 backend will fall back to requesting a RGB visual instead.

ARGB visuals are required for the “use-alpha” property to work.

This function can only be called once, and before `clutter_init()` is called.

#### Parameters

use_argb | `TRUE` if ARGB visuals should be requested by default |

Since: 1.2

### clutter_x11_get_use_argb_visual ()

    gboolean
    clutter_x11_get_use_argb_visual (void);

Retrieves whether the Clutter X11 backend is using ARGB visuals by default

#### Returns

`TRUE` if ARGB visuals are queried by default

Since: 1.2

### clutter_x11_get_visual_info ()

    XVisualInfo *
    clutter_x11_get_visual_info (void);

Retrieves the `XVisualInfo` used by the Clutter X11 backend.

[skip]

#### Returns

a `XVisualInfo`, or `None`. The returned value should be freed using ``XFree()`` when done.

[transfer full]

Since: 1.2

### clutter_x11_get_use_stereo_stage ()

    gboolean
    clutter_x11_get_use_stereo_stage (void);

Retrieves whether the Clutter X11 backend will create stereo stages if possible.

#### Returns

`TRUE` if stereo stages are used if possible

Since: 1.22

### clutter_x11_set_use_stereo_stage ()

    void
    clutter_x11_set_use_stereo_stage (gboolean use_stereo);

Sets whether the backend object for Clutter stages, will, if possible, be created with the ability to support stereo drawing (drawing separate images for the left and right eyes).

This function must be called before `clutter_init()` is called. During paint callbacks, `cogl_framebuffer_is_stereo()` can be called on the framebuffer retrieved by `cogl_get_draw_framebuffer()` to determine if stereo support was successfully enabled, and `cogl_framebuffer_set_stereo_mode()` to determine which buffers will be drawn to.

Note that this function *does not* cause the stage to be drawn multiple times with different perspective transformations and thus appear in 3D, it simply enables individual ClutterActors to paint different images for the left and and right eye.

#### Parameters

use_stereo | `TRUE` if the stereo stages should be used if possible. |

Since: 1.22

### ClutterX11FilterFunc ()

    ClutterX11FilterReturn
    (*ClutterX11FilterFunc) (XEvent *xev,
                             ClutterEvent *cev,
                             gpointer data);

Filter function for X11 native events.

#### Parameters

xev | Native X11 event structure |
cev | Clutter event structure |
data | user data passed to the filter function. | [closure]

#### Returns

the result of the filtering

Since: 0.6

### clutter_x11_add_filter ()

    void
    clutter_x11_add_filter (ClutterX11FilterFunc func,
                            gpointer data);

Adds an event filter function.

[skip]

#### Parameters

func | a filter function |
data | user data to be passed to the filter function, or `NULL` |

Since: 0.6

### clutter_x11_remove_filter ()

    void
    clutter_x11_remove_filter (ClutterX11FilterFunc func,
                               gpointer data);

Removes the given filter function.

[skip]

#### Parameters

func | a filter function |
data | user data to be passed to the filter function, or `NULL` |

Since: 0.6

### clutter_x11_get_input_devices ()

    const GSList *
    clutter_x11_get_input_devices (void);

`clutter_x11_get_input_devices` has been deprecated since version 1.2 and should not be used in newly-written code.

Use `clutter_device_manager_peek_devices()` instead

Retrieves a pointer to the list of input devices

#### Returns

a pointer to the internal list of input devices; the returned list is owned by Clutter and should not be modified or freed.

[transfer none][element-type Clutter.InputDevice]

Since: 0.8

### clutter_x11_has_xinput ()

    gboolean
    clutter_x11_has_xinput (void);

Gets whether Clutter has XInput support.

#### Returns

`TRUE` if Clutter was compiled with XInput support and XInput support is available at run time.

Since: 0.8

### clutter_x11_enable_xinput ()

    void
    clutter_x11_enable_xinput (void);

`clutter_x11_enable_xinput` has been deprecated since version 1.14 and should not be used in newly-written code.

This function does not do anything; XInput support is enabled by default in Clutter. Use the CLUTTER_DISABLE_XINPUT environment variable to disable XInput support and use Xlib core events instead.

Enables the use of the XInput extension if present on connected XServer and support built into Clutter. XInput allows for multiple pointing devices to be used.

This function must be called before `clutter_init()`.

Since XInput might not be supported by the X server, you might want to use `clutter_x11_has_xinput()` to see if support was enabled.

Since: 0.8

### clutter_x11_event_get_key_group ()

    gint
    clutter_x11_event_get_key_group (const ClutterEvent *event);

Retrieves the group for the modifiers set in `event`

#### Parameters

event | a ClutterEvent of type `CLUTTER_KEY_PRESS` or `CLUTTER_KEY_RELEASE` |

#### Returns

the group id

Since: 1.4

### clutter_x11_event_sequence_get_touch_detail ()

    guint
    clutter_x11_event_sequence_get_touch_detail
                                   (const ClutterEventSequence *sequence);

Retrieves the touch detail froma ClutterEventSequence.

#### Parameters

sequence | a ClutterEventSequence |

#### Returns

the touch detail

Since: 1.12

## Types and Values

### enum ClutterX11FilterReturn

Return values for the ClutterX11FilterFunc function.

#### Members

CLUTTER_X11_FILTER_CONTINUE | The event was not handled, continues the processing |
CLUTTER_X11_FILTER_TRANSLATE | Native event translated into a Clutter event, stops the processing |
CLUTTER_X11_FILTER_REMOVE | Remove the event, stops the processing |

Since: 0.6