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Clutter Reference Manual | ![]() |
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Top | Description | Object Hierarchy | Signals |
ClutterBackend; ClutterBackend * clutter_get_default_backend (void
); void clutter_backend_set_resolution (ClutterBackend *backend
,gdouble dpi
); gdouble clutter_backend_get_resolution (ClutterBackend *backend
); void clutter_backend_set_double_click_time (ClutterBackend *backend
,guint msec
); guint clutter_backend_get_double_click_time (ClutterBackend *backend
); void clutter_backend_set_double_click_distance (ClutterBackend *backend
,guint distance
); guint clutter_backend_get_double_click_distance (ClutterBackend *backend
); void clutter_backend_set_font_options (ClutterBackend *backend
,const cairo_font_options_t *options
); const cairo_font_options_t * clutter_backend_get_font_options (ClutterBackend *backend
); void clutter_backend_set_font_name (ClutterBackend *backend
,const gchar *font_name
); const gchar * clutter_backend_get_font_name (ClutterBackend *backend
); CoglContext * clutter_backend_get_cogl_context (ClutterBackend *backend
); gboolean clutter_check_windowing_backend (const char *backend_type
);
Clutter can be compiled against different backends. Each backend has to implement a set of functions, in order to be used by Clutter.
ClutterBackend is the base class abstracting the various implementation; it provides a basic API to query the backend for generic information and settings.
ClutterBackend is available since Clutter 0.4
typedef struct _ClutterBackend ClutterBackend;
ClutterBackend is an opaque structure whose members cannot be directly accessed.
Since 0.4
ClutterBackend * clutter_get_default_backend (void
);
Retrieves the default ClutterBackend used by Clutter. The ClutterBackend holds backend-specific configuration options.
Returns : |
the default backend. You should not ref or unref the returned object. Applications should rarely need to use this. [transfer none] |
Since 0.4
void clutter_backend_set_resolution (ClutterBackend *backend
,gdouble dpi
);
clutter_backend_set_resolution
has been deprecated since version 1.4 and should not be used in newly-written code. Use "font-dpi" instead
Sets the resolution for font handling on the screen. This is a scale factor between points specified in a PangoFontDescription and cairo units. The default value is 96, meaning that a 10 point font will be 13 units high. (10 * 96. / 72. = 13.3).
Applications should never need to call this function.
|
a ClutterBackend |
|
the resolution in "dots per inch" (Physical inches aren't actually involved; the terminology is conventional). |
Since 0.4
gdouble clutter_backend_get_resolution (ClutterBackend *backend
);
Gets the resolution for font handling on the screen.
The resolution is a scale factor between points specified in a PangoFontDescription and cairo units. The default value is 96.0, meaning that a 10 point font will be 13 units high (10 * 96. / 72. = 13.3).
Clutter will set the resolution using the current backend when initializing; the resolution is also stored in the "font-dpi" property.
|
a ClutterBackend |
Returns : |
the current resolution, or -1 if no resolution has been set. |
Since 0.4
void clutter_backend_set_double_click_time (ClutterBackend *backend
,guint msec
);
clutter_backend_set_double_click_time
has been deprecated since version 1.4 and should not be used in newly-written code. Use "double-click-time" instead
Sets the maximum time between two button press events, used to verify whether it's a double click event or not.
|
a ClutterBackend |
|
milliseconds between two button press events |
Since 0.4
guint clutter_backend_get_double_click_time
(ClutterBackend *backend
);
clutter_backend_get_double_click_time
has been deprecated since version 1.4 and should not be used in newly-written code. Use "double-click-time" instead
Gets the maximum time between two button press events, as set
by clutter_backend_set_double_click_time()
.
|
a ClutterBackend |
Returns : |
a time in milliseconds |
Since 0.4
void clutter_backend_set_double_click_distance (ClutterBackend *backend
,guint distance
);
clutter_backend_set_double_click_distance
has been deprecated since version 1.4 and should not be used in newly-written code. Use "double-click-distance" instead
Sets the maximum distance used to verify a double click event.
|
a ClutterBackend |
|
a distance, in pixels |
Since 0.4
guint clutter_backend_get_double_click_distance
(ClutterBackend *backend
);
clutter_backend_get_double_click_distance
has been deprecated since version 1.4 and should not be used in newly-written code. Use "double-click-distance" instead
Retrieves the distance used to verify a double click event
|
a ClutterBackend |
Returns : |
a distance, in pixels. |
Since 0.4
void clutter_backend_set_font_options (ClutterBackend *backend
,const cairo_font_options_t *options
);
Sets the new font options for backend
. The ClutterBackend will
copy the cairo_font_options_t.
If options
is NULL
, the first following call to
clutter_backend_get_font_options()
will return the default font
options for backend
.
This function is intended for actors creating a Pango layout using the PangoCairo API.
|
a ClutterBackend |
|
Cairo font options for the backend, or NULL
|
Since 0.8
const cairo_font_options_t * clutter_backend_get_font_options
(ClutterBackend *backend
);
Retrieves the font options for backend
.
|
a ClutterBackend |
Returns : |
the font options of the ClutterBackend. The returned cairo_font_options_t is owned by the backend and should not be modified or freed. [transfer none] |
Since 0.8
void clutter_backend_set_font_name (ClutterBackend *backend
,const gchar *font_name
);
clutter_backend_set_font_name
has been deprecated since version 1.4 and should not be used in newly-written code. Use "font-name" instead
Sets the default font to be used by Clutter. The font_name
string
must either be NULL
, which means that the font name from the
default ClutterBackend will be used; or be something that can
be parsed by the pango_font_description_from_string()
function.
|
a ClutterBackend |
|
the name of the font |
Since 1.0
const gchar * clutter_backend_get_font_name (ClutterBackend *backend
);
clutter_backend_get_font_name
has been deprecated since version 1.4 and should not be used in newly-written code. Use "font-name" instead
Retrieves the default font name as set by
clutter_backend_set_font_name()
.
|
a ClutterBackend |
Returns : |
the font name for the backend. The returned string is owned by the ClutterBackend and should never be modified or freed |
Since 1.0
CoglContext * clutter_backend_get_cogl_context (ClutterBackend *backend
);
Retrieves the CoglContext associated with the given clutter
backend
. A CoglContext is required when using some of the
experimental 2.0 Cogl API.
|
a ClutterBackend |
Returns : |
The CoglContext associated with backend . |
Since 1.8
Stability Level: Unstable
gboolean clutter_check_windowing_backend (const char *backend_type
);
Checks the run-time name of the Clutter windowing system backend, using
the symbolic macros like CLUTTER_WINDOWING_WIN32
or
CLUTTER_WINDOWING_X11
.
This function should be used in conjuction with the compile-time macros inside applications and libraries that are using the platform-specific windowing system API, to ensure that they are running on the correct windowing system; for instance:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
#ifdef CLUTTER_WINDOWING_X11 if (clutter_check_windowing_backend (CLUTTER_WINDOWING_X11)) { /* it is safe to use the clutter_x11_* API */ } else #endif #ifdef CLUTTER_WINDOWING_WIN32 if (clutter_check_windowing_backend (CLUTTER_WINDOWING_WIN32)) { /* it is safe to use the clutter_win32_* API */ } else #endif g_error ("Unknown Clutter backend."); |
|
the name of the backend to check |
Returns : |
TRUE if the current Clutter windowing system backend is
the one checked, and FALSE otherwise |
Since 1.10
"font-changed"
signalvoid user_function (ClutterBackend *backend,
gpointer user_data) : Run First
The ::font-changed signal is emitted each time the font options have been changed through ClutterSettings.
|
the ClutterBackend that emitted the signal |
|
user data set when the signal handler was connected. |
Since 1.0
"resolution-changed"
signalvoid user_function (ClutterBackend *backend,
gpointer user_data) : Run First
The ::resolution-changed signal is emitted each time the font resolutions has been changed through ClutterSettings.
|
the ClutterBackend that emitted the signal |
|
user data set when the signal handler was connected. |
Since 1.0
"settings-changed"
signalvoid user_function (ClutterBackend *backend,
gpointer user_data) : Run First
The ::settings-changed signal is emitted each time the ClutterSettings properties have been changed.
|
the ClutterBackend that emitted the signal |
|
user data set when the signal handler was connected. |
Since 1.4