gtk/gdk/gdkscreen.c
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2014-02-19 18:56:05 -05:00

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/*
* gdkscreen.c
*
* Copyright 2001 Sun Microsystems Inc.
*
* Erwann Chenede <erwann.chenede@sun.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include "gdkinternals.h"
#include "gdkscreenprivate.h"
#include "gdkrectangle.h"
#include "gdkwindow.h"
#include "gdkintl.h"
/**
* SECTION:gdkscreen
* @Short_description: Object representing a physical screen
* @Title: GdkScreen
*
* #GdkScreen objects are the GDK representation of the screen on
* which windows can be displayed and on which the pointer moves.
* X originally identified screens with physical screens, but
* nowadays it is more common to have a single #GdkScreen which
* combines several physical monitors (see gdk_screen_get_n_monitors()).
*
* GdkScreen is used throughout GDK and GTK+ to specify which screen
* the top level windows are to be displayed on. it is also used to
* query the screen specification and default settings such as
* the default visual (gdk_screen_get_system_visual()), the dimensions
* of the physical monitors (gdk_screen_get_monitor_geometry()), etc.
*/
static void gdk_screen_finalize (GObject *object);
static void gdk_screen_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec);
static void gdk_screen_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec);
enum
{
PROP_0,
PROP_FONT_OPTIONS,
PROP_RESOLUTION
};
enum
{
SIZE_CHANGED,
COMPOSITED_CHANGED,
MONITORS_CHANGED,
LAST_SIGNAL
};
static guint signals[LAST_SIGNAL] = { 0 };
G_DEFINE_TYPE (GdkScreen, gdk_screen, G_TYPE_OBJECT)
static void
gdk_screen_class_init (GdkScreenClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->finalize = gdk_screen_finalize;
object_class->set_property = gdk_screen_set_property;
object_class->get_property = gdk_screen_get_property;
g_object_class_install_property (object_class,
PROP_FONT_OPTIONS,
g_param_spec_pointer ("font-options",
P_("Font options"),
P_("The default font options for the screen"),
G_PARAM_READWRITE|G_PARAM_STATIC_NAME|
G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
g_object_class_install_property (object_class,
PROP_RESOLUTION,
g_param_spec_double ("resolution",
P_("Font resolution"),
P_("The resolution for fonts on the screen"),
-G_MAXDOUBLE,
G_MAXDOUBLE,
-1.0,
G_PARAM_READWRITE|G_PARAM_STATIC_NAME|
G_PARAM_STATIC_NICK|G_PARAM_STATIC_BLURB));
/**
* GdkScreen::size-changed:
* @screen: the object on which the signal is emitted
*
* The ::size-changed signal is emitted when the pixel width or
* height of a screen changes.
*
* Since: 2.2
*/
signals[SIZE_CHANGED] =
g_signal_new (g_intern_static_string ("size-changed"),
G_OBJECT_CLASS_TYPE (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkScreenClass, size_changed),
NULL, NULL,
g_cclosure_marshal_VOID__VOID,
G_TYPE_NONE,
0);
/**
* GdkScreen::composited-changed:
* @screen: the object on which the signal is emitted
*
* The ::composited-changed signal is emitted when the composited
* status of the screen changes
*
* Since: 2.10
*/
signals[COMPOSITED_CHANGED] =
g_signal_new (g_intern_static_string ("composited-changed"),
G_OBJECT_CLASS_TYPE (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkScreenClass, composited_changed),
NULL, NULL,
g_cclosure_marshal_VOID__VOID,
G_TYPE_NONE,
0);
/**
* GdkScreen::monitors-changed:
* @screen: the object on which the signal is emitted
*
* The ::monitors-changed signal is emitted when the number, size
* or position of the monitors attached to the screen change.
*
* Only for X11 and OS X for now. A future implementation for Win32
* may be a possibility.
*
* Since: 2.14
*/
signals[MONITORS_CHANGED] =
g_signal_new (g_intern_static_string ("monitors-changed"),
G_OBJECT_CLASS_TYPE (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GdkScreenClass, monitors_changed),
NULL, NULL,
g_cclosure_marshal_VOID__VOID,
G_TYPE_NONE,
0);
}
static void
gdk_screen_init (GdkScreen *screen)
{
screen->resolution = -1.;
}
static void
gdk_screen_finalize (GObject *object)
{
GdkScreen *screen = GDK_SCREEN (object);
if (screen->font_options)
cairo_font_options_destroy (screen->font_options);
G_OBJECT_CLASS (gdk_screen_parent_class)->finalize (object);
}
void
_gdk_screen_close (GdkScreen *screen)
{
g_return_if_fail (GDK_IS_SCREEN (screen));
if (!screen->closed)
{
screen->closed = TRUE;
g_object_run_dispose (G_OBJECT (screen));
}
}
/* Fallback used when the monitor "at" a point or window
* doesnt exist.
*/
static gint
get_nearest_monitor (GdkScreen *screen,
gint x,
gint y)
{
gint num_monitors, i;
gint nearest_dist = G_MAXINT;
gint nearest_monitor = 0;
g_return_val_if_fail (GDK_IS_SCREEN (screen), -1);
num_monitors = gdk_screen_get_n_monitors (screen);
for (i = 0; i < num_monitors; i++)
{
GdkRectangle monitor;
gint dist_x, dist_y, dist;
gdk_screen_get_monitor_geometry (screen, i, &monitor);
if (x < monitor.x)
dist_x = monitor.x - x;
else if (x >= monitor.x + monitor.width)
dist_x = x - (monitor.x + monitor.width) + 1;
else
dist_x = 0;
if (y < monitor.y)
dist_y = monitor.y - y;
else if (y >= monitor.y + monitor.height)
dist_y = y - (monitor.y + monitor.height) + 1;
else
dist_y = 0;
dist = dist_x + dist_y;
if (dist < nearest_dist)
{
nearest_dist = dist;
nearest_monitor = i;
}
}
return nearest_monitor;
}
/**
* gdk_screen_get_monitor_at_point:
* @screen: a #GdkScreen.
* @x: the x coordinate in the virtual screen.
* @y: the y coordinate in the virtual screen.
*
* Returns the monitor number in which the point (@x,@y) is located.
*
* Returns: the monitor number in which the point (@x,@y) lies, or
* a monitor close to (@x,@y) if the point is not in any monitor.
*
* Since: 2.2
**/
gint
gdk_screen_get_monitor_at_point (GdkScreen *screen,
gint x,
gint y)
{
gint num_monitors, i;
g_return_val_if_fail (GDK_IS_SCREEN (screen), -1);
num_monitors = gdk_screen_get_n_monitors (screen);
for (i=0;i<num_monitors;i++)
{
GdkRectangle monitor;
gdk_screen_get_monitor_geometry (screen, i, &monitor);
if (x >= monitor.x &&
x < monitor.x + monitor.width &&
y >= monitor.y &&
y < (monitor.y + monitor.height))
return i;
}
return get_nearest_monitor (screen, x, y);
}
/**
* gdk_screen_get_monitor_at_window:
* @screen: a #GdkScreen.
* @window: a #GdkWindow
*
* Returns the number of the monitor in which the largest area of the
* bounding rectangle of @window resides.
*
* Returns: the monitor number in which most of @window is located,
* or if @window does not intersect any monitors, a monitor,
* close to @window.
*
* Since: 2.2
**/
gint
gdk_screen_get_monitor_at_window (GdkScreen *screen,
GdkWindow *window)
{
gint num_monitors, i, area = 0, screen_num = -1;
GdkRectangle win_rect;
g_return_val_if_fail (GDK_IS_SCREEN (screen), -1);
gdk_window_get_geometry (window, &win_rect.x, &win_rect.y, &win_rect.width,
&win_rect.height);
gdk_window_get_origin (window, &win_rect.x, &win_rect.y);
num_monitors = gdk_screen_get_n_monitors (screen);
for (i=0;i<num_monitors;i++)
{
GdkRectangle tmp_monitor, intersect;
gdk_screen_get_monitor_geometry (screen, i, &tmp_monitor);
gdk_rectangle_intersect (&win_rect, &tmp_monitor, &intersect);
if (intersect.width * intersect.height > area)
{
area = intersect.width * intersect.height;
screen_num = i;
}
}
if (screen_num >= 0)
return screen_num;
else
return get_nearest_monitor (screen,
win_rect.x + win_rect.width / 2,
win_rect.y + win_rect.height / 2);
}
/**
* gdk_screen_width:
*
* Returns the width of the default screen in pixels.
*
* Returns: the width of the default screen in pixels.
**/
gint
gdk_screen_width (void)
{
return gdk_screen_get_width (gdk_screen_get_default ());
}
/**
* gdk_screen_height:
*
* Returns the height of the default screen in pixels.
*
* Returns: the height of the default screen in pixels.
**/
gint
gdk_screen_height (void)
{
return gdk_screen_get_height (gdk_screen_get_default ());
}
/**
* gdk_screen_width_mm:
*
* Returns the width of the default screen in millimeters.
* Note that on many X servers this value will not be correct.
*
* Returns: the width of the default screen in millimeters,
* though it is not always correct.
**/
gint
gdk_screen_width_mm (void)
{
return gdk_screen_get_width_mm (gdk_screen_get_default ());
}
/**
* gdk_screen_height_mm:
*
* Returns the height of the default screen in millimeters.
* Note that on many X servers this value will not be correct.
*
* Returns: the height of the default screen in millimeters,
* though it is not always correct.
**/
gint
gdk_screen_height_mm (void)
{
return gdk_screen_get_height_mm (gdk_screen_get_default ());
}
/**
* gdk_screen_set_font_options:
* @screen: a #GdkScreen
* @options: (allow-none): a #cairo_font_options_t, or %NULL to unset any
* previously set default font options.
*
* Sets the default font options for the screen. These
* options will be set on any #PangoContexts newly created
* with gdk_pango_context_get_for_screen(). Changing the
* default set of font options does not affect contexts that
* have already been created.
*
* Since: 2.10
**/
void
gdk_screen_set_font_options (GdkScreen *screen,
const cairo_font_options_t *options)
{
g_return_if_fail (GDK_IS_SCREEN (screen));
if (screen->font_options != options)
{
if (screen->font_options)
cairo_font_options_destroy (screen->font_options);
if (options)
screen->font_options = cairo_font_options_copy (options);
else
screen->font_options = NULL;
g_object_notify (G_OBJECT (screen), "font-options");
}
}
/**
* gdk_screen_get_font_options:
* @screen: a #GdkScreen
*
* Gets any options previously set with gdk_screen_set_font_options().
*
* Returns: the current font options, or %NULL if no default
* font options have been set.
*
* Since: 2.10
**/
const cairo_font_options_t *
gdk_screen_get_font_options (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return screen->font_options;
}
/**
* gdk_screen_set_resolution:
* @screen: a #GdkScreen
* @dpi: the resolution in “dots per inch”. (Physical inches arent actually
* involved; the terminology is conventional.)
* 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).
*
* Since: 2.10
**/
void
gdk_screen_set_resolution (GdkScreen *screen,
gdouble dpi)
{
g_return_if_fail (GDK_IS_SCREEN (screen));
if (dpi < 0)
dpi = -1.0;
if (screen->resolution != dpi)
{
screen->resolution = dpi;
g_object_notify (G_OBJECT (screen), "resolution");
}
}
/**
* gdk_screen_get_resolution:
* @screen: a #GdkScreen
*
* Gets the resolution for font handling on the screen; see
* gdk_screen_set_resolution() for full details.
*
* Returns: the current resolution, or -1 if no resolution
* has been set.
*
* Since: 2.10
**/
gdouble
gdk_screen_get_resolution (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), -1.0);
return screen->resolution;
}
static void
gdk_screen_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GdkScreen *screen = GDK_SCREEN (object);
switch (prop_id)
{
case PROP_FONT_OPTIONS:
g_value_set_pointer (value, (gpointer) gdk_screen_get_font_options (screen));
break;
case PROP_RESOLUTION:
g_value_set_double (value, gdk_screen_get_resolution (screen));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gdk_screen_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GdkScreen *screen = GDK_SCREEN (object);
switch (prop_id)
{
case PROP_FONT_OPTIONS:
gdk_screen_set_font_options (screen, g_value_get_pointer (value));
break;
case PROP_RESOLUTION:
gdk_screen_set_resolution (screen, g_value_get_double (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/**
* gdk_screen_get_display:
* @screen: a #GdkScreen
*
* Gets the display to which the @screen belongs.
*
* Returns: (transfer none): the display to which @screen belongs
*
* Since: 2.2
**/
GdkDisplay *
gdk_screen_get_display (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_display (screen);
}
/**
* gdk_screen_get_width:
* @screen: a #GdkScreen
*
* Gets the width of @screen in pixels
*
* Returns: the width of @screen in pixels.
*
* Since: 2.2
**/
gint
gdk_screen_get_width (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_width (screen);
}
/**
* gdk_screen_get_height:
* @screen: a #GdkScreen
*
* Gets the height of @screen in pixels
*
* Returns: the height of @screen in pixels.
*
* Since: 2.2
**/
gint
gdk_screen_get_height (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_height (screen);
}
/**
* gdk_screen_get_width_mm:
* @screen: a #GdkScreen
*
* Gets the width of @screen in millimeters.
* Note that on some X servers this value will not be correct.
*
* Returns: the width of @screen in millimeters.
*
* Since: 2.2
**/
gint
gdk_screen_get_width_mm (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_width_mm (screen);
}
/**
* gdk_screen_get_height_mm:
* @screen: a #GdkScreen
*
* Returns the height of @screen in millimeters.
* Note that on some X servers this value will not be correct.
*
* Returns: the heigth of @screen in millimeters.
*
* Since: 2.2
**/
gint
gdk_screen_get_height_mm (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_height_mm (screen);
}
/**
* gdk_screen_get_number:
* @screen: a #GdkScreen
*
* Gets the index of @screen among the screens in the display
* to which it belongs. (See gdk_screen_get_display())
*
* Returns: the index
*
* Since: 2.2
**/
gint
gdk_screen_get_number (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_number (screen);
}
/**
* gdk_screen_get_root_window:
* @screen: a #GdkScreen
*
* Gets the root window of @screen.
*
* Returns: (transfer none): the root window
*
* Since: 2.2
**/
GdkWindow *
gdk_screen_get_root_window (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_root_window (screen);
}
/**
* gdk_screen_get_n_monitors:
* @screen: a #GdkScreen
*
* Returns the number of monitors which @screen consists of.
*
* Returns: number of monitors which @screen consists of
*
* Since: 2.2
*/
gint
gdk_screen_get_n_monitors (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_n_monitors (screen);
}
/**
* gdk_screen_get_primary_monitor:
* @screen: a #GdkScreen.
*
* Gets the primary monitor for @screen. The primary monitor
* is considered the monitor where the “main desktop” lives.
* While normal application windows typically allow the window
* manager to place the windows, specialized desktop applications
* such as panels should place themselves on the primary monitor.
*
* If no primary monitor is configured by the user, the return value
* will be 0, defaulting to the first monitor.
*
* Returns: An integer index for the primary monitor, or 0 if none is configured.
*
* Since: 2.20
*/
gint
gdk_screen_get_primary_monitor (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), 0);
return GDK_SCREEN_GET_CLASS (screen)->get_primary_monitor (screen);
}
/**
* gdk_screen_get_monitor_width_mm:
* @screen: a #GdkScreen
* @monitor_num: number of the monitor, between 0 and gdk_screen_get_n_monitors (screen)
*
* Gets the width in millimeters of the specified monitor, if available.
*
* Returns: the width of the monitor, or -1 if not available
*
* Since: 2.14
*/
gint
gdk_screen_get_monitor_width_mm (GdkScreen *screen,
gint monitor_num)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), -1);
g_return_val_if_fail (monitor_num >= 0, -1);
g_return_val_if_fail (monitor_num < gdk_screen_get_n_monitors (screen), -1);
return GDK_SCREEN_GET_CLASS (screen)->get_monitor_width_mm (screen, monitor_num);
}
/**
* gdk_screen_get_monitor_height_mm:
* @screen: a #GdkScreen
* @monitor_num: number of the monitor, between 0 and gdk_screen_get_n_monitors (screen)
*
* Gets the height in millimeters of the specified monitor.
*
* Returns: the height of the monitor, or -1 if not available
*
* Since: 2.14
*/
gint
gdk_screen_get_monitor_height_mm (GdkScreen *screen,
gint monitor_num)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), -1);
g_return_val_if_fail (monitor_num >= 0, -1);
g_return_val_if_fail (monitor_num < gdk_screen_get_n_monitors (screen), -1);
return GDK_SCREEN_GET_CLASS (screen)->get_monitor_height_mm (screen, monitor_num);
}
/**
* gdk_screen_get_monitor_plug_name:
* @screen: a #GdkScreen
* @monitor_num: number of the monitor, between 0 and gdk_screen_get_n_monitors (screen)
*
* Returns the output name of the specified monitor.
* Usually something like VGA, DVI, or TV, not the actual
* product name of the display device.
*
* Returns: a newly-allocated string containing the name of the monitor,
* or %NULL if the name cannot be determined
*
* Since: 2.14
*/
gchar *
gdk_screen_get_monitor_plug_name (GdkScreen *screen,
gint monitor_num)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
g_return_val_if_fail (monitor_num >= 0, NULL);
g_return_val_if_fail (monitor_num < gdk_screen_get_n_monitors (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_monitor_plug_name (screen, monitor_num);
}
/**
* gdk_screen_get_monitor_geometry:
* @screen: a #GdkScreen
* @monitor_num: the monitor number
* @dest: (out) (allow-none): a #GdkRectangle to be filled with
* the monitor geometry
*
* Retrieves the #GdkRectangle representing the size and position of
* the individual monitor within the entire screen area.
*
* Monitor numbers start at 0. To obtain the number of monitors of
* @screen, use gdk_screen_get_n_monitors().
*
* Note that the size of the entire screen area can be retrieved via
* gdk_screen_get_width() and gdk_screen_get_height().
*
* Since: 2.2
*/
void
gdk_screen_get_monitor_geometry (GdkScreen *screen,
gint monitor_num,
GdkRectangle *dest)
{
g_return_if_fail (GDK_IS_SCREEN (screen));
g_return_if_fail (monitor_num >= 0);
g_return_if_fail (monitor_num < gdk_screen_get_n_monitors (screen));
GDK_SCREEN_GET_CLASS(screen)->get_monitor_geometry (screen, monitor_num, dest);
}
/**
* gdk_screen_get_monitor_workarea:
* @screen: a #GdkScreen
* @monitor_num: the monitor number
* @dest: (out) (allow-none): a #GdkRectangle to be filled with
* the monitor workarea
*
* Retrieves the #GdkRectangle representing the size and position of
* the “work area” on a monitor within the entire screen area.
*
* The work area should be considered when positioning menus and
* similar popups, to avoid placing them below panels, docks or other
* desktop components.
*
* Monitor numbers start at 0. To obtain the number of monitors of
* @screen, use gdk_screen_get_n_monitors().
*
* Since: 3.4
*/
void
gdk_screen_get_monitor_workarea (GdkScreen *screen,
gint monitor_num,
GdkRectangle *dest)
{
g_return_if_fail (GDK_IS_SCREEN (screen));
g_return_if_fail (monitor_num >= 0);
g_return_if_fail (monitor_num < gdk_screen_get_n_monitors (screen));
GDK_SCREEN_GET_CLASS (screen)->get_monitor_workarea (screen, monitor_num, dest);
}
/**
* gdk_screen_list_visuals:
* @screen: the relevant #GdkScreen.
*
* Lists the available visuals for the specified @screen.
* A visual describes a hardware image data format.
* For example, a visual might support 24-bit color, or 8-bit color,
* and might expect pixels to be in a certain format.
*
* Call g_list_free() on the return value when youre finished with it.
*
* Returns: (transfer container) (element-type GdkVisual):
* a list of visuals; the list must be freed, but not its contents
*
* Since: 2.2
**/
GList *
gdk_screen_list_visuals (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->list_visuals (screen);
}
/**
* gdk_screen_get_system_visual:
* @screen: a #GdkScreen.
*
* Get the systems default visual for @screen.
* This is the visual for the root window of the display.
* The return value should not be freed.
*
* Returns: (transfer none): the system visual
*
* Since: 2.2
**/
GdkVisual *
gdk_screen_get_system_visual (GdkScreen * screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_system_visual (screen);
}
/**
* gdk_screen_get_rgba_visual:
* @screen: a #GdkScreen
*
* Gets a visual to use for creating windows with an alpha channel.
* The windowing system on which GTK+ is running
* may not support this capability, in which case %NULL will
* be returned. Even if a non-%NULL value is returned, its
* possible that the windows alpha channel wont be honored
* when displaying the window on the screen: in particular, for
* X an appropriate windowing manager and compositing manager
* must be running to provide appropriate display.
*
* This functionality is not implemented in the Windows backend.
*
* For setting an overall opacity for a top-level window, see
* gdk_window_set_opacity().
*
* Returns: (transfer none): a visual to use for windows with an
* alpha channel or %NULL if the capability is not available.
*
* Since: 2.8
**/
GdkVisual *
gdk_screen_get_rgba_visual (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_rgba_visual (screen);
}
/**
* gdk_screen_is_composited:
* @screen: a #GdkScreen
*
* Returns whether windows with an RGBA visual can reasonably
* be expected to have their alpha channel drawn correctly on
* the screen.
*
* On X11 this function returns whether a compositing manager is
* compositing @screen.
*
* Returns: Whether windows with RGBA visuals can reasonably be
* expected to have their alpha channels drawn correctly on the screen.
*
* Since: 2.10
**/
gboolean
gdk_screen_is_composited (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), FALSE);
return GDK_SCREEN_GET_CLASS (screen)->is_composited (screen);
}
/**
* gdk_screen_make_display_name:
* @screen: a #GdkScreen
*
* Determines the name to pass to gdk_display_open() to get
* a #GdkDisplay with this screen as the default screen.
*
* Returns: a newly allocated string, free with g_free()
*
* Since: 2.2
**/
gchar *
gdk_screen_make_display_name (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->make_display_name (screen);
}
/**
* gdk_screen_get_active_window:
* @screen: a #GdkScreen
*
* Returns the screens currently active window.
*
* On X11, this is done by inspecting the _NET_ACTIVE_WINDOW property
* on the root window, as described in the
* [Extended Window Manager Hints](http://www.freedesktop.org/Standards/wm-spec).
* If there is no currently currently active
* window, or the window manager does not support the
* _NET_ACTIVE_WINDOW hint, this function returns %NULL.
*
* On other platforms, this function may return %NULL, depending on whether
* it is implementable on that platform.
*
* The returned window should be unrefed using g_object_unref() when
* no longer needed.
*
* Returns: (transfer full): the currently active window, or %NULL.
*
* Since: 2.10
**/
GdkWindow *
gdk_screen_get_active_window (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_active_window (screen);
}
/**
* gdk_screen_get_window_stack:
* @screen: a #GdkScreen
*
* Returns a #GList of #GdkWindows representing the current
* window stack.
*
* On X11, this is done by inspecting the _NET_CLIENT_LIST_STACKING
* property on the root window, as described in the
* [Extended Window Manager Hints](http://www.freedesktop.org/Standards/wm-spec).
* If the window manager does not support the
* _NET_CLIENT_LIST_STACKING hint, this function returns %NULL.
*
* On other platforms, this function may return %NULL, depending on whether
* it is implementable on that platform.
*
* The returned list is newly allocated and owns references to the
* windows it contains, so it should be freed using g_list_free() and
* its windows unrefed using g_object_unref() when no longer needed.
*
* Returns: (transfer full) (element-type GdkWindow):
* a list of #GdkWindows for the current window stack,
* or %NULL.
*
* Since: 2.10
**/
GList *
gdk_screen_get_window_stack (GdkScreen *screen)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
return GDK_SCREEN_GET_CLASS (screen)->get_window_stack (screen);
}
/**
* gdk_screen_get_setting:
* @screen: the #GdkScreen where the setting is located
* @name: the name of the setting
* @value: location to store the value of the setting
*
* Retrieves a desktop-wide setting such as double-click time
* for the #GdkScreen @screen.
*
* FIXME needs a list of valid settings here, or a link to
* more information.
*
* Returns: %TRUE if the setting existed and a value was stored
* in @value, %FALSE otherwise.
*
* Since: 2.2
**/
gboolean
gdk_screen_get_setting (GdkScreen *screen,
const gchar *name,
GValue *value)
{
g_return_val_if_fail (GDK_IS_SCREEN (screen), FALSE);
g_return_val_if_fail (name != NULL, FALSE);
g_return_val_if_fail (value != NULL, FALSE);
return GDK_SCREEN_GET_CLASS (screen)->get_setting (screen, name, value);
}
/**
* gdk_screen_get_monitor_scale_factor:
* @screen: screen to get scale factor for
* @monitor_num: number of the monitor, between 0 and gdk_screen_get_n_monitors (screen)
*
* Returns the internal scale factor that maps from monitor coordiantes
* to the actual device pixels. On traditional systems this is 1, but
* on very high density outputs this can be a higher value (often 2).
*
* This can be used if you want to create pixel based data for a
* particula monitor, but most of the time youre drawing to a window
* where it is better to use gdk_window_get_scale_factor() instead.
*
* Since: 3.10
* Returns: the scale factor
*/
gint
gdk_screen_get_monitor_scale_factor (GdkScreen *screen,
gint monitor_num)
{
GdkScreenClass *screen_class;
g_return_val_if_fail (GDK_IS_SCREEN (screen), 1);
g_return_val_if_fail (monitor_num >= 0, 1);
g_return_val_if_fail (monitor_num < gdk_screen_get_n_monitors (screen), 1);
screen_class = GDK_SCREEN_GET_CLASS (screen);
if (screen_class->get_monitor_scale_factor)
return screen_class->get_monitor_scale_factor (screen, monitor_num);
return 1;
}