/* GDK - The GIMP Drawing Kit
* gdkvisual.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 "gdkvisualprivate.h"
#include "gdkscreenprivate.h"
/**
* SECTION:visuals
* @Short_description: Low-level display hardware information
* @Title: Visuals
*
* A #GdkVisual describes a particular video hardware display format.
* It includes information about the number of bits used for each color,
* the way the bits are translated into an RGB value for display, and
* the way the bits are stored in memory. For example, a piece of display
* hardware might support 24-bit color, 16-bit color, or 8-bit color;
* meaning 24/16/8-bit pixel sizes. For a given pixel size, pixels can
* be in different formats; for example the “red” element of an RGB pixel
* may be in the top 8 bits of the pixel, or may be in the lower 4 bits.
*
* There are several standard visuals. The visual returned by
* gdk_screen_get_system_visual() is the system’s default visual, and
* the visual returned by gdk_screen_get_rgba_visual() should be used for
* creating windows with an alpha channel.
*
* A number of functions are provided for determining the “best” available
* visual. For the purposes of making this determination, higher bit depths
* are considered better, and for visuals of the same bit depth,
* %GDK_VISUAL_PSEUDO_COLOR is preferred at 8bpp, otherwise, the visual
* types are ranked in the order of(highest to lowest)
* %GDK_VISUAL_DIRECT_COLOR, %GDK_VISUAL_TRUE_COLOR,
* %GDK_VISUAL_PSEUDO_COLOR, %GDK_VISUAL_STATIC_COLOR,
* %GDK_VISUAL_GRAYSCALE, then %GDK_VISUAL_STATIC_GRAY.
*/
G_DEFINE_TYPE (GdkVisual, gdk_visual, G_TYPE_OBJECT)
static void
gdk_visual_init (GdkVisual *visual)
{
}
static void
gdk_visual_finalize (GObject *object)
{
G_OBJECT_CLASS (gdk_visual_parent_class)->finalize (object);
}
static void
gdk_visual_class_init (GdkVisualClass *visual_class)
{
GObjectClass *object_class = G_OBJECT_CLASS (visual_class);
object_class->finalize = gdk_visual_finalize;
}
/**
* gdk_list_visuals:
*
* Lists the available visuals for the default screen.
* (See gdk_screen_list_visuals())
* 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 you’re finished with it.
*
* Returns: (transfer container) (element-type GdkVisual):
* a list of visuals; the list must be freed, but not its contents
*
* Deprecated: 3.22: Use gdk_screen_list_visuals (gdk_screen_get_default ()).
*/
GList*
gdk_list_visuals (void)
{
return gdk_screen_list_visuals (gdk_screen_get_default ());
}
/**
* gdk_visual_get_system:
*
* Get the system’s default visual for the default GDK screen.
* This is the visual for the root window of the display.
* The return value should not be freed.
*
* Returns: (transfer none): system visual
*
* Deprecated: 3.22: Use gdk_screen_get_system_visual (gdk_screen_get_default ()).
*/
GdkVisual*
gdk_visual_get_system (void)
{
return gdk_screen_get_system_visual (gdk_screen_get_default());
}
/**
* gdk_visual_get_best_depth:
*
* Get the best available depth for the default GDK screen. “Best”
* means “largest,” i.e. 32 preferred over 24 preferred over 8 bits
* per pixel.
*
* Returns: best available depth
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
gint
gdk_visual_get_best_depth (void)
{
GdkScreen *screen = gdk_screen_get_default();
return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_depth (screen);
}
/**
* gdk_visual_get_best_type:
*
* Return the best available visual type for the default GDK screen.
*
* Returns: best visual type
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
GdkVisualType
gdk_visual_get_best_type (void)
{
GdkScreen *screen = gdk_screen_get_default();
return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_type (screen);
}
/**
* gdk_visual_get_best:
*
* Get the visual with the most available colors for the default
* GDK screen. The return value should not be freed.
*
* Returns: (transfer none): best visual
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
GdkVisual*
gdk_visual_get_best (void)
{
GdkScreen *screen = gdk_screen_get_default();
return GDK_SCREEN_GET_CLASS(screen)->visual_get_best (screen);
}
/**
* gdk_visual_get_best_with_depth:
* @depth: a bit depth
*
* Get the best visual with depth @depth for the default GDK screen.
* Color visuals and visuals with mutable colormaps are preferred
* over grayscale or fixed-colormap visuals. The return value should
* not be freed. %NULL may be returned if no visual supports @depth.
*
* Returns: (transfer none): best visual for the given depth
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
GdkVisual*
gdk_visual_get_best_with_depth (gint depth)
{
GdkScreen *screen = gdk_screen_get_default();
return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_with_depth (screen, depth);
}
/**
* gdk_visual_get_best_with_type:
* @visual_type: a visual type
*
* Get the best visual of the given @visual_type for the default GDK screen.
* Visuals with higher color depths are considered better. The return value
* should not be freed. %NULL may be returned if no visual has type
* @visual_type.
*
* Returns: (transfer none): best visual of the given type
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
GdkVisual*
gdk_visual_get_best_with_type (GdkVisualType visual_type)
{
GdkScreen *screen = gdk_screen_get_default();
return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_with_type (screen,
visual_type);
}
/**
* gdk_visual_get_best_with_both:
* @depth: a bit depth
* @visual_type: a visual type
*
* Combines gdk_visual_get_best_with_depth() and
* gdk_visual_get_best_with_type().
*
* Returns: (nullable) (transfer none): best visual with both @depth
* and @visual_type, or %NULL if none
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
GdkVisual*
gdk_visual_get_best_with_both (gint depth,
GdkVisualType visual_type)
{
GdkScreen *screen = gdk_screen_get_default();
return GDK_SCREEN_GET_CLASS(screen)->visual_get_best_with_both (screen, depth, visual_type);
}
/**
* gdk_query_depths:
* @depths: (out) (array length=count) (transfer none): return
* location for available depths
* @count: return location for number of available depths
*
* This function returns the available bit depths for the default
* screen. It’s equivalent to listing the visuals
* (gdk_list_visuals()) and then looking at the depth field in each
* visual, removing duplicates.
*
* The array returned by this function should not be freed.
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
void
gdk_query_depths (gint **depths,
gint *count)
{
GdkScreen *screen = gdk_screen_get_default();
GDK_SCREEN_GET_CLASS(screen)->query_depths (screen, depths, count);
}
/**
* gdk_query_visual_types:
* @visual_types: (out) (array length=count) (transfer none): return
* location for the available visual types
* @count: return location for the number of available visual types
*
* This function returns the available visual types for the default
* screen. It’s equivalent to listing the visuals
* (gdk_list_visuals()) and then looking at the type field in each
* visual, removing duplicates.
*
* The array returned by this function should not be freed.
*
* Deprecated: 3.22: Visual selection should be done using
* gdk_screen_get_system_visual() and gdk_screen_get_rgba_visual()
*/
void
gdk_query_visual_types (GdkVisualType **visual_types,
gint *count)
{
GdkScreen *screen = gdk_screen_get_default();
GDK_SCREEN_GET_CLASS(screen)->query_visual_types (screen, visual_types, count);
}
/**
* gdk_visual_get_visual_type:
* @visual: A #GdkVisual.
*
* Returns the type of visual this is (PseudoColor, TrueColor, etc).
*
* Returns: A #GdkVisualType stating the type of @visual.
*
* Since: 2.22
*/
GdkVisualType
gdk_visual_get_visual_type (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), 0);
return visual->type;
}
/**
* gdk_visual_get_depth:
* @visual: A #GdkVisual.
*
* Returns the bit depth of this visual.
*
* Returns: The bit depth of this visual.
*
* Since: 2.22
*/
gint
gdk_visual_get_depth (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), 0);
return visual->depth;
}
/**
* gdk_visual_get_byte_order:
* @visual: A #GdkVisual.
*
* Returns the byte order of this visual.
*
* The information returned by this function is only relevant
* when working with XImages, and not all backends return
* meaningful information for this.
*
* Returns: A #GdkByteOrder stating the byte order of @visual.
*
* Since: 2.22
*
* Deprecated: 3.22: This information is not useful
*/
GdkByteOrder
gdk_visual_get_byte_order (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), 0);
return visual->byte_order;
}
/**
* gdk_visual_get_colormap_size:
* @visual: A #GdkVisual.
*
* Returns the size of a colormap for this visual.
*
* You have to use platform-specific APIs to manipulate colormaps.
*
* Returns: The size of a colormap that is suitable for @visual.
*
* Since: 2.22
*
* Deprecated: 3.22: This information is not useful, since GDK does not
* provide APIs to operate on colormaps.
*/
gint
gdk_visual_get_colormap_size (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), 0);
return visual->colormap_size;
}
/**
* gdk_visual_get_bits_per_rgb:
* @visual: a #GdkVisual
*
* Returns the number of significant bits per red, green and blue value.
*
* Not all GDK backend provide a meaningful value for this function.
*
* Returns: The number of significant bits per color value for @visual.
*
* Since: 2.22
*
* Deprecated: 3.22. Use gdk_visual_get_red_pixel_details() and its variants to
* learn about the pixel layout of TrueColor and DirectColor visuals
*/
gint
gdk_visual_get_bits_per_rgb (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), 0);
return visual->bits_per_rgb;
}
static void
gdk_visual_get_pixel_details (GdkVisual *visual,
gulong pixel_mask,
guint32 *mask,
gint *shift,
gint *precision)
{
gulong m = 0;
gint s = 0;
gint p = 0;
if (pixel_mask != 0)
{
m = pixel_mask;
while (!(m & 0x1))
{
s++;
m >>= 1;
}
while (m & 0x1)
{
p++;
m >>= 1;
}
}
if (mask)
*mask = pixel_mask;
if (shift)
*shift = s;
if (precision)
*precision = p;
}
/**
* gdk_visual_get_red_pixel_details:
* @visual: A #GdkVisual
* @mask: (out) (allow-none): A pointer to a #guint32 to be filled in, or %NULL
* @shift: (out) (allow-none): A pointer to a #gint to be filled in, or %NULL
* @precision: (out) (allow-none): A pointer to a #gint to be filled in, or %NULL
*
* Obtains values that are needed to calculate red pixel values in TrueColor
* and DirectColor. The “mask” is the significant bits within the pixel.
* The “shift” is the number of bits left we must shift a primary for it
* to be in position (according to the "mask"). Finally, "precision" refers
* to how much precision the pixel value contains for a particular primary.
*
* Since: 2.22
*/
void
gdk_visual_get_red_pixel_details (GdkVisual *visual,
guint32 *mask,
gint *shift,
gint *precision)
{
g_return_if_fail (GDK_IS_VISUAL (visual));
gdk_visual_get_pixel_details (visual, visual->red_mask, mask, shift, precision);
}
/**
* gdk_visual_get_green_pixel_details:
* @visual: a #GdkVisual
* @mask: (out) (allow-none): A pointer to a #guint32 to be filled in, or %NULL
* @shift: (out) (allow-none): A pointer to a #gint to be filled in, or %NULL
* @precision: (out) (allow-none): A pointer to a #gint to be filled in, or %NULL
*
* Obtains values that are needed to calculate green pixel values in TrueColor
* and DirectColor. The “mask” is the significant bits within the pixel.
* The “shift” is the number of bits left we must shift a primary for it
* to be in position (according to the "mask"). Finally, "precision" refers
* to how much precision the pixel value contains for a particular primary.
*
* Since: 2.22
*/
void
gdk_visual_get_green_pixel_details (GdkVisual *visual,
guint32 *mask,
gint *shift,
gint *precision)
{
g_return_if_fail (GDK_IS_VISUAL (visual));
gdk_visual_get_pixel_details (visual, visual->green_mask, mask, shift, precision);
}
/**
* gdk_visual_get_blue_pixel_details:
* @visual: a #GdkVisual
* @mask: (out) (allow-none): A pointer to a #guint32 to be filled in, or %NULL
* @shift: (out) (allow-none): A pointer to a #gint to be filled in, or %NULL
* @precision: (out) (allow-none): A pointer to a #gint to be filled in, or %NULL
*
* Obtains values that are needed to calculate blue pixel values in TrueColor
* and DirectColor. The “mask” is the significant bits within the pixel.
* The “shift” is the number of bits left we must shift a primary for it
* to be in position (according to the "mask"). Finally, "precision" refers
* to how much precision the pixel value contains for a particular primary.
*
* Since: 2.22
*/
void
gdk_visual_get_blue_pixel_details (GdkVisual *visual,
guint32 *mask,
gint *shift,
gint *precision)
{
g_return_if_fail (GDK_IS_VISUAL (visual));
gdk_visual_get_pixel_details (visual, visual->blue_mask, mask, shift, precision);
}
/**
* gdk_visual_get_screen:
* @visual: a #GdkVisual
*
* Gets the screen to which this visual belongs
*
* Returns: (transfer none): the screen to which this visual belongs.
*
* Since: 2.2
*/
GdkScreen *
gdk_visual_get_screen (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), NULL);
return visual->screen;
}