gtk/gdk/gdkvisual.c
Matthias Clasen c6a5074295 Move GdkVisual parallel-implementable
It turned out no vfuncs were necessary. I've decided to move
the screen member up to GdkVisual, since it is the same in all
backends. The X11 backend subclasses now, to add the X members
that it needs to keep track of. GdkVisual and GdkVisualClass
are hidden now.
2010-12-21 12:06:56 -05:00

468 lines
13 KiB
C

/* 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include "gdkinternals.h"
#include "gdkvisual.h"
#include "gdkscreen.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.
*
* 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.
*
* Return value: (transfer container) (element-type GdkVisual):
* a list of visuals; the list must be freed, but not its contents
**/
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.
*
* Return value: (transfer none): system visual
**/
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.
*
* Return value: best available depth
**/
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.
*
* Return value: best visual type
**/
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.
*
* Return value: (transfer none): best 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.
*
* Return value: (transfer none): best visual for the given depth
**/
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.
*
* Return value: (transfer none): best visual of the given type
**/
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().
*
* Return value: (transfer none): best visual with both @depth and
* @visual_type, or %NULL if none
**/
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): return location for available depths
* @count: (out): 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.
*
**/
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: 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.
**/
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).
*
* Return value: 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.
*
* Return value: 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.
*
* Return value: A #GdkByteOrder stating the byte order of @visual.
*
* Since: 2.22
*/
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.
*
* Return value: The size of a colormap that is suitable for @visual.
*
* Since: 2.22
*/
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.
*
* Return value: The number of significant bits per color value for @visual.
*
* Since: 2.22
*/
gint
gdk_visual_get_bits_per_rgb (GdkVisual *visual)
{
g_return_val_if_fail (GDK_IS_VISUAL (visual), 0);
return visual->bits_per_rgb;
}
/**
* 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));
if (mask)
*mask = visual->red_mask;
if (shift)
*shift = visual->red_shift;
if (precision)
*precision = visual->red_prec;
}
/**
* 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));
if (mask)
*mask = visual->green_mask;
if (shift)
*shift = visual->green_shift;
if (precision)
*precision = visual->green_prec;
}
/**
* 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));
if (mask)
*mask = visual->blue_mask;
if (shift)
*shift = visual->blue_shift;
if (precision)
*precision = visual->blue_prec;
}
/**
* gdk_visual_get_screen:
* @visual: a #GdkVisual
*
* Gets the screen to which this visual belongs
*
* Return value: (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;
}