gtk2/gdk/gdkdraw.c
2010-08-10 21:02:28 +02:00

559 lines
16 KiB
C

/* GDK - The GIMP Drawing Kit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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.
*/
/*
* Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GTK+ Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GTK+ at ftp://ftp.gtk.org/pub/gtk/.
*/
#include "config.h"
#include <math.h>
#include <pango/pangocairo.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
#include "gdkcairo.h"
#include "gdkdrawable.h"
#include "gdkinternals.h"
#include "gdkwindow.h"
#include "gdkscreen.h"
#include "gdkpixbuf.h"
static GdkDrawable* gdk_drawable_real_get_composite_drawable (GdkDrawable *drawable,
gint x,
gint y,
gint width,
gint height,
gint *composite_x_offset,
gint *composite_y_offset);
static cairo_region_t * gdk_drawable_real_get_visible_region (GdkDrawable *drawable);
static void gdk_drawable_real_draw_drawable (GdkDrawable *drawable,
GdkGC *gc,
GdkDrawable *src,
gint xsrc,
gint ysrc,
gint xdest,
gint ydest,
gint width,
gint height);
G_DEFINE_ABSTRACT_TYPE (GdkDrawable, gdk_drawable, G_TYPE_OBJECT)
static void
gdk_drawable_class_init (GdkDrawableClass *klass)
{
klass->get_composite_drawable = gdk_drawable_real_get_composite_drawable;
/* Default implementation for clip and visible region is the same */
klass->get_clip_region = gdk_drawable_real_get_visible_region;
klass->get_visible_region = gdk_drawable_real_get_visible_region;
klass->draw_drawable = gdk_drawable_real_draw_drawable;
}
static void
gdk_drawable_init (GdkDrawable *drawable)
{
}
/* Manipulation of drawables
*/
/**
* gdk_drawable_get_size:
* @drawable: a #GdkDrawable
* @width: (out) (allow-none): location to store drawable's width, or %NULL
* @height: (out) (allow-none): location to store drawable's height, or %NULL
*
* Fills *@width and *@height with the size of @drawable.
* @width or @height can be %NULL if you only want the other one.
*
* On the X11 platform, if @drawable is a #GdkWindow, the returned
* size is the size reported in the most-recently-processed configure
* event, rather than the current size on the X server.
*
**/
void
gdk_drawable_get_size (GdkDrawable *drawable,
gint *width,
gint *height)
{
g_return_if_fail (GDK_IS_DRAWABLE (drawable));
GDK_DRAWABLE_GET_CLASS (drawable)->get_size (drawable, width, height);
}
/**
* gdk_drawable_get_visual:
* @drawable: a #GdkDrawable
*
* Gets the #GdkVisual describing the pixel format of @drawable.
*
* Return value: a #GdkVisual
**/
GdkVisual*
gdk_drawable_get_visual (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return GDK_DRAWABLE_GET_CLASS (drawable)->get_visual (drawable);
}
/**
* gdk_drawable_get_depth:
* @drawable: a #GdkDrawable
*
* Obtains the bit depth of the drawable, that is, the number of bits
* that make up a pixel in the drawable's visual. Examples are 8 bits
* per pixel, 24 bits per pixel, etc.
*
* Return value: number of bits per pixel
**/
gint
gdk_drawable_get_depth (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), 0);
return GDK_DRAWABLE_GET_CLASS (drawable)->get_depth (drawable);
}
/**
* gdk_drawable_get_screen:
* @drawable: a #GdkDrawable
*
* Gets the #GdkScreen associated with a #GdkDrawable.
*
* Return value: the #GdkScreen associated with @drawable
*
* Since: 2.2
**/
GdkScreen*
gdk_drawable_get_screen(GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return GDK_DRAWABLE_GET_CLASS (drawable)->get_screen (drawable);
}
/**
* gdk_drawable_get_display:
* @drawable: a #GdkDrawable
*
* Gets the #GdkDisplay associated with a #GdkDrawable.
*
* Return value: the #GdkDisplay associated with @drawable
*
* Since: 2.2
**/
GdkDisplay*
gdk_drawable_get_display (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return gdk_screen_get_display (gdk_drawable_get_screen (drawable));
}
/**
* gdk_drawable_set_colormap:
* @drawable: a #GdkDrawable
* @colormap: a #GdkColormap
*
* Sets the colormap associated with @drawable. Normally this will
* happen automatically when the drawable is created; you only need to
* use this function if the drawable-creating function did not have a
* way to determine the colormap, and you then use drawable operations
* that require a colormap. The colormap for all drawables and
* graphics contexts you intend to use together should match. i.e.
* when using a #GdkGC to draw to a drawable, or copying one drawable
* to another, the colormaps should match.
*
**/
void
gdk_drawable_set_colormap (GdkDrawable *drawable,
GdkColormap *cmap)
{
g_return_if_fail (GDK_IS_DRAWABLE (drawable));
g_return_if_fail (cmap == NULL || gdk_drawable_get_depth (drawable)
== cmap->visual->depth);
GDK_DRAWABLE_GET_CLASS (drawable)->set_colormap (drawable, cmap);
}
/**
* gdk_drawable_get_colormap:
* @drawable: a #GdkDrawable
*
* Gets the colormap for @drawable, if one is set; returns
* %NULL otherwise.
*
* Return value: the colormap, or %NULL
**/
GdkColormap*
gdk_drawable_get_colormap (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return GDK_DRAWABLE_GET_CLASS (drawable)->get_colormap (drawable);
}
/* Drawing
*/
/**
* gdk_draw_drawable:
* @drawable: a #GdkDrawable
* @gc: a #GdkGC sharing the drawable's visual and colormap
* @src: the source #GdkDrawable, which may be the same as @drawable
* @xsrc: X position in @src of rectangle to draw
* @ysrc: Y position in @src of rectangle to draw
* @xdest: X position in @drawable where the rectangle should be drawn
* @ydest: Y position in @drawable where the rectangle should be drawn
* @width: width of rectangle to draw, or -1 for entire @src width
* @height: height of rectangle to draw, or -1 for entire @src height
*
* Copies the @width x @height region of @src at coordinates (@xsrc,
* @ysrc) to coordinates (@xdest, @ydest) in @drawable.
* @width and/or @height may be given as -1, in which case the entire
* @src drawable will be copied.
*
* Most fields in @gc are not used for this operation, but notably the
* clip mask or clip region will be honored.
*
* The source and destination drawables must have the same visual and
* colormap, or errors will result. (On X11, failure to match
* visual/colormap results in a BadMatch error from the X server.)
* A common cause of this problem is an attempt to draw a bitmap to
* a color drawable. The way to draw a bitmap is to set the bitmap as
* the stipple on the #GdkGC, set the fill mode to %GDK_STIPPLED, and
* then draw the rectangle.
**/
void
gdk_draw_drawable (GdkDrawable *drawable,
GdkGC *gc,
GdkDrawable *src,
gint xsrc,
gint ysrc,
gint xdest,
gint ydest,
gint width,
gint height)
{
GdkDrawable *composite;
gint composite_x_offset = 0;
gint composite_y_offset = 0;
g_return_if_fail (GDK_IS_DRAWABLE (drawable));
g_return_if_fail (GDK_IS_DRAWABLE (src));
g_return_if_fail (GDK_IS_GC (gc));
if (width < 0 || height < 0)
{
gint real_width;
gint real_height;
gdk_drawable_get_size (src, &real_width, &real_height);
if (width < 0)
width = real_width;
if (height < 0)
height = real_height;
}
composite =
GDK_DRAWABLE_GET_CLASS (src)->get_composite_drawable (src,
xsrc, ysrc,
width, height,
&composite_x_offset,
&composite_y_offset);
/* TODO: For non-native windows this may copy stuff from other overlapping
windows. We should clip that and (for windows with bg != None) clear that
area in the destination instead. */
if (GDK_DRAWABLE_GET_CLASS (drawable)->draw_drawable_with_src)
GDK_DRAWABLE_GET_CLASS (drawable)->draw_drawable_with_src (drawable, gc,
composite,
xsrc - composite_x_offset,
ysrc - composite_y_offset,
xdest, ydest,
width, height,
src);
else /* backwards compat for old out-of-tree implementations of GdkDrawable (are there any?) */
GDK_DRAWABLE_GET_CLASS (drawable)->draw_drawable (drawable, gc,
composite,
xsrc - composite_x_offset,
ysrc - composite_y_offset,
xdest, ydest,
width, height);
g_object_unref (composite);
}
static GdkDrawable *
gdk_drawable_real_get_composite_drawable (GdkDrawable *drawable,
gint x,
gint y,
gint width,
gint height,
gint *composite_x_offset,
gint *composite_y_offset)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
*composite_x_offset = 0;
*composite_y_offset = 0;
return g_object_ref (drawable);
}
/**
* gdk_drawable_get_clip_region:
* @drawable: a #GdkDrawable
*
* Computes the region of a drawable that potentially can be written
* to by drawing primitives. This region will not take into account
* the clip region for the GC, and may also not take into account
* other factors such as if the window is obscured by other windows,
* but no area outside of this region will be affected by drawing
* primitives.
*
* Returns: a #cairo_region_t. This must be freed with cairo_region_destroy()
* when you are done.
**/
cairo_region_t *
gdk_drawable_get_clip_region (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return GDK_DRAWABLE_GET_CLASS (drawable)->get_clip_region (drawable);
}
/**
* gdk_drawable_get_visible_region:
* @drawable: a #GdkDrawable
*
* Computes the region of a drawable that is potentially visible.
* This does not necessarily take into account if the window is
* obscured by other windows, but no area outside of this region
* is visible.
*
* Returns: a #cairo_region_t. This must be freed with cairo_region_destroy()
* when you are done.
**/
cairo_region_t *
gdk_drawable_get_visible_region (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return GDK_DRAWABLE_GET_CLASS (drawable)->get_visible_region (drawable);
}
static cairo_region_t *
gdk_drawable_real_get_visible_region (GdkDrawable *drawable)
{
GdkRectangle rect;
rect.x = 0;
rect.y = 0;
gdk_drawable_get_size (drawable, &rect.width, &rect.height);
return cairo_region_create_rectangle (&rect);
}
/**
* _gdk_drawable_ref_cairo_surface:
* @drawable: a #GdkDrawable
*
* Obtains a #cairo_surface_t for the given drawable. If a
* #cairo_surface_t for the drawable already exists, it will be
* referenced, otherwise a new surface will be created.
*
* Return value: a newly referenced #cairo_surface_t that points
* to @drawable. Unref with cairo_surface_destroy()
**/
cairo_surface_t *
_gdk_drawable_ref_cairo_surface (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
return GDK_DRAWABLE_GET_CLASS (drawable)->ref_cairo_surface (drawable);
}
/* Implementation of the old vfunc in terms of the new one
in case someone calls it directly (which they shouldn't!) */
static void
gdk_drawable_real_draw_drawable (GdkDrawable *drawable,
GdkGC *gc,
GdkDrawable *src,
gint xsrc,
gint ysrc,
gint xdest,
gint ydest,
gint width,
gint height)
{
GDK_DRAWABLE_GET_CLASS (drawable)->draw_drawable_with_src (drawable,
gc,
src,
xsrc,
ysrc,
xdest,
ydest,
width,
height,
src);
}
/************************************************************************/
/**
* _gdk_drawable_get_scratch_gc:
* @drawable: A #GdkDrawable
* @graphics_exposures: Whether the returned #GdkGC should generate graphics exposures
*
* Returns a #GdkGC suitable for drawing on @drawable. The #GdkGC has
* the standard values for @drawable, except for the graphics_exposures
* field which is determined by the @graphics_exposures parameter.
*
* The foreground color of the returned #GdkGC is undefined. The #GdkGC
* must not be altered in any way, except to change its foreground color.
*
* Return value: A #GdkGC suitable for drawing on @drawable
*
* Since: 2.4
**/
GdkGC *
_gdk_drawable_get_scratch_gc (GdkDrawable *drawable,
gboolean graphics_exposures)
{
GdkScreen *screen;
gint depth;
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
screen = gdk_drawable_get_screen (drawable);
g_return_val_if_fail (!screen->closed, NULL);
depth = gdk_drawable_get_depth (drawable) - 1;
if (graphics_exposures)
{
if (!screen->exposure_gcs[depth])
{
GdkGCValues values;
GdkGCValuesMask mask;
values.graphics_exposures = TRUE;
mask = GDK_GC_EXPOSURES;
screen->exposure_gcs[depth] =
gdk_gc_new_with_values (drawable, &values, mask);
}
return screen->exposure_gcs[depth];
}
else
{
if (!screen->normal_gcs[depth])
{
screen->normal_gcs[depth] =
gdk_gc_new (drawable);
}
return screen->normal_gcs[depth];
}
}
/**
* _gdk_drawable_get_subwindow_scratch_gc:
* @drawable: A #GdkDrawable
*
* Returns a #GdkGC suitable for drawing on @drawable. The #GdkGC has
* the standard values for @drawable, except for the graphics_exposures
* field which is %TRUE and the subwindow mode which is %GDK_INCLUDE_INFERIORS.
*
* The foreground color of the returned #GdkGC is undefined. The #GdkGC
* must not be altered in any way, except to change its foreground color.
*
* Return value: A #GdkGC suitable for drawing on @drawable
*
* Since: 2.18
**/
GdkGC *
_gdk_drawable_get_subwindow_scratch_gc (GdkDrawable *drawable)
{
GdkScreen *screen;
gint depth;
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
screen = gdk_drawable_get_screen (drawable);
g_return_val_if_fail (!screen->closed, NULL);
depth = gdk_drawable_get_depth (drawable) - 1;
if (!screen->subwindow_gcs[depth])
{
GdkGCValues values;
GdkGCValuesMask mask;
values.graphics_exposures = TRUE;
values.subwindow_mode = GDK_INCLUDE_INFERIORS;
mask = GDK_GC_EXPOSURES | GDK_GC_SUBWINDOW;
screen->subwindow_gcs[depth] =
gdk_gc_new_with_values (drawable, &values, mask);
}
return screen->subwindow_gcs[depth];
}
/*
* _gdk_drawable_get_source_drawable:
* @drawable: a #GdkDrawable
*
* Returns a drawable for the passed @drawable that is guaranteed to be
* usable to create a pixmap (e.g.: not an offscreen window).
*
* Since: 2.16
*/
GdkDrawable *
_gdk_drawable_get_source_drawable (GdkDrawable *drawable)
{
g_return_val_if_fail (GDK_IS_DRAWABLE (drawable), NULL);
if (GDK_DRAWABLE_GET_CLASS (drawable)->get_source_drawable)
return GDK_DRAWABLE_GET_CLASS (drawable)->get_source_drawable (drawable);
return drawable;
}
cairo_surface_t *
_gdk_drawable_create_cairo_surface (GdkDrawable *drawable,
int width,
int height)
{
return GDK_DRAWABLE_GET_CLASS (drawable)->create_cairo_surface (drawable,
width, height);
}