GitLab repository storage has been migrated to hashed layout. Please contact Infrastructure team if you notice any issues with repositories or hooks.

gdkrectangle.c 4.47 KB
Newer Older
Cody Russell's avatar
Cody Russell committed
1
/* GDK - The GIMP Drawing Kit
Elliot Lee's avatar
Elliot Lee committed
2 3 4
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
5
 * modify it under the terms of the GNU Lesser General Public
Elliot Lee's avatar
Elliot Lee committed
6 7 8 9 10 11
 * 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
12
 * Lesser General Public License for more details.
Elliot Lee's avatar
Elliot Lee committed
13
 *
14
 * You should have received a copy of the GNU Lesser General Public
15 16 17
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
Elliot Lee's avatar
Elliot Lee committed
18
 */
19 20

/*
21
 * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
22 23 24 25 26
 * 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/. 
 */

27
#include "config.h"
28
#include <gdk/gdk.h>
29

Elliot Lee's avatar
Elliot Lee committed
30

31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
/**
 * SECTION:regions
 * @Short_description: Simple graphical data types
 * @Title: Points and Rectangles
 *
 * GDK provides the #GdkPoint and #GdkRectangle data types for representing pixels
 * and sets of pixels on the screen. Together with Cairo's #cairo_region_t data
 * type, they make up the central types for representing graphical data.
 *
 * #GdkPoint is a simple structure containing an x and y coordinate of a point.
 *
 * #GdkRectangle is a structure holding the position and size of a rectangle.
 * The intersection of two rectangles can be computed with
 * gdk_rectangle_intersect(). To find the union of two rectangles use
 * gdk_rectangle_union().
 *
 * #cairo_region_t is usually used for managing clipping of graphical operations.
 */


Matthias Clasen's avatar
Matthias Clasen committed
51 52 53 54 55 56 57 58 59
/**
 * gdk_rectangle_union:
 * @src1: a #GdkRectangle
 * @src2: a #GdkRectangle
 * @dest: return location for the union of @src1 and @src2
 *
 * Calculates the union of two rectangles.
 * The union of rectangles @src1 and @src2 is the smallest rectangle which
 * includes both @src1 and @src2 within it.
60
 * It is allowed for @dest to be the same as either @src1 or @src2.
Matthias Clasen's avatar
Matthias Clasen committed
61
 */
62
void
63 64 65
gdk_rectangle_union (const GdkRectangle *src1,
		     const GdkRectangle *src2,
		     GdkRectangle       *dest)
66
{
67 68
  gint dest_x, dest_y;
  
69 70 71 72
  g_return_if_fail (src1 != NULL);
  g_return_if_fail (src2 != NULL);
  g_return_if_fail (dest != NULL);

73 74 75 76 77 78
  dest_x = MIN (src1->x, src2->x);
  dest_y = MIN (src1->y, src2->y);
  dest->width = MAX (src1->x + src1->width, src2->x + src2->width) - dest_x;
  dest->height = MAX (src1->y + src1->height, src2->y + src2->height) - dest_y;
  dest->x = dest_x;
  dest->y = dest_y;
79 80
}

Matthias Clasen's avatar
Matthias Clasen committed
81 82 83 84
/**
 * gdk_rectangle_intersect:
 * @src1: a #GdkRectangle
 * @src2: a #GdkRectangle
85 86
 * @dest: (out caller-allocates) (allow-none): return location for the
 * intersection of @src1 and @src2, or %NULL
Matthias Clasen's avatar
Matthias Clasen committed
87
 *
88
 * Calculates the intersection of two rectangles. It is allowed for
89 90 91 92 93
 * @dest to be the same as either @src1 or @src2. If the rectangles 
 * do not intersect, @dest's width and height is set to 0 and its x 
 * and y values are undefined. If you are only interested in whether
 * the rectangles intersect, but not in the intersecting area itself,
 * pass %NULL for @dest.
Matthias Clasen's avatar
Matthias Clasen committed
94 95 96
 *
 * Returns: %TRUE if the rectangles intersect.
 */
Owen Taylor's avatar
Owen Taylor committed
97
gboolean
98 99 100
gdk_rectangle_intersect (const GdkRectangle *src1,
			 const GdkRectangle *src2,
			 GdkRectangle       *dest)
Elliot Lee's avatar
Elliot Lee committed
101
{
102
  gint dest_x, dest_y;
103
  gint dest_x2, dest_y2;
Elliot Lee's avatar
Elliot Lee committed
104 105 106 107 108 109 110
  gint return_val;

  g_return_val_if_fail (src1 != NULL, FALSE);
  g_return_val_if_fail (src2 != NULL, FALSE);

  return_val = FALSE;

111 112
  dest_x = MAX (src1->x, src2->x);
  dest_y = MAX (src1->y, src2->y);
113 114
  dest_x2 = MIN (src1->x + src1->width, src2->x + src2->width);
  dest_y2 = MIN (src1->y + src1->height, src2->y + src2->height);
Elliot Lee's avatar
Elliot Lee committed
115

116
  if (dest_x2 > dest_x && dest_y2 > dest_y)
Elliot Lee's avatar
Elliot Lee committed
117
    {
118 119 120 121
      if (dest)
        {
          dest->x = dest_x;
          dest->y = dest_y;
122 123
          dest->width = dest_x2 - dest_x;
          dest->height = dest_y2 - dest_y;
124
        }
125
      return_val = TRUE;
Elliot Lee's avatar
Elliot Lee committed
126
    }
127
  else if (dest)
128 129 130 131 132
    {
      dest->width = 0;
      dest->height = 0;
    }

Elliot Lee's avatar
Elliot Lee committed
133 134
  return return_val;
}
Owen Taylor's avatar
Owen Taylor committed
135 136 137 138 139 140 141 142 143 144

static GdkRectangle *
gdk_rectangle_copy (const GdkRectangle *rectangle)
{
  GdkRectangle *result = g_new (GdkRectangle, 1);
  *result = *rectangle;

  return result;
}

Christian Persch's avatar
Christian Persch committed
145 146 147
G_DEFINE_BOXED_TYPE (GdkRectangle, gdk_rectangle,
                     gdk_rectangle_copy,
                     g_free)