* 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 Library General Public
+ * 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
- * Library General Public License for more details.
+ * Lesser 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.
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
/*
- * Modified by the GTK+ Team and others 1997-1999. See the AUTHORS
+ * 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 <gdk/gdk.h>
+#include "config.h"
+#include "gdkrectangle.h"
+
+
+/**
+ * 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.
+ */
+
+
+/**
+ * gdk_rectangle_union:
+ * @src1: a #GdkRectangle
+ * @src2: a #GdkRectangle
+ * @dest: (out): 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.
+ * It is allowed for @dest to be the same as either @src1 or @src2.
+ */
void
-gdk_rectangle_union (GdkRectangle *src1,
- GdkRectangle *src2,
- GdkRectangle *dest)
+gdk_rectangle_union (const GdkRectangle *src1,
+ const GdkRectangle *src2,
+ GdkRectangle *dest)
{
+ gint dest_x, dest_y;
+
g_return_if_fail (src1 != NULL);
g_return_if_fail (src2 != NULL);
g_return_if_fail (dest != NULL);
- 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 = 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;
}
-gint
-gdk_rectangle_intersect (GdkRectangle *src1,
- GdkRectangle *src2,
- GdkRectangle *dest)
+/**
+ * gdk_rectangle_intersect:
+ * @src1: a #GdkRectangle
+ * @src2: a #GdkRectangle
+ * @dest: (out caller-allocates) (allow-none): return location for the
+ * intersection of @src1 and @src2, or %NULL
+ *
+ * Calculates the intersection of two rectangles. It is allowed for
+ * @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.
+ *
+ * Returns: %TRUE if the rectangles intersect.
+ */
+gboolean
+gdk_rectangle_intersect (const GdkRectangle *src1,
+ const GdkRectangle *src2,
+ GdkRectangle *dest)
{
- GdkRectangle *temp;
- gint src1_x2, src1_y2;
- gint src2_x2, src2_y2;
+ gint dest_x, dest_y;
+ gint dest_x2, dest_y2;
gint return_val;
g_return_val_if_fail (src1 != NULL, FALSE);
g_return_val_if_fail (src2 != NULL, FALSE);
- g_return_val_if_fail (dest != NULL, FALSE);
return_val = FALSE;
- if (src2->x < src1->x)
+ dest_x = MAX (src1->x, src2->x);
+ dest_y = MAX (src1->y, src2->y);
+ dest_x2 = MIN (src1->x + src1->width, src2->x + src2->width);
+ dest_y2 = MIN (src1->y + src1->height, src2->y + src2->height);
+
+ if (dest_x2 > dest_x && dest_y2 > dest_y)
{
- temp = src1;
- src1 = src2;
- src2 = temp;
+ if (dest)
+ {
+ dest->x = dest_x;
+ dest->y = dest_y;
+ dest->width = dest_x2 - dest_x;
+ dest->height = dest_y2 - dest_y;
+ }
+ return_val = TRUE;
}
- dest->x = src2->x;
-
- src1_x2 = src1->x + src1->width;
- src2_x2 = src2->x + src2->width;
-
- if (src2->x < src1_x2)
+ else if (dest)
{
- if (src1_x2 < src2_x2)
- dest->width = src1_x2 - dest->x;
- else
- dest->width = src2_x2 - dest->x;
-
- if (src2->y < src1->y)
- {
- temp = src1;
- src1 = src2;
- src2 = temp;
- }
- dest->y = src2->y;
-
- src1_y2 = src1->y + src1->height;
- src2_y2 = src2->y + src2->height;
-
- if (src2->y < src1_y2)
- {
- return_val = TRUE;
-
- if (src1_y2 < src2_y2)
- dest->height = src1_y2 - dest->y;
- else
- dest->height = src2_y2 - dest->y;
-
- if (dest->height == 0)
- return_val = FALSE;
- if (dest->width == 0)
- return_val = FALSE;
- }
+ dest->width = 0;
+ dest->height = 0;
}
return return_val;
}
+
+static GdkRectangle *
+gdk_rectangle_copy (const GdkRectangle *rectangle)
+{
+ GdkRectangle *result = g_new (GdkRectangle, 1);
+ *result = *rectangle;
+
+ return result;
+}
+
+G_DEFINE_BOXED_TYPE (GdkRectangle, gdk_rectangle,
+ gdk_rectangle_copy,
+ g_free)
projects / ~andy / gtk / blobdiff