PIKApp/libpikabase/pikarectangle.c

138 lines
4.3 KiB
C

/* LIBPIKA - The PIKA Library
* Copyright (C) 1995-1997 Spencer Kimball and Peter Mattis
*
* pikarectangle.c
*
* 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 3 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, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <glib.h>
#include "pikarectangle.h"
/**
* SECTION: pikarectangle
* @title: pikarectangle
* @short_description: Utility functions dealing with rectangle extents.
*
* Utility functions dealing with rectangle extents.
**/
/**
* pika_rectangle_intersect:
* @x1: origin of first rectangle
* @y1: origin of first rectangle
* @width1: width of first rectangle
* @height1: height of first rectangle
* @x2: origin of second rectangle
* @y2: origin of second rectangle
* @width2: width of second rectangle
* @height2: height of second rectangle
* @dest_x: (out) (optional): return location for origin of intersection,
* or %NULL
* @dest_y: (out) (optional): return location for origin of intersection,
* or %NULL
* @dest_width: (out) (optional): return location for width of intersection,
* or %NULL
* @dest_height: (out) (optional): return location for height of intersection,
* or %NULL
*
* Calculates the intersection of two rectangles.
*
* Returns: %TRUE if the intersection is non-empty, %FALSE otherwise
*
* Since: 2.4
**/
gboolean
pika_rectangle_intersect (gint x1,
gint y1,
gint width1,
gint height1,
gint x2,
gint y2,
gint width2,
gint height2,
gint *dest_x,
gint *dest_y,
gint *dest_width,
gint *dest_height)
{
gint d_x, d_y;
gint d_w, d_h;
d_x = MAX (x1, x2);
d_y = MAX (y1, y2);
d_w = MIN (x1 + width1, x2 + width2) - d_x;
d_h = MIN (y1 + height1, y2 + height2) - d_y;
if (dest_x) *dest_x = d_x;
if (dest_y) *dest_y = d_y;
if (dest_width) *dest_width = d_w;
if (dest_height) *dest_height = d_h;
return (d_w > 0 && d_h > 0);
}
/**
* pika_rectangle_union:
* @x1: origin of first rectangle
* @y1: origin of first rectangle
* @width1: width of first rectangle
* @height1: height of first rectangle
* @x2: origin of second rectangle
* @y2: origin of second rectangle
* @width2: width of second rectangle
* @height2: height of second rectangle
* @dest_x: (out) (optional): return location for origin of union, or %NULL
* @dest_y: (out) (optional): return location for origin of union, or %NULL
* @dest_width: (out) (optional): return location for width of union, or %NULL
* @dest_height: (out) (optional): return location for height of union, or %NULL
*
* Calculates the union of two rectangles.
*
* Since: 2.8
**/
void
pika_rectangle_union (gint x1,
gint y1,
gint width1,
gint height1,
gint x2,
gint y2,
gint width2,
gint height2,
gint *dest_x,
gint *dest_y,
gint *dest_width,
gint *dest_height)
{
gint d_x, d_y;
gint d_w, d_h;
d_x = MIN (x1, x2);
d_y = MIN (y1, y2);
d_w = MAX (x1 + width1, x2 + width2) - d_x;
d_h = MAX (y1 + height1, y2 + height2) - d_y;
if (dest_x) *dest_x = d_x;
if (dest_y) *dest_y = d_y;
if (dest_width) *dest_width = d_w;
if (dest_height) *dest_height = d_h;
}