blob: ee794baf40a3c4d5f06cd451a30465d5dc360e98 [file] [log] [blame]
/* im_wrap
*
* Copyright: 2008, Nottingham Trent University
* Author: Tom Vajzovic
* Written on: 2008-01-15
* 2/2/10
* - rewritten in terms of im_replicate()/im_extract_area()
* - gtkdoc
* - allows any x/y
*/
/*
This file is part of VIPS.
VIPS 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 program 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 program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#include <vips/vips.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
/**
* im_wrap:
* @in: input image
* @out: output image
* @x: horizontal displacement
* @y: vertical displacement
*
* Slice an image up and move the segments about so that the pixel that was
* at 0, 0 is now at @x, @y.
*
* See also: im_embed(), im_replicate(), im_rotquad().
*
* Returns: 0 on success, -1 on error
*/
int
im_wrap( IMAGE *in, IMAGE *out, int x, int y )
{
IMAGE *t;
/* Clock arithmetic: we want negative x/y to wrap around
* nicely.
*/
x = x < 0 ? -x % in->Xsize : in->Xsize - x % in->Xsize;
y = y < 0 ? -y % in->Ysize : in->Ysize - y % in->Ysize;
if( !(t = im_open_local( out, "im_wrap", "p" )) ||
im_replicate( in, t, 2, 2 ) ||
im_extract_area( t, out, x, y, in->Xsize, in->Ysize ) )
return( -1 );
out->Xoffset = x;
out->Yoffset = y;
return( 0 );
}