mirror of
https://github.com/python-pillow/Pillow.git
synced 2024-11-11 04:07:21 +03:00
62 lines
1.2 KiB
C
62 lines
1.2 KiB
C
|
/*
|
||
|
|
* The Python Imaging Library
|
||
|
|
* $Id$
|
||
|
|
*
|
||
|
|
* offset an image in x and y directions
|
||
|
|
*
|
||
|
|
* history:
|
||
|
|
* 96-07-22 fl: Created
|
||
|
|
* 98-11-01 cgw@pgt.com: Fixed negative-array index bug
|
||
|
|
*
|
||
|
|
* Copyright (c) Fredrik Lundh 1996.
|
||
|
|
* Copyright (c) Secret Labs AB 1997.
|
||
|
|
*
|
||
|
|
* See the README file for information on usage and redistribution.
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
#include "Imaging.h"
|
||
|
|
|
||
|
|
|
||
|
|
Imaging
|
||
|
|
ImagingOffset(Imaging im, int xoffset, int yoffset)
|
||
|
|
{
|
||
|
|
int x, y;
|
||
|
|
Imaging imOut;
|
||
|
|
|
||
|
|
if (!im)
|
||
|
|
return (Imaging) ImagingError_ModeError();
|
||
|
|
|
||
|
|
imOut = ImagingNew(im->mode, im->xsize, im->ysize);
|
||
|
|
if (!imOut)
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
ImagingCopyInfo(imOut, im);
|
||
|
|
|
||
|
|
/* make offsets positive to avoid negative coordinates */
|
||
|
|
xoffset %= im->xsize;
|
||
|
|
xoffset = im->xsize - xoffset;
|
||
|
|
if (xoffset < 0)
|
||
|
|
xoffset += im->xsize;
|
||
|
|
|
||
|
|
yoffset %= im->ysize;
|
||
|
|
yoffset = im->ysize - yoffset;
|
||
|
|
if (yoffset < 0)
|
||
|
|
yoffset += im->ysize;
|
||
|
|
|
||
|
|
#define OFFSET(image)\
|
||
|
|
for (y = 0; y < im->ysize; y++)\
|
||
|
|
for (x = 0; x < im->xsize; x++) {\
|
||
|
|
int yi = (y + yoffset) % im->ysize;\
|
||
|
|
int xi = (x + xoffset) % im->xsize;\
|
||
|
|
imOut->image[y][x] = im->image[yi][xi];\
|
||
|
|
}
|
||
|
|
|
||
|
|
if (im->image8)
|
||
|
|
OFFSET(image8)
|
||
|
|
else
|
||
|
|
OFFSET(image32)
|
||
|
|
|
||
|
|
return imOut;
|
||
|
|
}
|