libvips/libvips/inplace/draw.c
2011-12-31 18:22:42 +00:00

102 lines
2.1 KiB
C

/* base class for drawing operations
*
* 27/9/10
* - from im_draw_circle()
* 17/11/10
* - oops, scanline clipping was off by 1
*/
/*
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 <string.h>
#include <vips/vips.h>
#include "draw.h"
/* Fill a scanline between points x1 and x2 inclusive. x1 < x2.
*/
void
im__draw_scanline( Draw *draw, int y, int x1, int x2 )
{
VipsPel *mp;
int i;
int len;
g_assert( x1 <= x2 );
if( y < 0 || y >= draw->im->Ysize )
return;
if( x1 < 0 && x2 < 0 )
return;
if( x1 >= draw->im->Xsize && x2 >= draw->im->Xsize )
return;
x1 = IM_CLIP( 0, x1, draw->im->Xsize - 1 );
x2 = IM_CLIP( 0, x2, draw->im->Xsize - 1 );
mp = IM_IMAGE_ADDR( draw->im, x1, y );
len = x2 - x1 + 1;
for( i = 0; i < len; i++ ) {
im__draw_pel( draw, mp );
mp += draw->psize;
}
}
void
im__draw_free( Draw *draw )
{
IM_FREE( draw->ink );
}
Draw *
im__draw_init( Draw *draw, IMAGE *im, VipsPel *ink )
{
if( im_rwcheck( im ) )
return( NULL );
draw->im = im;
draw->ink = NULL;
draw->lsize = IM_IMAGE_SIZEOF_LINE( im );
draw->psize = IM_IMAGE_SIZEOF_PEL( im );
draw->noclip = FALSE;
if( ink ) {
if( !(draw->ink = (VipsPel *) im_malloc( NULL, draw->psize )) )
return( NULL );
memcpy( draw->ink, ink, draw->psize );
}
return( draw );
}