68 lines
2.1 KiB
C
68 lines
2.1 KiB
C
/* Affine transforms.
|
|
*/
|
|
|
|
/*
|
|
|
|
Copyright (C) 1991-2003 The National Gallery
|
|
|
|
This program 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
|
|
|
|
*/
|
|
|
|
/* Params for an affine transformation.
|
|
*/
|
|
typedef struct {
|
|
/* Area of input we can use. This can be smaller than the real input
|
|
* image: we expand the input to add extra pixels for interpolation.
|
|
*/
|
|
Rect iarea;
|
|
|
|
/* The area of the output we've been asked to generate. left/top can
|
|
* be negative.
|
|
*/
|
|
Rect oarea;
|
|
|
|
/* The transform.
|
|
*/
|
|
double a, b, c, d;
|
|
double dx, dy;
|
|
|
|
double ia, ib, ic, id; /* Inverse of matrix abcd */
|
|
} Transformation;
|
|
|
|
void im__transform_init( Transformation *trn );
|
|
int im__transform_calc_inverse( Transformation *trn );
|
|
int im__transform_isidentity( const Transformation *trn );
|
|
int im__transform_add( const Transformation *in1, const Transformation *in2,
|
|
Transformation *out );
|
|
void im__transform_print( const Transformation *trn );
|
|
|
|
void im__transform_forward_point( const Transformation *trn,
|
|
const double x, const double y, double *ox, double *oy );
|
|
void im__transform_invert_point( const Transformation *trn,
|
|
const double x, const double y, double *ox, double *oy );
|
|
void im__transform_forward_rect( const Transformation *trn,
|
|
const Rect *in, Rect *out );
|
|
void im__transform_invert_rect( const Transformation *trn,
|
|
const Rect *in, Rect *out );
|
|
|
|
void im__transform_set_area( Transformation * );
|