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/* Libart_LGPL - library of basic graphic primitives
* Copyright (C) 1998 Raph Levien
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/* Basic constructors and operations for bezier paths */
#include "config.h"
#include "art_bpath.h"
#include <math.h>
/**
* art_bpath_affine_transform: Affine transform an #ArtBpath.
* @src: The source #ArtBpath.
* @matrix: The affine transform.
*
* Affine transform the bezpath, returning a newly allocated #ArtBpath
* (allocated using art_alloc()).
*
* Result (x', y') = (matrix[0] * x + matrix[2] * y + matrix[4],
* matrix[1] * x + matrix[3] * y + matrix[5])
*
* Return value: the transformed #ArtBpath.
**/
ArtBpath *
art_bpath_affine_transform (const ArtBpath *src, const gdouble matrix[6])
{
gint i;
gint size;
ArtBpath *new;
ArtPathcode code;
gdouble x, y;
for (i = 0; src[i].code != ART_END; i++);
size = i;
new = art_new (ArtBpath, size + 1);
for (i = 0; i < size; i++)
{
code = src[i].code;
new[i].code = code;
if (code == ART_CURVETO)
{
x = src[i].x1;
y = src[i].y1;
new[i].x1 = matrix[0] * x + matrix[2] * y + matrix[4];
new[i].y1 = matrix[1] * x + matrix[3] * y + matrix[5];
x = src[i].x2;
y = src[i].y2;
new[i].x2 = matrix[0] * x + matrix[2] * y + matrix[4];
new[i].y2 = matrix[1] * x + matrix[3] * y + matrix[5];
}
else
{
new[i].x1 = 0;
new[i].y1 = 0;
new[i].x2 = 0;
new[i].y2 = 0;
}
x = src[i].x3;
y = src[i].y3;
new[i].x3 = matrix[0] * x + matrix[2] * y + matrix[4];
new[i].y3 = matrix[1] * x + matrix[3] * y + matrix[5];
}
new[i].code = ART_END;
new[i].x1 = 0;
new[i].y1 = 0;
new[i].x2 = 0;
new[i].y2 = 0;
new[i].x3 = 0;
new[i].y3 = 0;
return new;
}
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