mirror of https://github.com/GNOME/gimp.git
544 lines
15 KiB
C
544 lines
15 KiB
C
/* GIMP - The GNU Image Manipulation Program
|
|
* Copyright (C) 1995-2001 Spencer Kimball, Peter Mattis, and others
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 3 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include <glib-object.h>
|
|
|
|
#include "libgimpmath/gimpmath.h"
|
|
|
|
#include "core-types.h"
|
|
|
|
#include "gimp-transform-utils.h"
|
|
|
|
|
|
void
|
|
gimp_transform_get_rotate_center (gint x,
|
|
gint y,
|
|
gint width,
|
|
gint height,
|
|
gboolean auto_center,
|
|
gdouble *center_x,
|
|
gdouble *center_y)
|
|
{
|
|
g_return_if_fail (center_x != NULL);
|
|
g_return_if_fail (center_y != NULL);
|
|
|
|
if (auto_center)
|
|
{
|
|
*center_x = (gdouble) x + (gdouble) width / 2.0;
|
|
*center_y = (gdouble) y + (gdouble) height / 2.0;
|
|
}
|
|
}
|
|
|
|
void
|
|
gimp_transform_get_flip_axis (gint x,
|
|
gint y,
|
|
gint width,
|
|
gint height,
|
|
GimpOrientationType flip_type,
|
|
gboolean auto_center,
|
|
gdouble *axis)
|
|
{
|
|
g_return_if_fail (axis != NULL);
|
|
|
|
if (auto_center)
|
|
{
|
|
switch (flip_type)
|
|
{
|
|
case GIMP_ORIENTATION_HORIZONTAL:
|
|
*axis = ((gdouble) x + (gdouble) width / 2.0);
|
|
break;
|
|
|
|
case GIMP_ORIENTATION_VERTICAL:
|
|
*axis = ((gdouble) y + (gdouble) height / 2.0);
|
|
break;
|
|
|
|
default:
|
|
g_return_if_reached ();
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_flip (GimpMatrix3 *matrix,
|
|
GimpOrientationType flip_type,
|
|
gdouble axis)
|
|
{
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
switch (flip_type)
|
|
{
|
|
case GIMP_ORIENTATION_HORIZONTAL:
|
|
gimp_matrix3_translate (matrix, - axis, 0.0);
|
|
gimp_matrix3_scale (matrix, -1.0, 1.0);
|
|
gimp_matrix3_translate (matrix, axis, 0.0);
|
|
break;
|
|
|
|
case GIMP_ORIENTATION_VERTICAL:
|
|
gimp_matrix3_translate (matrix, 0.0, - axis);
|
|
gimp_matrix3_scale (matrix, 1.0, -1.0);
|
|
gimp_matrix3_translate (matrix, 0.0, axis);
|
|
break;
|
|
|
|
case GIMP_ORIENTATION_UNKNOWN:
|
|
break;
|
|
}
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_flip_free (GimpMatrix3 *matrix,
|
|
gdouble x1,
|
|
gdouble y1,
|
|
gdouble x2,
|
|
gdouble y2)
|
|
{
|
|
gdouble angle;
|
|
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
angle = atan2 (y2 - y1, x2 - x1);
|
|
|
|
gimp_matrix3_identity (matrix);
|
|
gimp_matrix3_translate (matrix, -x1, -y1);
|
|
gimp_matrix3_rotate (matrix, -angle);
|
|
gimp_matrix3_scale (matrix, 1.0, -1.0);
|
|
gimp_matrix3_rotate (matrix, angle);
|
|
gimp_matrix3_translate (matrix, x1, y1);
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_rotate (GimpMatrix3 *matrix,
|
|
GimpRotationType rotate_type,
|
|
gdouble center_x,
|
|
gdouble center_y)
|
|
{
|
|
gdouble angle = 0;
|
|
|
|
switch (rotate_type)
|
|
{
|
|
case GIMP_ROTATE_90:
|
|
angle = G_PI_2;
|
|
break;
|
|
case GIMP_ROTATE_180:
|
|
angle = G_PI;
|
|
break;
|
|
case GIMP_ROTATE_270:
|
|
angle = - G_PI_2;
|
|
break;
|
|
}
|
|
|
|
gimp_transform_matrix_rotate_center (matrix, center_x, center_y, angle);
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_rotate_rect (GimpMatrix3 *matrix,
|
|
gint x,
|
|
gint y,
|
|
gint width,
|
|
gint height,
|
|
gdouble angle)
|
|
{
|
|
gdouble center_x;
|
|
gdouble center_y;
|
|
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
center_x = (gdouble) x + (gdouble) width / 2.0;
|
|
center_y = (gdouble) y + (gdouble) height / 2.0;
|
|
|
|
gimp_matrix3_translate (matrix, -center_x, -center_y);
|
|
gimp_matrix3_rotate (matrix, angle);
|
|
gimp_matrix3_translate (matrix, +center_x, +center_y);
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_rotate_center (GimpMatrix3 *matrix,
|
|
gdouble center_x,
|
|
gdouble center_y,
|
|
gdouble angle)
|
|
{
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
gimp_matrix3_translate (matrix, -center_x, -center_y);
|
|
gimp_matrix3_rotate (matrix, angle);
|
|
gimp_matrix3_translate (matrix, +center_x, +center_y);
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_scale (GimpMatrix3 *matrix,
|
|
gint x,
|
|
gint y,
|
|
gint width,
|
|
gint height,
|
|
gdouble t_x,
|
|
gdouble t_y,
|
|
gdouble t_width,
|
|
gdouble t_height)
|
|
{
|
|
gdouble scale_x = 1.0;
|
|
gdouble scale_y = 1.0;
|
|
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
if (width > 0)
|
|
scale_x = t_width / (gdouble) width;
|
|
|
|
if (height > 0)
|
|
scale_y = t_height / (gdouble) height;
|
|
|
|
gimp_matrix3_identity (matrix);
|
|
gimp_matrix3_translate (matrix, -x, -y);
|
|
gimp_matrix3_scale (matrix, scale_x, scale_y);
|
|
gimp_matrix3_translate (matrix, t_x, t_y);
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_shear (GimpMatrix3 *matrix,
|
|
gint x,
|
|
gint y,
|
|
gint width,
|
|
gint height,
|
|
GimpOrientationType orientation,
|
|
gdouble amount)
|
|
{
|
|
gdouble center_x;
|
|
gdouble center_y;
|
|
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
if (width == 0)
|
|
width = 1;
|
|
|
|
if (height == 0)
|
|
height = 1;
|
|
|
|
center_x = (gdouble) x + (gdouble) width / 2.0;
|
|
center_y = (gdouble) y + (gdouble) height / 2.0;
|
|
|
|
gimp_matrix3_identity (matrix);
|
|
gimp_matrix3_translate (matrix, -center_x, -center_y);
|
|
|
|
if (orientation == GIMP_ORIENTATION_HORIZONTAL)
|
|
gimp_matrix3_xshear (matrix, amount / height);
|
|
else
|
|
gimp_matrix3_yshear (matrix, amount / width);
|
|
|
|
gimp_matrix3_translate (matrix, +center_x, +center_y);
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_perspective (GimpMatrix3 *matrix,
|
|
gint x,
|
|
gint y,
|
|
gint width,
|
|
gint height,
|
|
gdouble t_x1,
|
|
gdouble t_y1,
|
|
gdouble t_x2,
|
|
gdouble t_y2,
|
|
gdouble t_x3,
|
|
gdouble t_y3,
|
|
gdouble t_x4,
|
|
gdouble t_y4)
|
|
{
|
|
GimpMatrix3 trafo;
|
|
gdouble scalex;
|
|
gdouble scaley;
|
|
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
scalex = scaley = 1.0;
|
|
|
|
if (width > 0)
|
|
scalex = 1.0 / (gdouble) width;
|
|
|
|
if (height > 0)
|
|
scaley = 1.0 / (gdouble) height;
|
|
|
|
gimp_matrix3_translate (matrix, -x, -y);
|
|
gimp_matrix3_scale (matrix, scalex, scaley);
|
|
|
|
/* Determine the perspective transform that maps from
|
|
* the unit cube to the transformed coordinates
|
|
*/
|
|
{
|
|
gdouble dx1, dx2, dx3, dy1, dy2, dy3;
|
|
|
|
dx1 = t_x2 - t_x4;
|
|
dx2 = t_x3 - t_x4;
|
|
dx3 = t_x1 - t_x2 + t_x4 - t_x3;
|
|
|
|
dy1 = t_y2 - t_y4;
|
|
dy2 = t_y3 - t_y4;
|
|
dy3 = t_y1 - t_y2 + t_y4 - t_y3;
|
|
|
|
/* Is the mapping affine? */
|
|
if ((dx3 == 0.0) && (dy3 == 0.0))
|
|
{
|
|
trafo.coeff[0][0] = t_x2 - t_x1;
|
|
trafo.coeff[0][1] = t_x4 - t_x2;
|
|
trafo.coeff[0][2] = t_x1;
|
|
trafo.coeff[1][0] = t_y2 - t_y1;
|
|
trafo.coeff[1][1] = t_y4 - t_y2;
|
|
trafo.coeff[1][2] = t_y1;
|
|
trafo.coeff[2][0] = 0.0;
|
|
trafo.coeff[2][1] = 0.0;
|
|
}
|
|
else
|
|
{
|
|
gdouble det1, det2;
|
|
|
|
det1 = dx3 * dy2 - dy3 * dx2;
|
|
det2 = dx1 * dy2 - dy1 * dx2;
|
|
|
|
trafo.coeff[2][0] = (det2 == 0.0) ? 1.0 : det1 / det2;
|
|
|
|
det1 = dx1 * dy3 - dy1 * dx3;
|
|
|
|
trafo.coeff[2][1] = (det2 == 0.0) ? 1.0 : det1 / det2;
|
|
|
|
trafo.coeff[0][0] = t_x2 - t_x1 + trafo.coeff[2][0] * t_x2;
|
|
trafo.coeff[0][1] = t_x3 - t_x1 + trafo.coeff[2][1] * t_x3;
|
|
trafo.coeff[0][2] = t_x1;
|
|
|
|
trafo.coeff[1][0] = t_y2 - t_y1 + trafo.coeff[2][0] * t_y2;
|
|
trafo.coeff[1][1] = t_y3 - t_y1 + trafo.coeff[2][1] * t_y3;
|
|
trafo.coeff[1][2] = t_y1;
|
|
}
|
|
|
|
trafo.coeff[2][2] = 1.0;
|
|
}
|
|
|
|
gimp_matrix3_mult (&trafo, matrix);
|
|
}
|
|
|
|
/* modified gaussian algorithm
|
|
* solves a system of linear equations
|
|
*
|
|
* Example:
|
|
* 1x + 2y + 4z = 25
|
|
* 2x + 1y = 4
|
|
* 3x + 5y + 2z = 23
|
|
* Solution: x=1, y=2, z=5
|
|
*
|
|
* Input:
|
|
* matrix = { 1,2,4,25,2,1,0,4,3,5,2,23 }
|
|
* s = 3 (Number of variables)
|
|
* Output:
|
|
* return value == TRUE (TRUE, if there is a single unique solution)
|
|
* solution == { 1,2,5 } (if the return value is FALSE, the content
|
|
* of solution is of no use)
|
|
*/
|
|
static gboolean
|
|
mod_gauss (gdouble matrix[],
|
|
gdouble solution[],
|
|
gint s)
|
|
{
|
|
gint p[s]; /* row permutation */
|
|
gint i, j, r, temp;
|
|
gdouble q;
|
|
gint t = s + 1;
|
|
|
|
for (i = 0; i < s; i++)
|
|
{
|
|
p[i] = i;
|
|
}
|
|
|
|
for (r = 0; r < s; r++)
|
|
{
|
|
/* make sure that (r,r) is not 0 */
|
|
if (matrix[p[r] * t + r] == 0.0)
|
|
{
|
|
/* we need to permutate rows */
|
|
for (i = r + 1; i <= s; i++)
|
|
{
|
|
if (i == s)
|
|
{
|
|
/* if this happens, the linear system has zero or
|
|
* more than one solutions.
|
|
*/
|
|
return FALSE;
|
|
}
|
|
|
|
if (matrix[p[i] * t + r] != 0.0)
|
|
break;
|
|
}
|
|
|
|
temp = p[r];
|
|
p[r] = p[i];
|
|
p[i] = temp;
|
|
}
|
|
|
|
/* make (r,r) == 1 */
|
|
q = 1.0 / matrix[p[r] * t + r];
|
|
matrix[p[r] * t + r] = 1.0;
|
|
|
|
for (j = r + 1; j < t; j++)
|
|
{
|
|
matrix[p[r] * t + j] *= q;
|
|
}
|
|
|
|
/* make that all entries in column r are 0 (except (r,r)) */
|
|
for (i = 0; i < s; i++)
|
|
{
|
|
if (i == r)
|
|
continue;
|
|
|
|
for (j = r + 1; j < t ; j++)
|
|
{
|
|
matrix[p[i] * t + j] -= matrix[p[r] * t + j] * matrix[p[i] * t + r];
|
|
}
|
|
|
|
/* we don't need to execute the following line
|
|
* since we won't access this element again:
|
|
*
|
|
* matrix[p[i] * t + r] = 0.0;
|
|
*/
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < s; i++)
|
|
{
|
|
solution[i] = matrix[p[i] * t + s];
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
void
|
|
gimp_transform_matrix_handles (GimpMatrix3 *matrix,
|
|
gdouble x1,
|
|
gdouble y1,
|
|
gdouble x2,
|
|
gdouble y2,
|
|
gdouble x3,
|
|
gdouble y3,
|
|
gdouble x4,
|
|
gdouble y4,
|
|
gdouble t_x1,
|
|
gdouble t_y1,
|
|
gdouble t_x2,
|
|
gdouble t_y2,
|
|
gdouble t_x3,
|
|
gdouble t_y3,
|
|
gdouble t_x4,
|
|
gdouble t_y4)
|
|
{
|
|
GimpMatrix3 trafo;
|
|
gdouble opos_x[4];
|
|
gdouble opos_y[4];
|
|
gdouble pos_x[4];
|
|
gdouble pos_y[4];
|
|
gdouble coeff[8 * 9];
|
|
gdouble sol[8];
|
|
gint i;
|
|
|
|
g_return_if_fail (matrix != NULL);
|
|
|
|
opos_x[0] = x1;
|
|
opos_y[0] = y1;
|
|
opos_x[1] = x2;
|
|
opos_y[1] = y2;
|
|
opos_x[2] = x3;
|
|
opos_y[2] = y3;
|
|
opos_x[3] = x4;
|
|
opos_y[3] = y4;
|
|
|
|
pos_x[0] = t_x1;
|
|
pos_y[0] = t_y1;
|
|
pos_x[1] = t_x2;
|
|
pos_y[1] = t_y2;
|
|
pos_x[2] = t_x3;
|
|
pos_y[2] = t_y3;
|
|
pos_x[3] = t_x4;
|
|
pos_y[3] = t_y4;
|
|
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
coeff[i * 9 + 0] = opos_x[i];
|
|
coeff[i * 9 + 1] = opos_y[i];
|
|
coeff[i * 9 + 2] = 1;
|
|
coeff[i * 9 + 3] = 0;
|
|
coeff[i * 9 + 4] = 0;
|
|
coeff[i * 9 + 5] = 0;
|
|
coeff[i * 9 + 6] = -opos_x[i] * pos_x[i];
|
|
coeff[i * 9 + 7] = -opos_y[i] * pos_x[i];
|
|
coeff[i * 9 + 8] = pos_x[i];
|
|
|
|
coeff[(i + 4) * 9 + 0] = 0;
|
|
coeff[(i + 4) * 9 + 1] = 0;
|
|
coeff[(i + 4) * 9 + 2] = 0;
|
|
coeff[(i + 4) * 9 + 3] = opos_x[i];
|
|
coeff[(i + 4) * 9 + 4] = opos_y[i];
|
|
coeff[(i + 4) * 9 + 5] = 1;
|
|
coeff[(i + 4) * 9 + 6] = -opos_x[i] * pos_y[i];
|
|
coeff[(i + 4) * 9 + 7] = -opos_y[i] * pos_y[i];
|
|
coeff[(i + 4) * 9 + 8] = pos_y[i];
|
|
}
|
|
|
|
if (mod_gauss (coeff, sol, 8))
|
|
{
|
|
trafo.coeff[0][0] = sol[0];
|
|
trafo.coeff[0][1] = sol[1];
|
|
trafo.coeff[0][2] = sol[2];
|
|
trafo.coeff[1][0] = sol[3];
|
|
trafo.coeff[1][1] = sol[4];
|
|
trafo.coeff[1][2] = sol[5];
|
|
trafo.coeff[2][0] = sol[6];
|
|
trafo.coeff[2][1] = sol[7];
|
|
trafo.coeff[2][2] = 1;
|
|
}
|
|
else
|
|
{
|
|
/* this should not happen reset the matrix so the user sees that
|
|
* something went wrong
|
|
*/
|
|
gimp_matrix3_identity (&trafo);
|
|
}
|
|
|
|
gimp_matrix3_mult (&trafo, matrix);
|
|
}
|
|
|
|
gboolean
|
|
gimp_transform_polygon_is_convex (gdouble x1,
|
|
gdouble y1,
|
|
gdouble x2,
|
|
gdouble y2,
|
|
gdouble x3,
|
|
gdouble y3,
|
|
gdouble x4,
|
|
gdouble y4)
|
|
{
|
|
gdouble z1, z2, z3, z4;
|
|
|
|
/* We test if the transformed polygon is convex. if z1 and z2 have
|
|
* the same sign as well as z3 and z4 the polygon is convex.
|
|
*/
|
|
z1 = ((x2 - x1) * (y4 - y1) -
|
|
(x4 - x1) * (y2 - y1));
|
|
z2 = ((x4 - x1) * (y3 - y1) -
|
|
(x3 - x1) * (y4 - y1));
|
|
z3 = ((x4 - x2) * (y3 - y2) -
|
|
(x3 - x2) * (y4 - y2));
|
|
z4 = ((x3 - x2) * (y1 - y2) -
|
|
(x1 - x2) * (y3 - y2));
|
|
|
|
return (z1 * z2 > 0) && (z3 * z4 > 0);
|
|
}
|