app: move the handle transform matrix calculation to gimp-transform-utils.[ch]

This commit is contained in:
Michael Natterer 2017-06-17 10:03:24 +02:00
parent 430c31b798
commit 6cd91f1fde
3 changed files with 223 additions and 154 deletions

View File

@ -328,6 +328,193 @@ gimp_transform_matrix_perspective (GimpMatrix3 *matrix,
gimp_matrix3_mult (&trafo, matrix); 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 gboolean
gimp_transform_polygon_is_convex (gdouble x1, gimp_transform_polygon_is_convex (gdouble x1,
gdouble y1, gdouble y1,

View File

@ -85,6 +85,23 @@ void gimp_transform_matrix_perspective (GimpMatrix3 *matrix,
gdouble t_y3, gdouble t_y3,
gdouble t_x4, gdouble t_x4,
gdouble t_y4); gdouble t_y4);
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);
gboolean gimp_transform_polygon_is_convex (gdouble x1, gboolean gimp_transform_polygon_is_convex (gdouble x1,
gdouble y1, gdouble y1,

View File

@ -30,6 +30,7 @@
#include "config/gimpguiconfig.h" /* playground */ #include "config/gimpguiconfig.h" /* playground */
#include "core/gimp.h" /* playground */ #include "core/gimp.h" /* playground */
#include "core/gimp-transform-utils.h"
#include "widgets/gimphelp-ids.h" #include "widgets/gimphelp-ids.h"
#include "widgets/gimpwidgets-utils.h" #include "widgets/gimpwidgets-utils.h"
@ -136,9 +137,6 @@ static inline gdouble calc_lineintersect_ratio (gdouble p1x,
gdouble q1y, gdouble q1y,
gdouble q2x, gdouble q2x,
gdouble q2y); gdouble q2y);
static gboolean mod_gauss (gdouble matrix[],
gdouble solution[],
gint s);
G_DEFINE_TYPE (GimpHandleTransformTool, gimp_handle_transform_tool, G_DEFINE_TYPE (GimpHandleTransformTool, gimp_handle_transform_tool,
@ -609,66 +607,27 @@ gimp_handle_transform_tool_recalc_matrix (GimpTransformTool *tr_tool,
GimpToolWidget *widget) GimpToolWidget *widget)
{ {
GimpHandleTransformTool *ht_tool = GIMP_HANDLE_TRANSFORM_TOOL (tr_tool); GimpHandleTransformTool *ht_tool = GIMP_HANDLE_TRANSFORM_TOOL (tr_tool);
gdouble coeff[8 * 9];
gdouble sol[8];
gdouble opos_x[4];
gdouble opos_y[4];
gdouble pos_x[4];
gdouble pos_y[4];
gint i;
if (ht_tool->matrix_recalculation) if (ht_tool->matrix_recalculation)
{ {
for (i = 0; i < 4; i++) gimp_matrix3_identity (&tr_tool->transform);
{ gimp_transform_matrix_handles (&tr_tool->transform,
pos_x[i] = tr_tool->trans_info[X0 + i * 2]; tr_tool->trans_info[OX0],
pos_y[i] = tr_tool->trans_info[Y0 + i * 2]; tr_tool->trans_info[OY0],
opos_x[i] = tr_tool->trans_info[OX0 + i * 2]; tr_tool->trans_info[OX1],
opos_y[i] = tr_tool->trans_info[OY0 + i * 2]; tr_tool->trans_info[OY1],
} tr_tool->trans_info[OX2],
tr_tool->trans_info[OY2],
for (i = 0; i < 4; i++) tr_tool->trans_info[OX3],
{ tr_tool->trans_info[OY3],
coeff[i * 9 + 0] = opos_x[i]; tr_tool->trans_info[X0],
coeff[i * 9 + 1] = opos_y[i]; tr_tool->trans_info[Y0],
coeff[i * 9 + 2] = 1; tr_tool->trans_info[X1],
coeff[i * 9 + 3] = 0; tr_tool->trans_info[Y1],
coeff[i * 9 + 4] = 0; tr_tool->trans_info[X2],
coeff[i * 9 + 5] = 0; tr_tool->trans_info[Y2],
coeff[i * 9 + 6] = -opos_x[i] * pos_x[i]; tr_tool->trans_info[X3],
coeff[i * 9 + 7] = -opos_y[i] * pos_x[i]; tr_tool->trans_info[Y3]);
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))
{
tr_tool->transform.coeff[0][0] = sol[0];
tr_tool->transform.coeff[0][1] = sol[1];
tr_tool->transform.coeff[0][2] = sol[2];
tr_tool->transform.coeff[1][0] = sol[3];
tr_tool->transform.coeff[1][1] = sol[4];
tr_tool->transform.coeff[1][2] = sol[5];
tr_tool->transform.coeff[2][0] = sol[6];
tr_tool->transform.coeff[2][1] = sol[7];
tr_tool->transform.coeff[2][2] = 1;
}
else
{
/* this should not happen reset the matrix so the user sees
* that something went wrong
*/
gimp_matrix3_identity (&tr_tool->transform);
}
} }
} }
@ -928,97 +887,3 @@ calc_lineintersect_ratio (gdouble p1x, gdouble p1y,
return u / (u - 1); return u / (u - 1);
} }
/* 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;
}