Files
gtk/testsuite/gsk/curve-special-cases.c
Matthias Clasen e7590e78ac Add a test for tangents of degenerate curves
The stroker relies on these to work.
2023-07-06 13:02:19 -04:00

323 lines
9.8 KiB
C

/*
* Copyright © 2020 Benjamin Otte
*
* This library 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 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
* Authors: Benjamin Otte <otte@gnome.org>
*/
#include <gtk/gtk.h>
#include "gsk/gskcurveprivate.h"
static gboolean
measure_segment (const graphene_point_t *from,
const graphene_point_t *to,
float from_t,
float to_t,
GskCurveLineReason reason,
gpointer data)
{
float *length = data;
*length += graphene_point_distance (from, to, NULL, NULL);
return TRUE;
}
static float
measure_length (const GskCurve *curve)
{
float result = 0;
gsk_curve_decompose (curve, 0.5, measure_segment, &result);
return result;
}
/* This is a pretty nasty conic that makes it obvious that split()
* does not respect the progress values, so split() twice with
* scaled factor won't work.
*/
static void
test_conic_segment (void)
{
GskCurve c, s, e, m;
graphene_point_t pts[4] = {
GRAPHENE_POINT_INIT (-1856.131591796875, 46.217609405517578125),
GRAPHENE_POINT_INIT (-1555.9866943359375, 966.0810546875),
GRAPHENE_POINT_INIT (98.94945526123046875, 0),
GRAPHENE_POINT_INIT (-1471.33154296875, 526.701171875)
};
float start = 0.02222645096480846405029296875;
float end = 0.982032716274261474609375;
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CONIC, pts));
gsk_curve_split (&c, start, &s, NULL);
gsk_curve_segment (&c, start, end, &m);
gsk_curve_split (&c, end, NULL, &e);
g_assert_cmpfloat_with_epsilon (measure_length (&c), measure_length (&s) + measure_length (&m) + measure_length (&e), 0.03125);
}
static void
test_curve_tangents (void)
{
GskCurve c;
graphene_point_t p[4];
graphene_vec2_t t;
graphene_point_init (&p[0], 0, 0);
graphene_point_init (&p[1], 100, 0);
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_LINE, p));
gsk_curve_get_start_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
gsk_curve_get_end_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
graphene_point_init (&p[0], 0, 0);
graphene_point_init (&p[1], 0, 100);
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_LINE, p));
gsk_curve_get_start_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_y_axis (), 0.0001));
gsk_curve_get_end_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_y_axis (), 0.0001));
graphene_point_init (&p[0], 0, 0);
graphene_point_init (&p[1], 100, 0);
p[2] = GRAPHENE_POINT_INIT (g_test_rand_double_range (0, 20), 0);
graphene_point_init (&p[3], 100, 100);
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CONIC, p));
gsk_curve_get_start_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
gsk_curve_get_end_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_y_axis (), 0.0001));
graphene_point_init (&p[0], 0, 0);
graphene_point_init (&p[1], 50, 0);
graphene_point_init (&p[2], 100, 50);
graphene_point_init (&p[3], 100, 100);
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CUBIC, p));
gsk_curve_get_start_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
gsk_curve_get_end_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_y_axis (), 0.0001));
}
static void
test_curve_degenerate_tangents (void)
{
GskCurve c;
graphene_point_t p[4];
graphene_vec2_t t;
graphene_point_init (&p[0], 0, 0);
graphene_point_init (&p[1], 0, 0);
graphene_point_init (&p[2], 100, 0);
graphene_point_init (&p[3], 100, 0);
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CUBIC, p));
gsk_curve_get_start_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
gsk_curve_get_end_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
graphene_point_init (&p[0], 0, 0);
graphene_point_init (&p[1], 50, 0);
graphene_point_init (&p[2], 50, 0);
graphene_point_init (&p[3], 100, 0);
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CUBIC, p));
gsk_curve_get_start_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
gsk_curve_get_end_tangent (&c, &t);
g_assert_true (graphene_vec2_near (&t, graphene_vec2_x_axis (), 0.0001));
}
static gboolean
near_one_point (const graphene_point_t *p,
const graphene_point_t *q,
int n,
float epsilon)
{
for (int i = 0; i < n; i++)
{
if (graphene_point_near (p, &q[i], epsilon))
return TRUE;
}
return FALSE;
}
static gboolean
pathop_cb (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer user_data)
{
GskCurve *curve = user_data;
g_assert (op != GSK_PATH_CLOSE);
if (op == GSK_PATH_MOVE)
return TRUE;
gsk_curve_init_foreach (curve, op, pts, n_pts, weight);
return FALSE;
}
static void
parse_curve (GskCurve *c,
const char *str)
{
GskPath *path = gsk_path_parse (str);
gsk_path_foreach (path, -1, pathop_cb, c);
gsk_path_unref (path);
}
static void
test_curve_intersections (void)
{
struct {
const char *c1;
const char *c2;
int n;
graphene_point_t p[9];
} tests[] = {
{ "M 0 100 L 100 100",
"M 0 110 L 100 110",
0, { { 0, 0 }, },
},
{ "M 0 100 L 100 100",
"M 110 100 L 210 100",
0, { { 0, 0 }, },
},
{ "M 0 100 L 100 100",
"M 0 100 L -100 100",
1, { { 0, 100 }, },
},
{ "M 0 100 L 100 100",
"M 20 100 L 80 100",
2, { { 20, 100 }, { 80, 100 }, },
},
{ "M 0 100 L 100 100",
"M 150 100 L 50 100",
2, { { 100, 100 }, { 50, 100 }, },
},
{ "M 888 482 C 999.333313 508.666687 1080.83325 544.333313 1132.5 589",
"M 886 680 L 642 618",
0, { { 0, 0 }, },
},
{ "M 1119.5 772 C 1039.16675 850.666687 925.333313 890 778 890",
"M 1052 1430 734 762",
1, { { 794.851257, 889.825439 }, },
},
{ "M 844.085 271.845 Q 985.723 94.0499 836.718 817.477",
"M 790.206 34.4028 L 965.236 893.041",
1,
{ { 890.685, 527.323 }, }
},
{ "M 521.412 466.917 Q 838.809 472.131 51.3819 192.985",
"M 854.519 682.333 Q 154.655 -50.3073 260.046 627.56",
3, { { 611.932129, 450.019135 }, { 518.727844, 377.701019 }, { 343.737976, 301.792297 } }
},
{ "M 521.412 466.917 Q 838.809 472.131 51.3819 192.985",
"M 854.519 682.333 O 154.655 -50.3073 260.046 627.56 1",
3, { { 611.932129, 450.019135 }, { 518.727844, 377.701019 }, { 343.737976, 301.792297 } }
},
{ "M 521.412 466.917 Q 838.809 472.131 51.3819 192.985",
"M 854.519 682.333 O 154.655 50.3073 260.046 627.56 1.53362",
3, { { 597.725, 460.362 }, { 426.752, 335.879 }, { 310.528, 288.720 }, },
},
};
for (unsigned int i = 0; i < G_N_ELEMENTS (tests); i++)
{
GskCurve c1, c2;
float t1[9], t2[9];
graphene_point_t p[9];
int n;
parse_curve (&c1, tests[i].c1);
parse_curve (&c2, tests[i].c2);
n = gsk_curve_intersect (&c1, &c2, t1, t2, p, 9);
if (g_test_verbose ())
g_print ("expected %d intersections, got %d\n", tests[i].n, n);
if (c1.op == GSK_PATH_CONIC || c2.op == GSK_PATH_CONIC)
{
/* Our conic intersection code can produce duplicate intersections */
for (unsigned int j = 0; j < tests[i].n; j++)
{
if (g_test_verbose ())
g_print ("looking for %f %f\n", tests[i].p[j].x, tests[i].p[j].y);
g_assert_true (near_one_point (&tests[i].p[j], p, n, 0.01));
if (g_test_verbose ())
g_print ("found expected intersection %d\n", j);
}
for (unsigned int j = 0; j < n; j++)
{
if (g_test_verbose ())
g_print ("looking for %f %f\n", p[j].x, p[j].y);
g_assert_true (near_one_point (&p[j], tests[i].p, tests[i].n, 0.01));
if (g_test_verbose ())
g_print ("intersection %d is expected\n", j);
}
}
else
{
g_assert_true (n == tests[i].n);
for (unsigned int j = 0; j < n; j++)
{
if (g_test_verbose ())
g_print ("expected %f %f got %f %f\n",
tests[i].p[j].x, tests[i].p[j].y,
p[j].x, p[j].y);
g_assert_true (graphene_point_near (&p[j], &tests[i].p[j], 0.001));
if (g_test_verbose ())
g_test_message ("intersection %d OK", j);
}
}
if (g_test_verbose ())
g_test_message ("test %d OK", i);
}
}
int
main (int argc,
char *argv[])
{
gtk_test_init (&argc, &argv, NULL);
g_test_add_func ("/curve/special/conic-segment", test_conic_segment);
g_test_add_func ("/curve/special/tangents", test_curve_tangents);
g_test_add_func ("/curve/special/degenerate-tangents", test_curve_degenerate_tangents);
g_test_add_func ("/curve/special/intersections", test_curve_intersections);
return g_test_run ();
}